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AMATEUR 


DECEMBER  1976 
SI  .50 


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4 

Never  Say  Die 

6 

Be  My  Guest 

12 

Looking  West 

14 

Contests 

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Oscar  Orbits 

16 

Letters 

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New  Products 

34 

Ham  Help 

70 

I/O  Editorial 

74 

I/O  Report 

173 

Social  Events 

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Hamburglar 

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FCC 

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Propagation 

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See  the  World  and 

Get  Paid!  -  part  If 

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162  Watch  DX  with  a  Spectrum  Analyzer- 

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166  DXing  with  a  Weather  Map  -a  new  6m 

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COVER:   The  Motorola  6800. 

73  Magazine  is  published  monthly 
by  73,  Inc.,  Peterborough  NH 
03458.  Subscription  rates  in  the 
U.S.  and  Canada  are  SW  for  one 
year  and  $20  for  three  years. 
Outside  the  U.S.  and  Canada,  add 
$2.  Second  class  postage  paid  at 
Peterborough  NH  03458  and  at 
additional  mailing  offices,  Phone: 
603-924-3873.  Microfilm  edition 
—  University  Microfilms,  Ann 
Arbor  Ml  48106,  Tapes  -  Science 
for  the  Blind,  332  Rock  Hilt  ftd, 
Bala  Cynwyd  PA  19904.  Entire 
contents  copyright  t97&  by  73, 
Inc.  INCLUDE  OLD  ADDRESS 
AND  ZIP  CODE  WITH 
ADDRESS  CHANGE  NOTIFICA- 
TION. 


STAFF 


EDlTOfi/HJBLISHER 
Wayne  Gr&sn  W2NS0/1 

GENERAL  MANAGER 

Biff  Itfahoney 

MAWAGING  EDITOR 
JoPm  C.  Burnett 

ASSISTANT  EDITOR 

Susan  G,  Philtjrick. 

I/O  EDITOR 

John  Cr^g 

ASSOCIATE  EDITORS 

Rl>th  BruwnWILUT 
Warren  Ell vWAtGUD/1 
flieh  Faro:  WB2QYV71 

PRODUCTION  MANAGER 
Lynn  PgrnzierarFraser 

ART  DEPARTMENT 

Rabin  Macrae 
Virginia  Mammone 

Micbadl    Murphy 

Bob  Sawyer 
Hoftl  R.  Self 

PRINTING 

Brent  Lawier 
Michael-  Potter 

PHOTOGRAPHY 

Gill  Hey(i4jJnh 

TYPESETTING 

Barbara  J.  Latti 
Sandy  White 

COMPTROLLER 

Knud  E,   M.  Kciler  KV4GG-/1 

CIRCULATION 

Dnnjthv  Gibson 
Barbara  Block 
Nancy  Cbandler 
Susan  Chandler 
Fran  Dillon 
Florence  Goldman 

LDiS  i    -  !•:!  -I 
Marge  Nielsen 
Peggy  Sysyrv 
Thuresa  Tausseint 
Jtidv  Waterman 

MARKETING 

Sherry  Smythe 
Cher  Dean 
Lisa  He  ate  y 
Karen  McDonough 
Mary  M^Dnnough 

INVENTORY  CONTROL 

M9nj*ie|l  Raymond 
Gary  SI  am  in 
fli  chard  Viiono 

PLANT  MAINTENANCE 
Bill  Barry 
Lnrrame  Pickering 

ASSOCIATES 
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i    H.  Sarrajtt  WBQILX 
Schley  Co*.  WB9LHO 
Tom  DiBiase  WB8KZP 
Tarry  Fox  WB4JF1 
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Bill  Pasternak  WA6ITF 
John  ScHi/ltJ  W2EEY/K3EZ 
Waller  Scott  K3DIZ 
Peter  Stark  K20AW 

Bill  Turner  WAGABi 

COMPUTER  ENGINEERING 

James  Muartlari 
Daud  E    Wilensky 

DRAFTING 

Bill  Morello 

Lynn  Malq 

T    W.  Graham.  Jr.  WBFKW 

ADVERTISING 

BIN  Edward  WBBBECvl 
Nanicy  Clu  rf  WAiyVSu 


EDITORIAL  BY  WAYNE  GREEN 


73  SUFFERING? 

Is  73  really  dropping  circulation,  as 
ARRL  recently  reported  in  HR 
Reports?  The  fact  is  that  73's  growth 
this  year  has  been  without  precedent 
.  .  .  and  both  HB  and  QST  know  ft 
They  are  hearing  this  From  readers, 
authors,  dealers  {who  tell  them  that 
73  is  outselling  their  magazines  in  the 
radio  stores},  from  newsstand  whole- 
salers (who  say  the  same  thing)  andf 
worst  of  all,  from  the  advertisers. 

The  growth  has  been  a  pain  . .  .  but 
a  most  bearable  one.  We've  just  had  to 
double  the  capacity  of  our  computer 
system  ,  t.,  and  it  was  supposed  to 
hold  us  for  a  couple  more  years.  We've 
had  to  do  second  printings  of  the 
April,  September  and  possibly 
October  issues  because  incoming  sub- 
scriptions have  been  so  far  beyond  our 
projections  ...  and  that  is  horribly 
expensive.  The  staff  has  gone  from  30 
last  year  to  45  this  year  to  handle 
subscriptions,  mailing  lists,  promo- 
tions, artwork,  writing,  editing, 
printing  .  ,  ,  etc. 

Despite  the  rash  of  I/O  articles  in 
73  this  year,  the  subscriptions  have 
been  growing  faster  than  ever  before 
in  our  history  (hey,  did  you  see  the 
microcomputer  article  in  QST  for 
August!},  The  73  formula  of  lots  of 
articles,  few  contest  results,  few 
activity  reports,  few  PhD  type  of 
technical   articles  and   tell   it   like   it 


really  is  approach,  which  is  more  in 
vogue  after  Watergate,  seems  to  work, 
Few  but  older  hams  seem  to  be 
buying  the  blind  loyalty  bit  these  days 
.  .  .  most  want  to  see  signs  of  respon- 
siveness and  relevancy. 

Let's  add  up  the  pages  of  ads  in  the 
ham  magazines  for  the  last  half  of 
1975  and  the  first  half  of  1976  for  a 
direct  comparison.  Keep  in  mind  that 
ads  in  QST  cost  about  10%  more  than 
those  in  73. 


73 


971  pages 


QST        735  pages 
HR  624  pages 

CQ  306  pages 


Perhaps  the  chart  above  will  put 
things  into  perspective.  It  shows  73 
with  32%  more  ads  than  QST"  (and  a 
lot  fatter  magazine  ,  , ,  without  all  the 
contest  results,  SCM  reports,  and  that 
stuff).  After  over  50  years  as  number 
one,  this  is  a  very  bitter  pill  to 
swallow,  and  it  fs  no  wonder  that 
there  is  some  nervousness  in  Newing- 
ton.  Figures  lie  and  liars  figure,  to 
coin  a  phrase. 

TECHS'LL  PROBABLY 

HATE  ME 

Not  a  few  people  have  petitioned 

the   FCC  to  open  part  or  all  of  ten 

meters  for  Techs.    It  is  a  matter  of 

religious  significance  to  some  Techs. 


t — ~— — 


••••••  • 


^j    |    •      ■      ■■■    ■; 


i 


\ 


Since  hamfests,  conventions  and  computerfests  are  commercial  affairs,  2m  NTs 
should  not  be  used  for  coordination.  Here's  one  of  the  officials  of  PC -76  in  the 
middle  of  a  no -no.  This  sort  of  thing  would  be  okay  using  CBf  hut  not  ham 
radio. 


At  the  present  time  I  am  neither  for 
nor  against  the  idea.  However,  I  would 
like  to  see  someone  come  up  with  a 
good  reasonable  argument  which 
would  convince  me  that  it  was  a  valid 
idea. 

Yes,  I  think  I  know  all  of  the 
arguments  ,  ♦  .  but  I  may  have  missed 
some.  Ten  needs  activity  . .  .  no  ques- 
tion about  it.  But  blessed  if  anyone 
has  come  up  with  any  data  which 
indicates  even  remotely  that  Techs 
will  use  ten  meters  if  we  open  it  tor 
them.  All  that  data  I've  seen  so  far 
points  the  other  way. 

Six  was  the  biggy  a  few  years  back 
.  .  .  right?  You  could  find  about  90% 
of  the  active  Techs  chewing  away  on 
six  ...  maybe  95%,  Then  some  chap 
(prizes  if  you  know  who}  started 
really  pushing  two  meter  FM  and 
repeaters  and  got  things  perking  up 
there.  Instant  flushing  of  six  ... 
which  turned  into  a  ghost  band.  Mow 
95%  of  the  active  Techs  were  on  two 
meters,  with  a  thin  scattering  on  six, 
450  .  .  .  and  even  a  half  dozen  or  so 
on  220  IvlHz. 

From  that,  one  might  be  tempted 
to  suspect  that  Techs  (like  all  other 
classes  of  hams}  tend  to  go  where  the 
action  Is.  OK  ...  so  what  about  ten 
meters?  Well,  with  over  200,000 
licensed  amateurs  with  tickets  which 
do  permit  them  to  operate  on  ten  .  .  . 
and  with  a  mere  handful  doing  same, 
why  on  earth  should  we  expect  Techs 
to  suddenly  reverse  their  practice  of 
ignoring  inactive  bands?  When  you 
have  a  good  explanation  for  that,  let 
me  know  and  you'll  find  a  heavy  hand 
pushing  for  Techs  on  ten, 

tf  Techs  are  so  great  at  helping  keep 
bands  busy,  where  are  they  on  220 
MHz?  Where  are  they  on  six  meters? 
You  know  where  they  are  . .  .  they  are 
on  two  meters.  And  f  don't  want  to 
hear  from  the  tiny  band  of  pioneering 
Techs  who  are  out  there  trying  to 
shovel  coal  up  the  chute  (to  coin  a 
phrase},  fighting  a  tough  battle  to 
keep  soma  thing  going  on  bands  other 
than  two.  Fair  is  fair,  fellows, 

WARC  -  WHAT  YOU  CAM  DO 
Okay,  so  most  of  us  are  worried 
about  what  might  happen  at  the  next 
ITU  conference  in  1979.  Again  there 
is  every  reason  to  worry,  particularly 
if  you  have  any  real  knowledge  of 
where  amateur  radio  stands  with  other 
countries. 

As  I  mentioned  in  my  October 
editorial,  the  only  chance  that  I  see 

Continued  on  page  178 


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300  Channels:  5  KHi  spaced 

Sensitivity:  Better  than  0.4  uV  for  20 

dB  quieting 
Better  lhan  1  uV  for  30 

dB  S/N 

Squelch  Sensitivity    Betier  then 
0.25  uV 

Selectivity:  1  2  KHr  at  -6  dB  dawn 
40  KHz  at  -70  dB  down 

Image  Rejection    Better  than  —70  dB 


VOL-®- SOU 


fKENWOOO 


ftOU     0*F 


TRANSCEIVER 


MHz 


'  i     L 
1     U 


QH  *IR 


+  500 
-600 


MIN 


•A** 


100  kHz 


10  kHz 


MHZ 


MIC 


5*Hl 


- 


TX  OFFSET 
4-aoo 


NE 


A  m     M  low 


POWER 


»ON 


—6 


TP-7400A 


Featuring  Kenwood's  New  and  Unique 
CONTINUOUS  TONE  CODED  SQUELCH  SYSTEM 


4  MHz  BAND  COVERAGE 


25  WATT  OUTPUT 


FULLY  SYNTHESIZED 


UNIQUE  SQUELCH  SYSTEM 
The  TR-7400A  may  be  used  on  your  favorite 
repeater,  no  matter  what  type  of  squelch 
system  is  used-  The  continuous  tone  coded 
squelch  (CTCS)  may  be  used  for  both  trans- 
mit and  receive  or  for  transmit  only.  Tone 
burst  operation  may  also  be  used, 

SYNTHESIZED,  800  CHANNELS 
The  phase-locked  loop  {PLL)  frequency  syn- 
thesizer in  the  TR-74G0A  divides  the  4  MHz 
bandwidth  into  400  channels  at  intervals  of 
10  KHz  The  frequency  may  be  offset  5  KHz 
higher  with  the  push  of  a  button,  thus  pro- 
viding 800  discrete  channels 

REPEATER  OFFSET 

A  convenient  front  panel  switch  offsets  the 
transmit  frequency  of  the  TR-7400A  up  OR 
down  GOO  KHz  for  standard  repeater  opera- 
tion This  offset  circuit  uses  digital  technology 
to  provide  a  highly  stable  offset  frequency 
without  spurious  response   A  dual  color  LED 


indicates  the  direction  of  offset  from  the  dis- 
played receive  frequency. 

OUTSTANDING  RECEIVER  PERFORMANCE 
Large-sized   helical   resonators  with   high   Q 
minimize  undesirable  interference  from  out- 
side the  2-meter  band.  The  large  helical  res- 
onators, 2 -pole  10,7  MHz  monolithic  crystal 


filter,  and  M;rOSFET  front-end  circuitry  com- 
bine to  give  outstanding  receiver  performance, 

TONE  PAD  CAPABILITY 

A  jack  is  provided  to  allow  convenient  con- 
nection of  a  tone  pad  to  the  TR  7400A. 

FINAL  PROTECTION  CIRCUIT 
The  final  transistor  in  the  TR  7400 A  is  pro- 
tected from  antenna  impedance  mismatch. 
Excessive  reflected  power  reduces  the  amount 
of  drive  to  the  final  transistor  rather  than 
turning  off  the  final  stage.  This  practical  fea- 
ture allows  continued  safe  operation  at  a 
reduced  power  level  whether  the  antenna 
system  becomes  opened  or  shorted 


Spurious  Interference    Better  lhan 

-60  dB 
Inter  modulation:  Better  than  66  dB 
Receive  System   Double  conversion 
First  IF:  10-7  MHz 
Second  IF:  455  KHz 

Audio  Output:  More  than  1.5  Watts 

(8  ohm  load) 

RF  Output  Power    25  Wans  (High) 

515  Watts  (Low^ 
adjustable) 

Antenna  Impedance    50  ohms 

Frequency  Deviation    +S  KHz 

Spurious  Response   Belter  than 
-60  dB 

Tone  Pad  Input  impedance   600  ohms 

Tone  Burst  Duration   0  5  to  1  0  sec. 

CTCS  Range:  88  5  Hz  to  156  7'Hz 

Microphone:  Dynamic  with  PTT 
sw>tchr  500  ohms 

Voltage   11.5  to  16.0V  DC  fl 3  8V  DC 
nominal) 

Current  Dram:  Less  than  1 A  in  receive 

{no  tnput  signaO 
Current  Drain:  Less  lhan  BA  in  transmit 

Polarity:  Negative  ground 
Temperature  Range:  —20  to  +50 

degrees  C 
Dimensions.  182  mm  (7-3    161  wide 
270  mm  {10-5/8")  deep. 
74  mm  (2*7/8")  high 

Net  Weight.  Approximately  2.8  kg 
(62  lbs.) 


TRtO-KElMWGOD   COMMUNICATIONS   INC 
116  EAST  ALONDRA/GARDENA,  Q£  90248 


®  KENWOOD 


•  pacesetter  m  amateur  radin 


visiting  views  from  around  the  globe 


Little... 


Every  day  records  are  falling.  Divers 
are  setting  new  underwater  poker 
playing  records.  Jets  are  crossing  the 
Atlantic  at  supersonic  speed,  A  group 
of  Nashua,  New  Hampshire  folks  re- 
cently set  the  world's  record  for 
rocking  chair  rocking.  And  out  in  a 
small  midwestem  town  this  summer,  a 
five  year  old  boy  has  earned  a  Novice 
class  amateur  radio  license.  It  boggles 
the  mind 

Nell  "Rusty"  Rapp  WN9VPG  of 
Vincennes.  Indiana  will  only  start  first 
grade  this  fall,  At  age  four  the  boy's 
reading  ability  was  estimated  to  be  at 
the  fifth  grade  level.  His  Novice  code 
test  features  inch  high  tetters,  and  a 
better  score  (103)  than  his  father. 
Rusty  learned  the  code  in  only  seven 
weeks  and  passed  his  theory  exam  in 
about  half  an  hour.  Already  he's 
bored  with  the  Novice  bands,  and  is 
studying  hard  for  his  General. 


As  near  as  we  can  tell,  the  old 
world's  record  for  youngest  ham  was 
Gary  Lewis  WN7BBJ.  Lewis  was  seven 
when  he  got  his  license,  but  the 
CaUbook  says  he's  no  longer  licensed, 
or  has  another  call,  A  fellow  In  Wash- 
ington now  holds  N7BSJ. 

Rusty  began  on  the  CB  bands,  after 
his  dad,  now  a  Novice,  bought  a  CB 
radio.  Rusty  caught  on  fast,  memor- 
izing handles  and  callsigns  and 
becoming  a  local  legend  on  channel 
13.  He  used  the  handle  "Little 
Shadow." 

At  Christmas  time,  the  elder  Rapp 
dusted  off  a  code  key  and  oscillator 
and  decided  to  get  into  ham  radio. 
Father  and  son  had  been  practicing 
for  several  weeks  when  they  spotted 
an  ad  in  the  local  paper:  The  Old  Post 
Office  Amateur  Radio  Society  was 
offering  Novice  classes,  the  minimum 
age  requirement  being  10. 

The  first  night,  Dei  Rapp  left  his 
son  home,  afraid  of  the  ag&  limit.  But 
there  was  a  ten  year  old  girl  enrolled, 
so  the  next  week  it  was  Ru sty's 
chance.  Three  weeks  later,  father 
passed  the  code  test,  but  Rusty  failed. 
He'd  been  told  not  to  turn  over  his 
paper  ...  but  since  the  boy  wrote  in 
such  big  tetters,  he'd  run  cut  of  paper 
and  couldn't  copy  enough  characters. 

Rusty,    according   to   his   mother, 


\.A.h<T<i    J*.:t    If., 


ttfiY- 


P<~.  f      C/WcAfl. 


c£S&^. 


-  -15" 


Stoi 


IMOp1 


dcvrflJ&LzJrKtidL 


i  r^A  ■ 


*m£M$& 


6 


cried  until  midnight  , ,  ,  and  there 
were  doubts  whether  he  ought  to 
continue.  Two  weeks  later,  the  code 
hurdle  was  eliminated,  thanks  to  the 
watchful  eyes  and  ears  of  Bill  Sage 
K9(HU,  the  club  code  instructor. 

Then  it  was  onto  theory  and  it  was 
tough  going.  Rusty's  mom  decided  to 
come  up  with  a  game,  so  the  boy 
could  memorize  the  questions  and 
answers  "backwards  and  forwards." 
They  put  the  questions  on  one  set  of 
cards  and  the  answers  on  another, 
Father  and  son  then  questioned  each 
other  with  gusto,  using  pennies  and 
then  peanuts  to  reward  correct 
answers. 

The  Rapps  must  have  gone  through 
a  lot  of  peanuts,  because  it  turned  out 
the  FCC  lost  Rusty's  application. 
More  than  three  months  after  the 
code  test,  it  was  finally  time  for 
theory- 
It  must  have  been  quite  a  sight,  a 
five  year  old  boy  poring  over  the 
exam  questions  : .  .  filling  out  the 
computer  answer  Form+  How  many  of 
us  have  been  there,  with  years  of 
schooling  and  hours  of  study,  only  to 
fail  and  have  to  try  another  day4 
Theory  instructor  Howard  Haze I man 
K9SLV  probably  still  doesn't  believe 
it  When  Rusty  passed  his  code  test, 
the  entire  class  signed  his  exam  paper 
.  .  .  because  the  instructor  feared  no 
one  would  believe  a  five  year  old  boy 
could  pass, 

You  can  imagine  the  look  on 
K3DIPs  face  when  he  gave  WN9VPG 
his  first  GSQ  on  15  meters.  It  turned 
out  K3DIF  worked  for  Associated 
Press    in    Washington,    DC.    and    the 


story  of  the  world's  youngest  ham  was 
on  its  way  into  print.  A  half  dozen 
radio  and  newspaper  stories  followed. 
Rusty  even  heard  from  First  Mama 
Betty  Ford,  who  replied  with  a  big 
10-4  and  a  form  fetter  sigied,  "Nice 
modulating  with  you  J"  (The  White 
House    is    apparently    short    of    ham 


Photo  by  Paul  Willis 

radio  form  tetters.) 

One  thing's  sure:  Rusty  Rapp's 
achievement  should  be  an  inspiration 
to  all  of  us,  whether  we  be  Novices 
seeking  General  class  licenses,  CBers 
trying  to  get  into  hamming,  or  Ad- 
vanced licensees  struggling  to  get  the 
code  speed  up  to  20  for  the  Extra- 


There  is  something  to  that  ancient 
saying,  "And  a  little  child  shall  lead 
them  .  .  /'  Meanwhile,  I'm  firing  up 
on  21,120  MHz  this  Sunday  for  the 
Old  Post  Novice  Wet,  at  midnight 
GMT,  hoping  to  reach  that  five  year 
old  Mo  vice  and  taste  a  bit  of  the 
world's  youngest  fiSL 


A  recent  report  to  the  Office  of 
Telecommunications  Policy,  Execu- 
tive Office  of  the  President,  warns  of 
the  potential  for  breakdown  of  the 
federal  regulatory  system  in  the  face 
of  rapidly  developing  telecommunica- 
tions technology.  Prepared  by  Arthur 
D,  Little,  Inc.,  the  report  foresees  the 
headlong  growth  of  Citizens  Band 
radio  resulting  in  new  criminal  tech- 
niques and  the  Postal  Service  threat- 
ened with  obsolescence.  Even  AT&T's 
gaining  a  monopoly  of  all  broadband 
distribution  to  the  home  is  among 
other  possible  impacts  of  technologi- 
cal change, 

Martin  Ernst,  director  of  the  study, 
says  the  report  is  not  a  prediction,  but 
a  warning  of  the  kinds  of  chaos  that 
could  result  if  the  status  quo  is  main- 
tained. "It's  not  a  matter  of  more 
regulations,"  he  stated,  "but  of  how 
telecommunications  should  be  regu 
lated  Much  of  the  technological 
change  we  assessed  is  already  well  on 
its  way*  It  can't  easily  be  turned  back. 
The  regulatory  framework  has  to  be 
rethought  to  deal  with  the  possible 
social  impacts/'  he  explained.  "Over 
regulation  certainly  is  not  the  answer. 
In  fact,  sections  of  our  study  focus  on 
the  dangers  of  too  much  regulation, 
especially  if  it  cannot  in  practice  be 
enforced." 

Commissioned  by  the  Office  of 
Telecommunications    Policy    as    the 


first  step  in  the  process  of  planning 
for  the  impacts  of  telecommunica- 
tions change,  the  report  consists  of 
five  scenarios.  They  develop  possible, 
though  not  necessarily  likely,  chains 
of  events  in  such  fields  as  mail  deliv- 
ery, CB  usage,  broadcast  distribution, 
broadband  communications,  and  edu- 
cation. The  scenarios  were  developed 
to  dramatize  a  broad  range  of  possible 
impacts  on  individuals,  society  as  a 
whole,  and  the  economy. 

Pervasiveness  of  Telecommunications 

The  visible  forms  of  telecommuni- 
cations (telephones,  television,  radio) 
give  few  clues  to  its  pervasiveness,  The 
invisible  nature  of  its  more  critical 
aspects  (electronic  networks,  com- 
munications satellites,  cable  systems, 
and  other  operations  which  make 
these  things  possible)  has  led  to  its 
casual  acceptance,  according  to  the 
report  "Most  users  are  unaware,  for 
example,  of  the  technical,  economic, 
and  political  considerations  that  deter- 
mined specifications  for  equipment 
such  as  television  sets  before  they 
could  be  marketed  or  what  alternative 
performance  possibilities  were  and  are 
available.  Not  only  the  costs  and 
quality  of  equipment,  but  even  per- 
sonal safety  and  national  security  can 
be  determined  by  remote  decisions 
that  are  difficult  for  all  but  the  most 
experienced    and    well    informed    to 


. . .  News 


comprehend  fully/'  the  report  states. 
Similarly,  few  of  the  recipients  of 
electronically  transmitted  Social 
Security  payments,  Dtizeni  Band 
radio  enthusiasts,  or  cable  TV 
customers  are  aware  of  thrj 
mechanisms  involved  and  the  poten- 
tial for  sweeping  change  represented 
therein. 

With  the  possible  exception  of 
transportation,  the  report  points  out 
that  telecom  muni  cat  ions  has  no  rival 
m  the  degree  to  whtch  it  is  a  part  of 


American  life,  Repercussions  of  seem- 
ingly isolated  and  relatively  unim- 
portant decisions  regarding  a  single 
aspect  of  it  can  affect  a  broad  range  of 
human  activities,  For  example,  a  CB 
radio  frequency  band  decision  to  open 
more  channels  would  affect  imports 
and  thus,  among  other  effects,  change 
the  balance  of  payments.  It  also  could 
affect  treaties  with  other  nations, 
notably  Canada. 

The   meteoric  growth   of   Citizens 
Band  radio  already  has  overcrowded 


the  channels  available  to  iL  This  could 
affect  international  relations  because 
the  use  of  present  frequencies  during 
periods  of  high  surtspot  activity(  such 
as  that  anticipated  in  1979,  could 
interfere  with  radio  operations  In 
other  countries  where  amateur  radio  is 
more  rigidly  controlled.  In  that  con- 
text, the  study  notes,  no  other  nation 
has  permitted  access  to  a  Citizens 
Band  because  of  the  many  and  diffi- 
cult problems  such  access  creates. 

Outcome  of  CB  Radio  Boom 

The     study     team     developed     a 
scenario    of    possible    events    arising 


from  the  proliferating  use  of  CB 
radios,  The  team  believes  that  hoards 
of  new  users  and  additional  uses  could 
in  the  not  too  distant  future  turn  the 
present  situation  into  sheer  chaos 
unless  a  workable  policy  is  developed. 
Present  policy  is  the  responsibility  of 
the  FCC.  whtch  has  neither  the  re- 
sources nor  mandate  for  enforcement. 
One  typical  Issue  is  freedom  of  speech 
as  affected  by  FCC  controls,  CB  is 
already  used  in  organized  demonstra- 
tions; this  raises  the  question  of  the 
legality  of  police  use  of  jamming  to 
maintain  taw  and  order  in  riot  situa- 
tions. Privacy  and  the  use  of  scram- 


blers versus  monitoring  for  illicit  use  is 
another  example.  At  least  eight 
federal  government  agencies  (FCC, 
OTP,  Commerce,  State,  Justice,  Coast 
Guard,  Defense,  Interior)  and  local 
governments  will  have  to  contend 
with  the  potential  impact  of  CB. 

USPS  Headed  for  Obsolescence? 

Already  beleaguered,  the  United 
States  Postal  Service  (USPS)  is  per- 
ceived by  the  report  as  one  of  the 
more  vulnerable  organizations  tn  the 
path  of  the  telecommunications  on- 
slaught. Despite  the  vital  function  it 
has   performed   for  society  for  two 


The  Persuader 


A  Boston  psych  ratrist  says  CB 
radio's  effect  on  personality  may  be 
too  new  a  phenomenon  to  draw  any 
accurate  conclusions.  Dr.  Mark  Walter 
of  the  McLean  Hospital  in  Belmont 
says  it's  a  matter  of  people  feeling  the 
power  and  anonymity  of  the  micro- 
phone. 

Walter  told  the  Boston  Gtotoef  "It's 
really  a  new  variation  of  an  old  thing 
, , ,  we  do  know  that  ham  radio 
operators  are  often  the  sort  Of  people 
who  enjoy  being  in  a  room  alone  with 
the  power  of  talking  out  to  the  world 
They  want  to  reach  out  and  be  in 
touch  with  people  but  keep  an 
emotional    distance    Irom    the   same 


people." 

FCC  regional  director  Gerard  Sat  no 
goes  a  step  further,  Sarno  charac- 
terizes the  average  CBer  as  a  "nrtwit" 
who  becomes  "obsessed  with  the 
feeling  that  they  have  no  other  pur- 
pose in  life  other  than  to  transmit  on 
a  CB  radio.  It  gives  them  a  source  of 
identity  they  never  had  before.  And 
suddenly,  if  they're  criticized  by 
someone  else,  watch  out  for  them/' 

Both  men  were  commenting  on  a 
recent  shooting  incident  in  Boston. 
Newspaper  accounts  reported  that 
two  friends  were  chatting  over  CB 
when  a  third  person  broke  in  with 
some  flack.  "You  come  over  here  and 


say  that  face  to  face/'  one  of  the 
friends  shot  back,  adding  that  he  lived 
at  an  address  in  the  Back  Bay  section. 

A  short  if  me  later,  in  the  wee 
hours,  a  car  showed  up  outside  the 
Sack  Bay  address.  A  man  jumped  out, 
yelling;  "H&rs  I  am.  Now  what  are 
you  going  to  do  about  it?" 

A  44  year  old  businessman  ran  out 
mto  the  street  to  answer  the  chal- 
lenger, Brandishing  a  .38  caliber  re 
volver,  he  smashed  one  of  the  car 
windows  .  . .  and  pumped  a  slug  into 
the  CB  set  under  the  dash,  demolish- 
ing  it  "There,  that'H  teach  you,"  he 
shouted  back,  as  he  ran  into  his  house, 


Carnival  Time 


The  combined  effort  of  amateur 
radio  operators  in  two  states,  the  Red 
Cross,  and  others,  has  resulted  in  the 
return  of  a  missing  boy  to  his  worried 
mother. 

Mrs.  Judy  Lever,  Ml.  Holly,  Vt„ 
had  high  praise  for  the  amateur  radio 
operators,  who  located  her  son,  Mark, 
13,  when  others  had  not  been  able  to 
find  him, 

Amateur  radio  operators  in  Ver 
mont.  including  Fern  Adams  W1YYU, 
North  Clarendon,  William  Dimick 
WAIOHB,  Rutland,  and  Mildred  Doe 
K1BOB,  Bellows  Falls,  notified  New 
Hampshire  operators  that  the  boy  was 
missing  and  possibly  traveling  with  an 
amusement  company  m  New  Hamp 
shire  or  Maine. 

"I    have    a    Friend   who    is  a   ham 


operator,"  Mrs.  Lever  said,  "Her  set 
was  not  working,  but  she  contacted 
friends,  who  immediately  contacted 
others,  among  them  Mr.  Prescott  (J. 
Longdon  P  resect  t,  amateur  radio 
operator  and  disaster  chairman  for  the 
Kearsarge  Chapter,  American  Red 
Cross,  in  Franklin),  We  told  them  we 
were  looking  for  a  carnival,  and  within 
two  hours  they  had  located  the  com 
pany  and  my  son,  i  am  very  grateful 
to  them  for  the  fine  job  they  did." 

Amateur  activities  were  coor 
dinated  by  Edwin  Antz  of  Banbury, 
net  manager  of  the  Grange  State 
Amateur  Radio  Network,  and  the 
WR1ABU  repeater,  located  in  Con- 
cord. 

The  particular  company  Mark  was 
traveling  with  was  difficult  to  trace,  as 


they  moved  often.  The  help  of  Mrs. 
Linda  Heben.  Carver  Street,  West 
Franklin,  and  amusement  publica- 
tions, determined  that  the  boy  was 
with  an  amusement  company  in 
Calais.  Maine. 

The  Red  Cross  and  company 
officials  made  arrangements  to  trans- 
port Mark  back  to  Mt>  Holly,  but  a 
misunderstanding  about  time  resulted 
in  Mark  taking  a  bus  home  on  Mon- 
day- 
Mrs.  Lever  was  happy  to  have  her 
boy  back  home,  and  Mrs.  Hebert  has 
been  commended  by  the  Red  Cross 
for  her  efforts  In  locating  the  missing 
boy. 

Reprint &d  from  the  Manchester  {N.HJ 
Union  Leader,  July  21 1  t976. 


centuries,  the  USPS  has  limited  free- 
dom with  which  to  combat  the  en- 
croachments which  have  begun.  Elec 
tronic  funds  transfer  techniques 
already  in  use  can  significantly  sub- 
stitute for  the  35  percent  of  all  mail 
(two  thirds  of  first  class}  accounted 
for  by  financial  transactions  {orders, 
invoices,  bills  and  payments),  Because 
Postal  Service  operating  costs  reflect 
the  number  of  deliveries  which  need 
to  be  made,  not  the  volume  carried, 
the  loss  will  disproportionately  affect 
USPS  revenues. 

A  second  threat  lies  in  the  growth 
of  digital  data  and  facsimile  networks 
which  might  ultimately  be  used  for  a 
large  portion  oi  intra  and  inter- 
business  messages.  With  advancements 
like  these  making  mail  service  obsolete 
for  many  business  purposes,  massive 
subsidization  might  be  required  to 
maintain  national  mail  service  for  in- 
dividuals, This  could  result  in  very 
much  steeper  postal  rates 
{approaching  35d  an  ounce  for  first 
class  mail  in  the  mid  1980s!,  the  need 
to  pick  up  mail  from  central  drops,  or 
else  pay  for  deliveries. 

The  USPS  can  respond  with  its  own 
electronic  transmission  to  move  mail 
from  one  location  to  another.  How- 
ever, the  most  profitable  portion  is 
what  is  handled  by  telecommunica- 
tions companies  which  can  avoid  the 
expensive  physical  delivery  process. 
Uniess  the  USPS  is  prepared  and 
permitted  to  compete  directly  with 
private  industry,  it  must  build  its 
business  out  of  the  least  economically 
desirable  markets. 

Television  Struggle 

A  third  scenario  deals  with  the 
possible  outcome  of  an  attenuated 
struggle  between  "free"  broadcast 
television  end  cable  and  pay  tele- 
vision. The  potential  for  competitive 
advantage  afforded  by  the  use  of 
satellites  might  ultimately  lead  to  the 
elimination  of  local  TV  broadcast 
stations.  Alternatively,  current  re- 
search into  the  use  of  optic  fibers 
could  lead  to  telephone  companies 
becoming  the  most  logical  providers 
of  home  television  access  in  the  long 
term.  Regulatory  policy  wilt  continue 
to  be  a  key  factor  in  alternative 
developments  and  any  subsequent 
change  in  the  television  industry's 
infrastructure,  The  FCC  and  other 
regulatory  agencies  now  face  in 
creasing  conflict  as  technology  offers 
new  opportunities  that  favor  first  one 
telecommunications  industry  sector 
and  then  another. 

Another  scenario  explores  the 
possibility  of  two-way  broadband 
communications  being  extended  to 
cover  individual  households,  permit- 
ting access  from  homes  to  libraries, 
data  bases,  education,  entertainment, 
computers,  and  other  facilities.  A  fifth 
scenario  investigates  the  interface 
between  public  services  and  private 
enterprise  in  the  provision  of  telecom- 
munications services  for  health,  educa- 
tion, and  government  communication 
needs. 

Arthur  D.  Little.  Inc. 
Cambridge  MA 


8 


The  Federation  of  Eastern  Massa- 
chusetts Amateur  Radio  Associations 
has  been  putting  on  conventions  for 
years  now.  There  have  been  those 
bigger  than  this  year's  version,  held  at 
the  downtown  Boston  Statler  Hilton. 
Most  of  the  biggies  had  come  to  the 
now  departed  Mew  Ocean  House  in 
Swamp sco tt,  but  that  was  before  the 
CB  explosion. 

Not  that  the  CB  influence  hurt 
attendance  much.  A  lot  of  CBers 
turned  out,  just  to  see  why  all  those 
folks  were  breaking  channel  f  9  to  find 
the  hotel.  Convention  officials  said 
they  had  a  record  day  Sunday  .  .  ,  but 
the  exhibitors  were  another  story. 
Less  than  fifty  showed  up,  and  five  of 
those  were  computer  oriented.  Several 
manufacturers  said  they  were  using 
the  same  displays  at  CB  conventions, 
by  simply  inserting  new  signs  (to 
change  that  loaded  whip  exhibit  from 
27  to  144  MHz),  The  economics  of 
the  CB  boom  then  became  one  of  the 
unspoken  exhibitors. 

A  highlight  of  the  weekend  was 
WRIACO's  long  distance  link  with 
WR6ABM  in  the  San  Francisco  Bay 
Area,  The  Maiden  association  has 
done  it  before,  with  a  July  4th  spec- 
tacular that  linked  Boston  with 
Hawaii  and  Philadelphia.  But  this 
time,  instead  of  the  club  paying  the 
bill,  the  cost  {about  $150)  will  be 
borne  by  a  small  group  of  Boston 
FMers,  A  high  point  (or  low  point, 
depending  on  how  you  took  at  it)  was 
one  poor  fallow's  query,  aired  on  both 
coasts,  whether  it  was  just  conditions 
or  what?  He  even  signed  his  call!  Plans 
to  broadcast  remarks  by  ARRL  Presi- 
dent Harry  Da  nna  Is  W2TUK  during 
the  convention  banquet  had  to  be 
scrapped,  because  of  problems  on  the 


Report  from  Boston 


West  Coast  side.  But  once  the  system 
was  debugged,  all  went  well, 
WR6ABM,  incidentally,  is  micro- 
processor controlled. 

Sack  at  the  convention  .  . ,  Heath 
was  introducing  its  new  synthesized 
2m  FM  rig,  the  HW^2036.  An  earlier 
attempt,  youMf  remember,  was 
recalled  because  of  spur  problems, 
although  company  engineers  say  the 
earlier  model  would  have  worked,  if 
most  hams  had  access  to  spectrum 
analyzers.  Heath  says  the  new  version 
puts  spurs  (within  20  MHz  of  carrier 
frequency)  down  70  dB.  It's  due 
before  Christmas. 

A  close  competitor  wifl  be  the  Icom 
IC  22S,  a  22  channel  synthesized  2m 
FM  rig  which  features  a  diode  matrix 
system  for  user  setup  of  desired 
channels.  The  Icom  was  the  talk  of 
the  convention,  with  dealers  taking 
scores  of  orders  and  much  speculation 
about  the  new  model's  impact  on  the 
2m  market.  It  looks  like  the  22S  will 
become  a  modifier's  delight,  with 
several  schemes  already  afoot  to  exter- 
nally program  the  synthesizer  through 
outside  switching.  Company  officials 
say  demand  is  so  great  that  it  could  be 


months  before  the  orders  are  filled, 
But  they  continue  to  deny  that  the 
IC  230  is  about  to  follow  the  IC  22 A 
into  oblivion.  Rumors  nevertheless 
persist  that  Tempo's  VHP  1  digital 
readout  rig  will  soon  have  an  Icom 
competitor. 

On  the  HF  side  .  . .  Kenwood  Trio 
kept  a  constant  crowd  with  their  new 
TS-820r  despite  the  fact  not  one 
dealer  at  the  convention  had  any  to 
sell.  Kenwood  officials  noted 
increasing  pressure  for  them  to  sell 
direct,  a  violation  of  longstanding 
company  policy,  and  could  only  urge 
people  to  keep  pfugging  at  their  focal 
dealers,  Gush  Craft  introduced  a  new 
four  element  tri-band  beam,  model 
ATB-34.  With  an  18'  boom  and  30'8" 
maximum  element  length,  it's  bound 
to  stir  up  the  tri-band  market.  One 
real  plus  is  CushCraft's  plan  to  include 
a  1-1  balun  as  part  of  the  deal  The 
first  ones  ought  to  be  coming  off  the 
assembly  line  soon. 

Hy-Gain     has    apparently    applied 
some  of  its  CB   R&D  money  to  the 
ham  bands,  with  a  new  line  of  VHF 
UHF   mobile  antennas.  They   use  an 
etched  copper  loading  coif  on  a  PC 


board  and  even  offer  one  that  covers  6 
and  2m.  The  idea  first  appeared  with 
Hy-Gain  CB  antennas. 

One  of  the  biggest  disappointments 
had  to  be  the  convention  flea  market. 
For  two  days  some  die-hards  hung  in 
there,  but  the  downtown  location 
took  its  toll,  since  the  pickings  were 
so  poor.  To  say  the  least,  Boston  was 
no  bargain  for  flea  marketeers. 

Ail  that  aside,  it  was  a  pretty  good 
convention.  All  the  elements  (except 
the  fleas}  were  there  . . .  and  the 
Boston  crew  came  through  with  their 
usual  outstanding  prize  program 
{everything  from  a  weather  station  kit 
to  a  TR-4C},  One  big  change  was  the 
mounting  influence  of  microprocessor 
hamming.  The  seminar  schedule  was 
loaded  with  it,  and,  with  3  retailers 
and  an  equal  number  of  manufac- 
turers in  evidence,  it's  apparent  that 
ham  radio  is  in  for  another  revolution. 
Typically  it's  in  for  another  round  of 
controversy  as  well,  as  the  debate 
Over  microprocessors  gets  underway  in 
earnest. 

Warren  ENy  WA1GUO /I 
Bennington  NH 


Using  the  airwaves  and  lots  of 
goodwill,  a  band  of  local  ham  radio 
operators  cut  through  international 
red  tape  to  airlift  a  seriously  ill  Ameri- 
can from  Mexican  to  a  hospital  here, 

Robert  Lake  Garden  Jr.,  27,  of  New 
York  state,  was  in  Veterans  Hospital 
today  after  the  San  Diego  County 
Amateur  Radio  Council  put  up 
$1,700  bail  for  alleged  crimes  in 
Mexico  and  flew  him  here  in  a  rented 
pfane  piloted  by  a  local  ham, 

Members  of  the  club  pot  the 
original  bail  reduced  from  S9.000  to 
$1,700;  a  member  put  up  alt  the 
money  at  once  pending  pledges  that 
were  made  over  the  radio. 

Another  member  rented  a  four- 
seater plane  and  flew  down  to  Mexi- 
cali  yesterday,  the  bail  was  paid  and 
the  Mexican  Red  Cross  rushed  Garden 
to  the  border  at  Calexico. 

The  Fire  Department  there  supplied 
another  ambulance  which  sped  to  the 
airport,  where  Garden  was  placed  in 
the  plane  and  flown  to  Montgomery 
Field.  He  satd  very  little  on  the  flight. 

An  ambulance  service  waived  its 
customary  fee  and  took  the  heavily 
sedated  man  to  the  hospital 

Doctors  there  were  conducting  a 
series  of  tests  to  determine  the  exact 
nature  of  Garden's  illness.  He  had  told 
some  of  the  hams  that  he  was  dying  of 


Hams  to  the  Rescue 


throat  cancer  and  could  not  get 
proper  treatment  in  Mexican. 

Garden's  flight  to  freedom  began  a 
few  weeks  ago  as  he  lay  in  the  general 
hospital  at  Mextcali..  He  told  Umberto 
Wang,  a  medical  student,  that  he  was 
dying  of  throat  cancer  and  wanted 
American  ham  operators  to  contact 
his  mother  in  New  York. 

Wang  happens  to  be  a  ham,  end 
passed  the  message  along  to  a  feflow 
Mexicali  ham  who  he  knew  was  in 
contact  with  hams  on  this  side  of  the 
border. 

Jim  Smith  of  OcotiMo,  who  belongs 
to  the  San  Diego  ham  outfit,  picked 
up  the  call  and  relayed  it  to  many  of 
the  4/000  members  of  the  group.  One 
of  them  called  Garden's  parents,  who 
said  they  had  no  money  to  help. 

Interest  in  the  issue  spread  quickly. 


and  a  "Rescue  Robert"  fund  was 
established  with  the  goal  of  bringing 
the  man  out  of  Mexico.  San  Diego 
hams  appealed  for  help  to  the  U.S. 
consulate  in  Tijuana,  but  were  unable 
to  obtain  assistance. 

Paul  Bower,  a  local  ham  who 
piloted  the  plane  yesterday,  explained 
how  Garden  came  to  be  in  custody 
according  to  what  the  man  told 
Smith.  The  Ocotillo  man  visited 
Garden  often  during  his  many  trips  to 
discuss  the  matter  with  Mexican  offi 
cials. 

Carden  told  Smith  he  lives  in  Lock- 
port,  N.Y.,  and  served  three  years  in 
the  Marine  Corps,  He  was  on  the  West 
Coast  in  April  visiting  friends. 

In  Barstow,  he  met  a  man  and  two 
girls  who  invited  him  to  go  to  Mexico 
with    them,    he   said,   and    the  group 


visited  border  cities. 

One  of  the  girte  paid  for  the  food 
and  lodging  of  the  group  with  credit 
cards  she  said  belonged  to  her  mother. 
Garden  said.  However,  a  Mexicali 
hotel  man  got  suspicious  and  called 
police, 

The  other  couple  had  fled,  but 
Garden  and  one  gfrl  were  arrested*  The 
girl  was  freed  because  she  was  16; 
Garden  was  jailed. 

But  he  was  hospitalized  when  he 
became  ill  with  what  he  said  was 
cancer  of  the  throat.  He  said  that  he 
had  been  fed  intravenously  for  60 
days  and  would  die  if  not  treated  in 
this  country. 

Johnny  Johnston,  a  ham  who  got 
involved  in  the  case,  went  to  Mexicali 

Continued  on  page  89 


9 


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Looking  14/est 


BiH  Pasternak  WAGfTF 
14725  Titus  ST.  =4 
Panorama  City  CA  91402 

We  have  probably  heard  the  nation 
of  Israel  referred  to  as  the  "Garden" 
of  the  Middle  East,  in  that  from  this 
"desert"  the  Israel  people  have  carved 
a  flourishing  land  of  plenty  —  a  place 
that  they  call  a  "land  of  milk  and 
honey/'  It  seems  as  though  it's  not 
only  ihe  products  of  "old  Mother 
Nature'*  that  have  come  to  flourish 
there#  but  VHF  and  VHF  repeaters  as 
well  How  do  I  come  to  make  this 
statement?  Thanks  to  Yuval  4X4 FN, 
recently  portable  6,  Looking  West  has 
the  opportunity  of  bringing  you  a  fait 
of  Information  as  to  what  Israeli 
amateurs  are  doing  with  two  meters, 

Yuval  was  on  a  trip  to  the  south- 
land when  I  encountered  him  on  the 
WR6ASB  repeater  system  here  in  Los 
Angeles.  To  be  a  bit  more  specific,  he 
was  en  route  from  Los  Angeles  to  San 
Diego  and  had  a  lot  of  time  to  pass  as 
he  headed  south  on  1-405,  After  imro 
ductions  and  the  "warm  PARC 
welcome/*  I  began  to  question  Yuval 
about  what  is  happening  VHF  wise  in 
his  homeland,  with  the  following 
being  a  summary  of  the  information 
that  came  forth  as  a  result. 

At  present  there  are  at  least  three 
operative  two  meter  systems,  all  ope r 
ating  on  the  same  channel  pair  of 
145.175  in  and  145.775  out.  One  of 
the  three  operational  systems  is 
located  in  the  area  of  the  city  of 
Haifa,  another  near  Beersheba,  and 
the  last  at  Kibbutz  Sasa  Isen/ing  the 
Upper  Galilee).  A  fourth  system,  also 
on  the  same  channel  pair,  was  being 
prepared  for  the  Tel  Aviv  area  when 
Yuval  departed  for  the  USA,  Whether 
it  is  operational  or  not  at  this  wrrttng 
is  unknown. 

Now,  unlike  repeaters  here  in  the 
USA,  Israeli  repeaters  do  not  have 
distinctive  call  signs  such  as  the  WRs 


we  have  come  to  know,  and  most 
simply  operate  under  the  call  of  the 
amateur  or  amateurs  responsible  for 
the  installation  of  the  system.  Most  do 
not  have  auto  ID,  so  you  sort  of  have 
to  kerchunk  a  system  to  see  if  it's  on 
the  air.  According  to  Yuval,  "visitors" 
using  these  systems  are  quite 
welcome,  and  American  amateurs 
planning  to  visit  Israel  can  obtain  a 
permit  to  operate  by  contacting  the 
appropriate  ministry  prior  to  de- 
parture to  secure  a  permit,  1  believe 
that  it  was  the  Ministry  of  Communi- 
cation, but  I  am  not  too  sure  since  by 
this  point  signals  were  beginning  to 
drop  out,  Possibly  it  was  the  Ministry 
of  Transportation;  I  will  try  to  clarify 
this  point  in  the  near  future. 

So  much  for  repeater  operation, 
but  for  this  Story.  Simplex  (direct)  is 
also  alive  and  well  and  growing 
rapidly.  The  prime  simplex  channei  is 
the  repeater  output  frequency  of 
145.775,  but  when  that  channel  is 
busy  you  will  find  the  overflow  sitting 
on  both  145,25  and  145.50,  in  that 
order.  In  the  Tel  Aviv  area,  I  am  told 
that  simplex  is  busy  most  of  the  day 
and  we  LI  into  the  evening.  Language 
barrier?  Not  according  to  Yuval,  since 
he  says  that  most  Israeli  amateurs 
speak  fluent  English.  And  with  this 
you  have  a  quick  glance  at  what 
VHF -minded  amateurs  elsewhere  in 
the  world  are  up  to  —  a  chance  to 
glimpse  at  the  achievements  of  others 
in  the  worldwide  community  we 
know  as  amateur  radio.  Now  on  to 
what  we  promised  last  month,  or  at 
least  close  to  it:  a  glimpse  at  a  real 
great  guy  on  a  trip  here  to  the 
southland,  John  B.  Johnston  K38NS, 
Chief  of  the  FCCs  Amateur  and 
Citizens  Division. 

In  case  you  have  not  guessed  it  by 
the  foregoing,  I  happen  to  like  John. 
In  my  personal  opinion  he  is  the  best 
thing  to  happen  to  amateur  radio  in 
the  many  years  that  1  have  been  a  part 


San  Fernando  Valley  A  RC  President  Fred  Killiti  WB6EJC  formally  welcomes 
John. 


of  it.  What  he  has  accomplished  on 
our  behalf  in  just  one  short  year  is 
something  that  he  and  we  can  all  be 
proud  of.  Thanks  to  his  trust  and 
belief  m  us,  and  his  willingness  to 
press  for  more  freedom  from  regula- 
tion so  that  amateur  radio  can  again 
grow  and  prosper,  he  will  long  be 
remembered  within  our  ranks. 

I  had  hoped  to  arrange  a  private 
interview  with  John  while  he  was  here 
in  LA,,  and  had  even  approached 
CapL  Dick  McKay  K6VGP,  John's 
host,  on  the  matter.  Unfortunately, 
due  to  schedule  conflicts  on  my  part, 
no  feasible  time  could  be  found-  The 
simple  fact  was  that  I  had  to  put  in  a 
lot  of  overtime  at  work,  and  that 
limited  my  Free  time  a  bit.  However,  I 
found  myself  in  a  position  to  attend 
and  participate  in  two  evening  open 
meetings  that  John  had  with  area 
amateurs.  Before  continuing,  though, 
and  in  deference  to  John,  1  must  say 
that  the  format  I  will  follow  is  that  of 
transcribing  from  tape  both  the  ques- 
tions and  John's  answers,  close  to 
verbatim.  These  questions  were 
posed    by    members    and    visitors  to 

meetings  sponsored  by  the  Palisades 
Amateur  Radio  Club  in  Cutver  City 
and  the  San  Fernando  Valley  Radio 
Club  in  Panorama  City  /Van  Nuys, 
during  the  week  of  August  16, 

First,  let  us  set  the  scene.  The  place 
is  the  Veterans  Memorial  Hall  \n 
Culver  City,  California,  the  evening  of 
August  18th.  Dan  Dec  ken  WA6FQC, 
President  of  the  Palisades  Amateur 
Radio  Club,  addresses  the  assembled 
multitude.  Dan  proudly  welcomes 
John  to  this  meeting  on  behalf  of 
PARC,  and  introduces  him  to  the 
audience.  This  introduction  is  fol- 
lowed by  a  3  minute  standing  ovation 
—  a  totally  spontaneous  showing  of 
affection  toward  their  friend  from 
back  East. 

John  began  the  formal  part  of  his 
presentation,  after  greeting  the  crowd, 
by  showing  a  series  of  color  slides  that 
told  about  himself:  his  specific  inter- 
ests in  amateur  radio,  his  station,  the 
radio  clubs  he  has  and  does  belong  to, 
and  some  of  his  friends  within  the 
amateur  community.  It  was  a  ''here  I 
am,  come  get  to  know  me  as  a  fellow 
ham"  presentation  that  gave  us  all  a 
bit  more  insight  into  this  "man  from 
the  FCC.f*  Then  came  the  part  that 
most  of  us  had  awaited  -  the  open 
format  question  and  answer  session. 
All  questions  were  made  from  the 
floor  by  fellow  amateurs  just  like  you 
and  me.  The  following  are  what  I  feel 
are  the  pertinent  subjects  covered  in 
both  the  meetings  I  attended  and 
taped. 

Question:  What  about  1979?  (Ques- 
tioner was  referring  to  where  amateur 
radio  will  stand  at  this  upcoming 
conference.) 

John:  We  probably  have  about  the 
best  organized  working  group  of  ill 
the  groups  and  I  say  that  because 
Merle  Glunt,  who  is  the  ARRL  man 
working  on  that,  who  used  to  work 
for  the  FCC  and  is  possibly  one  of  our 
top  international  negotiators,  says 
that  he  attends  all  ihe  meetings: 
broadcast,   common   carrier,    and   so 


forth.  He  says  we  probably  have  the 
best  organized  group,  and  I  also  know 
that  when  we  did  our  report  —  we 
have  to  file  with  the  Library  of 
Congress  —  as  for  the  amateur,  we 
have  the  best  looking  report,  too. 

However,  that's  to  establish  the 
FCC  position,  and  I  think,  shortly, 
before  too  many  months,  there  will  be 
a  first  of  a  series  of  Notices  of  inquiry 
coming  out  with  what  the  FCC  posi 
lion  is.  I  don't  think  we're  going  to 
get  everything  in  that  notice  that  the 
amateurs  asked  for,  because  we  asked 
for  an  awful  lot.  We  asked  for  all  of 
our  present  bands:  for  our  present 
bands  to  be  expanded;  for  some  new 
bands;  and,  you  know,  really  sort  of 
gorged  ourselves  writing  to  Santa 
CI  a  us.  But  the  fellows  working  on  the 
group  have  done  a  fantastic  job. 
Apparently  they're  working  on  a  new 
document  —  that's  the  amateur  group 
—  to  further  support  and  justify  our 
need  for  those  frequencies. 

Some  of  them  (frequencies)  are  in 
trouble,  I  guess  you've  heard  about 
the  one  that's  probably  nearest  and 
dearest  to  your  hearts,  146  to  148 
MHz,  which  is  not  an  amateur  band  in 
some  parts  of  the  world.  I  believe  that 
the  maritime  or  aviation  is  after  that, 
looking  for  more  VHF  frequencies.  76 
meters,  3.9  to  4,0  -  the  broadcasters 
have  their  eyes  on  that.  The  broad- 
casters also  have  their  eyes  on  160 
meters,  so,  who  knows?  It's  going  to 
be  an  uphill  fight  all  the  way. 
Question:  This  docket  20777,  the 
bandwidth  /mode  docket.  What  is  the 
purpose  behind  it? 

John:  We  are  trying  to  deregulate  the 
service  as  much  as  possible.  All  regula- 
tory agencies  at&  under  great  pressure 
to  deregulate  and.  looking  around  the 
FCC,  the  only  service  that  was  really 
asking  for  deregulation  was  the  ama- 
teur service. 

One  of  the  big  problems  amateur 
radio  has  always  had  with  the  Com- 
mission has  been  when  a  new  mode 
came  along  —  a  new  teletype  mode  or 
whatever  it  is-  Slow  scan  came  along; 
that  was  a  problem  for  a  while.  The 
Commission  felt  that  in  order  to 
authorize  someone  to  use  that  mode, 
they  (the  Commission)  would  have  to 
have  the  equipment  to  monitor  and 
intercept  those  messages  to  make  sure 
they  were  const  stent  with  the  rules, 

I  tried  to  make  a  giant  leap  for- 
ward; I  said  that,  well,  maybe  that 
thinking  was  good  for  the  20s  or  30s 
or  something  like  that,  but  it's  harder 
and  harder  to  get  the  appropriations 
to  buy  that  equipment,  particularly 
when  you  say  you  want  to  use  it  to 
monitor  amateur  transmissions  -  it's 
really  tough  to  get  the  budget  for 
that.  So,  let's  try  and  go  with  some 
thing  simpler.  Maybe  not  talk  about 
emissions  —  talk  about  bandwidth, 
Though  it's  recognized  that  amateurs 
don't  have  a  great  capability  in 
measuring  bandwidth,  But  maybe  if 
I  hey  had  the  requirement,  things 
would  develop,  Maybe  not.  But  then 
it  would  open  up  a  whole  new  future, 
especially  for  the  experimenters  who 
wanted  to  experiment  with  new  types 
(of   emissions},   and   maybe   amateur 


12 


radio  could  bring  new  modes  of  com- 
munication to  the  other  services, 
develop  new  modes  of  com  muni  ca- 
rton. 

The  comments  we've  gotten  seem 
to  be  kind  of  divided  between  the 
people  who  are  forward  looking  and 
can  appreciate  thai,  and  those  who 
would  say.  "What  about  AfvT?  . ,  ,  I 
tike  talking  to  my  buddies  on  AM  on 
75  and  I  bought  my  rig  25  years  ago 
and  !  hope  I  never  have  to  buy 
another  one." 

Of  course,  the  League,  you  know, 
did  reject  the  whole  idea,  so  I  don't 
know.  We  really  haven't  scoured 
through  those  comments  yet.  But  we 
were  a  little  disappointed;  we  hoped 
we  would  get  more  from  the  amateur 
community  on  ways  to  solve  this 
bandwidth  measurement  problem.  It 
looked  like  by  and  large  they've  sort 
of  thrown  up  their  hands  and  said, 
"It's  beyond  us/'  which  wasn't 
probably  too  good  of  a  result  —  and 
frankly  I  think  that  we're  probably 
back  to  "'square  one"  looking  for  new 
ideas. 

Question:  What  kind  of  reaction  has 
the  FCC  received  on  the  new  RACES 
docket,  and  do  you  anticipate  any 
alterations? 

John:  (Begins  commentary  with 
funny  anecdote  deleted  here  due  to 
space  limitations  J  Basically,  the  ama- 
teurs came  to  us  with  tales  of  these 
very  serious  abuses  that  the  local 
governments*  the  police  and  fire 
departments,  who  are  eligible  for  their 
own  services,  were  making  of  RACES. 
The  Commission  was  just  about  ready 
to  do  away  with  it  completely;  that  is 
the  Department  of  Defense  thing.  We 
kind  of  presented  the  argument  of 
"Let's  give  it  one  more  chance.  Let's 
take  it  out  of  the  hands  of  the  local 
governments.  If  they've  got  problems 
with  frequencies  and  emissions  avail- 
able to  them  in  their  services,  work 
those  out  within  the  services.  Don't 
try  to  twist  something  in  amateur 
radio  around  the  wrong  way,  and  let's 
try  and  get  it  back  into  the  hands  of 
the  hams*" 

I  don't  have  very  many  checks  on 
that  other  than  that  the  number  of 
applications  coming  in  has  been  very 
small,  I  understand,  and  we  really 
don't  know  whether  it  is  going  to  be  a 
viable  program  or  whether  we  should 
just  go  ahead  and  do  away  with  the 
whole  thing.  I  can't  really  tell  at  this 
point;  I  think  it's  too  early. 
Question:  Two  questions  on  the  band- 
width docket  that  a  lot  of  amateurs 
might  be  interested  in.  First  of  all, 
what  about  the  future  of  ASCII,  the 
computer  code,  and  secondly,  what 
about  the  future  of  amateur  TV  on 
450?  The  bandwidth  docket  would 
essentially  eliminate  fast  scan  amateur 
TV  from  420  to  450  MHz.  What  is  the 
Commission  going  to  do  on  both  of 
these? 

John:  Well,  you  see,  ASCI  I  was  one  of 
the  driving  forces  behind  this,  because 
in  order  to  authorize  it  we  have  to  go 
convince  Congress  to  give  us  the 
money  to  go  and  buy  ASCII  machines 
to  put  in  all  of  our  monitoring  sta- 
tions around  the  country.  You  could 


It  was  SRO  at  the  San  Fernando  Vattey  ARC  for  John's  program' 


put  this  away  once  and  for  all;  then 
you  come  up  with  a  better  code  and 
we  are  still  talking  bandwidth. 

The  television  on  450!  As  you 
know,  there  has  been  quite  a  battle  on 
the  East  coast  with  the  television 
repeaters,  and  it  did  seem  to  be  a 
rather  localized  thing.  In  order  to 
bring  out  some  discussion  on  this,  and 
see  what  in  the  world  do  amateurs 
want  to  do  with  this,  let's  propose 
that  they  move  on  "up  the  band/' 
where  you  can  point  and  say  they 
reaJly  are  doing  some  development 
work.  For  TV  on  450,  it's  awfully 
hard  to  make  a  case  that  "that's 
development  work"  and  so  forth.  On 
12t5,  1296,  it's  a  different  story.  I 
think  that  amateurs  could  make  some 
very,  very  worthwhile  contributions 
there,  but  there  has  been  a  reluctance 
to  go  because  it's  easier  to  get  450 
gear,  as  you  know.  And  we  did  note 
that  out  here,  in  this  part  of  the 
country,  that  you  were  using  450  for 
voice  communications  very  heavily. 
So  we  did  want  to  get  that  question 
out  in  the  open  and  give  ail  sides  a 
chance  to  comment  and  to  raise  the 
issue. 

Question:  Johnny,  I  don't  know 
whether  you  are  aware  of  what  has 
been  going  on  in  the  field  of  amateur 
radio  public  relations,  especially  out 
here,  but  what  do  you  think  of 
amateurs  going  to  Jhe  pub  tic  and 
introducing  amateur  radio  to  them 
like  on  radio,  TV,  etc? 
John:  Fantastic?  Absolutely  fantastic 
You  know,  it  used  to  bother  me  when 
I  was  in  the  rules  branch;  I  used  to 
keep  track,  and  by  golly,  every  time  I 
checked  we  were  losing  an  average  of 
350  licensees  a  month.  350  a  month! 
It  just  kept  going  down  and  down  and 
down,  while  all  the  other  services  were 
going  up.  Now  there  have  been  a 
number     of      things     which     have 


happened 

Of  course,  a  lot  of  people  have  now 
become  introduced  to  the  glories  of 
two-way  radio  by  virtue  of  "that 
other  mrvice"  But  amateur  radio  has 
begun  to  spring  up,  and  a  lot  of  it  has 
to  do  with  the  public  relations  work 
you  are  doing  and  the  work  your 
clubs  are  doing  in  the  training  pro- 
grams. That  really  is  great. 

I  have  heard  Commissioners  in  the 
past  say  that  "hams  were  an  elite 
group"  —  a  closed  group  —  and  they 
really  weren't  living  up  to  all  those 
purposes  in  97.1  and  all  that.  It  really 
warms  the  cockles  of  my  heart  to  see 
trws  (referring  to  the  new  attitude  of 
today's  more  outgoing  amateurs  in 
"going  public" J. 

There's  more  . ,  .  a  lot  more  . . . 
two  cassettes  full,  but  for  this  month 
we  arc    plum  out  of  space.  We  will 


continue  with  John's  comments  next 
month,  along  with  a  few  other 
goodies.  In  the  meantime,  I  wish  to 
express  my  sincere  gratitude  to  Jim 
Davis  WB0SQP/6,  who  "blew  into 
town"  at  the  right  time  and  with  the 
proper  recording  equipment  to  make  a 
lot  of  what  you  read  this  month 
possible;  to  Bill  Orenstein  KH6IAF/6, 
whose  exceptional  expertise  in  the 
field  of  audio  and  public  address 
systems  made  recording  the  San 
Fernando  Club  a  snap;  and  most  of  all 
to  Mr,  John  B.  Johnston  K3BNS,  for 
visiting  with  us  in  our  town  and  at  our 
radio  clubs  and  for  being  the  warm 
and  gracious  individual  he  is.  If  ever 
you  have  a  chance  to  attend  one  of 
John's  presentations  or  should  you  get 
a  chance  to  have  him  as  a  guest 
speaker  at  your  club,  iump  at  the 
opportunity,  You  will  be  glad  you 
did. 


John  is  greeted  by  Lenore  Jensen  W6NAZ,  ARRL  public  relations  assistant  for 
Southern  California  and  "amateur  radio's  most  charming  fady. " 


13 


Editor: 

Roben  Baker  WB2GFE 
t5  Windsor  Dr. 
Atco  NJ  08004 


m^—^^ 


Please  send  ait  contest  information 
directly  to  me  at  the  address  fisted 
above,  preferably  at  feast  three 
months  before  the  date  of  the 
scheduled  event  In  other  words,  the 
announcement  for  art  event  on  May  f, 
f9??4  should  hopefully  be  submitted 
by  February   7,    7977. 

TAG  CONTEST 
Starts:  1800  GMT 

December  4 
Ends:  1300  GMT 
December  5 
Entries    may   be   single   or   multi- 
operator  class.  All  contacts  on  3,5  to 
3.6   MHz,   CW  only.   General   call   is 
"CQGMR" 


EXCHANGE: 

R  ST/001     and     progressive 
numbers  from  001 , 


QSO 


SCORING 

Contacts  with  own  country,  1 
point;  each  call  area  in  W/K,  UA  etc, 
VE/VO,  and  VK  counts  as  separate 
country.  Contacts  with  stations  in 
same  continent,  2  points;  other  con 
tinents.  5  points.  Contacts  with  HQ 
station  GW8WJ  or  GW6AQ  count  25 
points.  Total  score  is  sum  of  contact 
points  times  total  number  of  prefixes 
worked  (same  as  for  WPX), 

ENTRIES: 

Logs  must  be  sent  not  later  than 
January  31,  1977  to:  Peter  Lumb 
G3tRMP  14  Linton  Gardens,  Bury 
Saint  Edmunds,  Suffolk  IP33  2DZ, 
ENGLAND. 


ARRL  160  METER  CONTEST 
Starts;  2200  GMT  Friday 

December  4 
Ends:  1600  GMT  Sunday 
December  S 
The  7th  annual  ARBL  160  Meier 
Contest  is  open  to  alt  amateurs  on  CW 
only.    Multi-operator    work    is    per- 
mitted and  scores  will  be  listed  separ- 
ately In  the  results,  but  they  will  not 
be  eligible  for  certificates. 

EXCHANGE: 

RST  and  ARRL  section  or  country. 

SCORING: 

QSOs  with  amateurs  in  an  ARRL 
section  count  2  points;  QSOs  with 
amateurs  not  in  an  ARRL  section  are 
worth  5  points.  DX  to  DX  QSOs  do 
not  count.  Multiplier  is  the  total 
number  of  ARRL  sections  174).  VE8, 
and  foreign  countries  worked. 

AWARDS: 

Certificates  will  be  awarded  for 
section  and  non  W/VE  country  high 
scores.  Division  high  scores  wiN  have 
their  section  award  endorsed  with  an 
appropriate  seat 

FORMS: 

It  is  suggested  that  contest  forms  be 
obtained  from  ARRL,  225  Main  St., 
Newington  CT  06111.  Check  sheets 
are  not  required  but  a  penalty  of  3 
additional  contacts  will  be  made  for 
each  duplicate  contact. 

These  rufes  were  taken  from  last 
year's  contest.  For  complete  rules,  see 
the  November  issue  of  QST. 


- 

^^^~-~ 

— 

1 , — __ 

Dec4    5 
Dec4-5 
Oecll  -  12 
Dec  11     12 
Jan  1 

Jan  15-  16 
Feb  19  ■  20 
Mar5-6 
Mar  26  27 
Apr  12-13 
Apr  26    27 


ARRL  160  Meter  Contest 

TAC  Contest 

ARRL  10  Meter  Contest 

Hungarian  DX  Contest 

Straight  Key  Night  (ARRL) 

QRP  Winter  Contest 

YLRL  YL  OM  Contest  -  Phone 

YLRL  YL-OM  Contest  -  CW 

CQ  Worldwide  WPX  SSB  Contest 

YLRL  DX^YL  to  Stateside  YL  Contest 

YLRL  DX-YL  to  Stateside  YL  Contest 


CW 
Phone 


Note:    The   official   dates   for  the   1977   ARRL   contests   had   not   bean 
announced  at  the  time  of  this  writing,  Tentative  dates  should  be: 


Jan  1  -  2 
Feb  5    6 
Feb  5-  13 
Feb  19  -  20 
Mar  5  -  6 
Mar  19  ■  20 


VHF  Sweepstakes 
DX  Contest  -  Phone 
Novice  Roundup 
DX  Contest  -  CW 
DX  Contest  -  Phone 
DX  Contest  -  CW 


ARRL  10  METER  CONTEST 
Starts;  1200  GMT  Saturday, 

December  11 
Ends:  2359  GMT  Sunday, 

December  12 
The  contest  is  open  to  all  amateurs 
worldwide.  All  QSOs  must  take  place 
on  10  meters  and  OSCAR  QSOs  are 
valid-  Each  station  can  be  worked  on 
phone- to- phone  and  CW-to-CW,  and 
anyone  can  work  anyone.  Ail  CW 
contacts  must  be  made  between  2B.0 
and  28.5  MH;,  unless  working 
Through  OSCAR,  When  operating  on 
10  meters,  please  avoid  the  OSCAR 
downlink  frequencies. 

CLASSES: 

Entries  will  be  classified  as  either 
single  or  multiple  operator  stations, 
Multiple  transmitter  stations  are  not 
allowed, 

EXCHANGE: 

All  W/VE  stations  wilt  send  RS(T) 
and  state  or  province.  Others  will  send 
RS(T)  and  consecutive  serial  number 
starting  with  GOT  Stations  that  are 
not  land  based  will  send  RStTJ  and 
ITU  Region  (1,  2  or  3J.  The  District 
of  Columbia  is  counted  as  part  of 
Maryland. 

SCORfNG: 

Each  completed  QSO  counts  2 
points,  or  4  points  if  with  a  W  or  K 
Novice.  The  multiplier  is  the  sum  of 
the  total  number  of  states,  Canadian 
call  areas  (max.  9),  ARRL  countries 
(not  US  or  Canada),  and  ITU  regions 
from  non- land  based  stations.  Final 
score  is  the  sum  of  the  QSO  points 
times  the  total  multiplier. 

AWARDS: 

A  certificate  wilt  be  awarded  to  the 
highest  scoring  single  operator  station 
in  each  section,  Canadian  call  area, 
and  foreign  country.  Region  awards 
for  non-land  based  stations,  and 
awards  for  mutt i -operator  and  Novice 
stations  will  be  issued  if  warranted. 

FORMS: 

It  is  suggested  that  contest  forms  be 
obtained  before  the  contest  from 
ARRL,  225  Mam  St.,  Newington  CT 
061 1 1 ;  include  an  SA3E.  Check  sheets 
are  not  required  but  a  penalty  of  3 
additional  contacts  will  be  made  for 
each  duplicate  contact. 

These  rules  were  taken  from  /est 
years  vomest.  For  complete  rufes,  see 
the  November  issue  of  GST. 

HUNGARIAN  DX  CONTEST 

Starts*  1600  GMT  Saturday, 

December  11 

Ends;  1600  GMT  Sunday, 

December  12 

The  contest  is  sponsored  by  the 

Hungarian   Radioamateur  Society  and 

is  open  to  any  licensed  radio  amateur. 


AH  amateur  bands  from  80  to  10 
meters  may  be  used  on  CW  only. 
General  call  is  "TEST  HA"  while 
Hungarian  will  give  'TEST  WW/' 
Entries  may  be  in  any  of  the  following 
classes:  single  op,  single  band;  single 
op,  mufti-band;  or  muUi-op,  multi- 
band. 

EXCHANGE: 

RST  and  continuous  serial  number 
from  001 ,  After  their  signal  report, 
Hungarian  stations  will  give  a  two 
letter  code  for  their  location  (county J 
as  follows:  BA,  BPf  BE,  BN,  SO,  CS, 
FE,  GY,  HA,  HEr  KO,  NO,  PE,  SA, 
SO,  SZ,  TO,  VA,  VE,  ZA. 

SCORING: 

Each  HA  QSO  counts  1  point.  The 
same  station  may  be  worked  only 
once  per  band.  Each  different  HA 
county  worked  counts  1  multiplier 
point  per  band.  Final  score  is  total 
QSO  points  times  sum  of  multiplier 
points  from  each  band 

ENTRIES: 

Logs  must  be  made  in  usual  form 
with  summary  sheet  and  signed  dec  tar 
ation.  They  should  be  mailed  within  6 
weeks  after  the  contest  to:  Radio 
Amateur  League  of  Budapest,  H-1553 
Budapest,  P.O.  Box  2,  HUNGARY. 

AWARDS: 

Certificates  to  first  place  station 
from  each  country  in  each  class  or 
section.  Additional  places  (f  war- 
rented. 

ARRL  STRAIGHT  KEY  MIGHT 
0100-0700  GMT  SATURDAY 
JANUARY  1 
Check  QST  for  any  changes  in  the 
rules! 

Basically,  rules  require  the  use  of  a 
straight  key  only.  Send  "SKN"  in- 
stead of  "RST''  during  QSOsP  to  help 
identffy  contest  stations.  On  80-40-20 
meters,  try  060  to  080  kHz  up  from 
the  bottom  edge  of  the  band.  On 
Novice  bands,  try  10  kHz  up  from  the 
bottom  of  the  Novice  band,  After  the 
contest  period,  send  a  list  of  calls  of 
the  stations  contacted  during  she  con- 
test period,  plus  your  note  for  the 
best  fist  heard.  Please  mail  entries  as 
soon  as  possible  to  ARRL,  225  Main 
Street,  Newington  CT  0611 1 . 

SOWP  CHRISTMAS  QSO  PARTY 

The  Society  of  Wireless  Pioneers 
will  conduct  a  membership  on- 1 he-air 
QSO  Party  on  the  weekend  of  Decem- 
ber IB  and  19,  1976,  The  party  will 
cover  the  full  48-hour  GMT  period 
and  will  be  the  first  "Voice"  party 
scheduled  by  the  Society.  The  pur- 
pose of  the  affair  will  be  to  give 
members  an  opportunity  to  meet  one 
another  and  to  pass  along  their 
season's  greetings,  etc.  There  will  be 


14 


no  formal  exchange  requirements  and 
no  need  to  submit  logs. 

All  members  with  a  phone  capa- 
bility are  encouraged  to  participate. 
The  call  will  be  CQ  SQWP  While  there 
will  be  no  certificates  awarded,  every- 
one who  takes  part  will  be  a  winner 
by  having  an  opportunity  to  renew 
old  friendships ,  establish  new  ones 
and  to  continue  a  comaradene 
developed  over  the  years. 

Suggested  frequencies  for  the  affair 
are  25  kHz  (±)  5  kHz  up  from  the  low 
end  of  the  General  class  phone  por- 
tion of  each  amateur  band. 

BUDAPEST  AWARD 
This  award  was  originally  founded 
in  1963,  but  the  rules  were  changed 
effective  January  1st,  1976  as  follows: 

The  certificate  is  Issued  in  one  class 
and  may  be  received  only  once.  There 
are  no  endorsements.  Contacts  are 
valid  after  January  1,  1959,  but  each 
station  may  be  used  only  once  m  your 
application.  Any  amateur  band  end 
mode  may  be  used  including  active 
land  or  air  VHF/LIMF  repeaters. 
European  stations  must  contact  75 
HAS  or  HG5  stations,  while  DX  sta- 
tions (including  US)  need  only  con- 
tact 25.  On  VHP,  only  50  different 
HA/HG5  stations  or  5000  kms  sum- 
marized distance;  any  contacts  made 
via  satellites  or  via  the  moon  count 
with  500  kms/OSO  value.  Send  a  list 
of  your  contacts  and  10  IRCs  to  the 
Award  Manager  of  BRALr  Dezso 
Tarcsay  HASH  A,  H-1553  Budapest, 
P-O,  Bo*  2,  HUNGARY.  The  award  is 


also  available  for  SWLs  on  a  "heard" 
basis  with  the  same  rules  and  fee. 

BICENTENNIAL  WORKED 
ALL  STATES  NET  AWARD 

The  Bicentennial  Worked  All  States 
Net  that  meets  on  3905  kHz  nightly 
at  0500  GMT  is  now  offering  its 
award  for  working  all  states  during  the 
Bicentennial  year.  All  contacts  must 
be  made  on  the  net  frequency  during 
net  operation  or  at  least  within  one 
hour  of  the  beginning  or  closing  of  the 
net,  They  must  be  made  from  the 
same  QTH  (or  from  locations  not 
more  than  25  miles  apart)  $nd  con- 
firmed in  writing.  Cost  of  the  award  is 
S2+00  and  OSLs  need  not  be  sent, 
only  an  application  form  verified  by 
another  amateur  is  requested.  For  an 
application  and  complete  information 
contact  Gene  Dens  more  AA4WCG, 
2125  Cambridge  Drive,  Tallahassee  FL 
32304.  By  the  way.  the  awards  will 
not  be  numbered  or  dated  other  than 
1976,  so  there  is  no  rush  or  time  limit 
other  than  making  the  required  con- 
tacts during  1976! 

WORKED  ALL 

NEW  HAMPSHIRE 

The  Concord  Brasspounders,  Inc., 
of  Concord,  HMff  are  again  making 
available  to  all  qualified  amateurs 
their  Certificate  of  Achievement  for 
working  and  confirming  all  ten  New 
Hampshire  counties.  The  ten  GSL 
cards  or  a  request  for  information 
should  be  sent  to  Basil  Cutting  W1JB, 
Suncook,  N.H.  03275. 


rtrrfjrf 


RESULTS  OF  1976  BERMUDA  CONTEST 
Top  A/A  Swoons: 


CW 

Phone 

K2BT 

11,2S3pts 

W1HFB 

37,170pts 

VE1CD 

10,668 

W4UPJ 

21.942 

WA2DIG 

6,402 

K2BT 

19,032 

W0OUE 

6,384 

VE1AGH 

17,346 

W90HH 

5,451 

W1D0 

1 4,076 

Top  U.K.  Stations: 


CW 

G3FXB 

32,637 

G4BUE 

22,176 

G4CNY 

14,739 

Isiand  Winners 

■ 

CW-G4BKI/VP9 

Phone 

G4GI 

46,494 

G3VPW 

24,420 

GW4BLE 

23,904 

Phone  — 

VP9IB 

Oscar  Orbits 


Oscai  6 


Orbital  Information 


Oscar  7  Orbital  Information 


Orlt  it 

Date 

Time 

Longitude 

Orbit 

Date 

Time 

Unyitude 

(Oed 

{GMT} 

of  Eq. 
Crossing    W 

lb* 

(Oec) 

{GMT) 

of  Eq. 
Crossing 

18876 

t 

0146:12 

84,7 

BX 

9350 

1 

0035:16 

58.6 

18888 

2 

0046  08 

69.7 

A 

9363 

2 

0129:33 

722 

18901 

3 

0141:04 

83,4 

B 

9375 

3 

0028:54 

57.0 

18913 

4 

0041:00 

68.4 

A 

9388 

4 

0123:11 

70.6 

1 8926 

5 

0135:56 

82.2 

B 

9400 

5 

0022:31 

55.4 

18938 

6 

0035:52 

67,2 

A 

9413 

6 

0H6:46 

690 

18951 

7 

0130:47 

80.9 

B 

9425 

7 

0016:08 

53.8 

18963 

8 

0030:43 

65.9 

AX 

9438 

8 

0110:25 

67.4 

18976 

9 

0125  39 

79.7 

8 

9450 

9 

0009:45 

52.2 

18983 

10 

0025:35 

64.7 

A 

9463 

10 

0104:02 

65.8 

19001 

11 

0120  31 

78,4 

B 

9475 

11 

0003:23 

50.6 

19013 

12 

0020:27 

63,4 

A 

S488 

12 

0057:40 

64.2 

19026 

13 

0115:22 

77.1 

8 

9501 

13 

0151:57 

77.8 

19038 

14 

0015:18 

62.1 

A 

9513 

14 

0051:17 

6Z6 

19051 

15 

0110:14 

75.9 

BX 

9526 

15 

01 45: 34 

76,2 

19063 

16 

0010:10 

60,9 

A 

9538 

16 

0044.54 

61.0 

19076 

17 

0105:06 

74.6 

B 

9551 

17 

0139:11 

74.6 

19088 

18 

000502 

59-6 

A 

9563 

18 

0038:31 

59.4 

19101 

19 

0059:57 

73.4 

B 

9576 

19 

0132:48 

73.0 

191T4 

20 

0154:53 

87.1 

A 

9588 

20 

0032:09 

57.8 

19126 

21 

0054:49 

72. 1 

8 

9601 

21 

0126:26 

71.4 

19139 

22 

014945 

85.9 

AX 

9613 

22 

0025:46 

56,2 

19151 

23 

0049  41 

70.9 

8 

9626 

23 

0120:03 

69.8 

19164 

24 

0144  36 

846 

A 

9o3S 

24 

0019:23 

54,6 

19176 

25 

Ur^^fC  _  J  4- 

696 

B 

9651 

25 

0113:40 

68.2 

19189 

26 

013928 

83.4 

A 

9663 

26 

0013:00 

53,0 

19201 

27 

0039  24 

68,4 

B 

9676 

27 

0107;17 

66.6 

19214 

23 

0134:20 

82.1 

A 

9688 

2S 

0006:38 

51.4 

19226 

29 

0034:16 

67.1 

BX 

9701 

29 

0100:55 

65.0 

19239 

30 

0129:11 

80.8 

A 

9713 

30 

0000:15 

49.9 

19251 

31 

0029:07 

65.8 

A 

9726 

31 

0054:32 

63.4 

w 


Effective  1  October,  1976,  all  AO-7  mode  8  orbits  which  fail  on  GMT 
Mondays  will  be  designated  as  QBP  orbits,  as  was  done  during  mid-June,  1976. 
The  success  of  the  three  day  QRP  test  has  prompted  these  extra  QRP  orbits, 
and  it  is  hoped  that  users  of  the  AMSAT-GSCAR  7  mode  B  transponder  will 
reduce  their  signals  to  the  recommended  ten  watts  effect iw  radiated  power 
during  these  orbits.  The  use  of  tower  power  is  also  highly  recommended  during 
other  AMSAT  OSCAR  satellite  passes  because  of  the  beneficial  effect  it  has  on 
the  battery.  As  AO  7  grows  older,  its  battery  is  deteriorating,  and  this 
deterioration  is  accelerated  by  users  running  higher  power  than  is  being 
recommended  by  AMSAT  {1 00  Watts  effective  radiated  power).  This  100  Watts 
erp  maximum  is  enough  power  to  produce  very  readable  signals  from  horizon 
to  horizon  with  a  small  antenna  and  the  average  144  MHz  receiving  setup.  If 
mode  B  users  cannot  hear  their  100  Watt  erp  signal  at  all  times  during  a  pass  of 
AQ7,  they  should  look  at  their  receiving  system  and  should  NOT  raise  their 
power  in  order  to  hear  themselves.  With  cooperation  from  all  users,  the 
AMSAT-OSCAR  7  communications  satellite  will  provide  service  for  the 
worldwide  radio  amateur  community  for  years  to  come. 


15 


ou   goons  don 


•    4 


ever   proj-f 


e  ]  t 


.-. 


a  J         :.'it 


V 

hi     s  h 


FORM  A  POSSE 


WA1LET  is  on  the  prowl  after  the 
rip-off  ers-  After  my  friend  WA1SGX 
had  his  2  meter  rig  ripped  off  his  car,  I 
put  my  thinking  cap  on  and  started 
the  wheels  turning,  and  this  is  what  I 
came  up  with, 

I  am  a  member  of  the  "Fidelity 
Amateur  Radio  Club/'  so  l  am  going 
to  propose  a  rip-off  committee,  with 
each  member  equipped  with  an 
Avatanche  transistor  oscillator  In  his 
rig  (commercial  manufacturers  take 
note]  tuned  to  an  outboard  receiver 
{such  as  a  tunnel  diode  job)  so  that  in 
the  event  of  his  set  being  ripped  of  Fr 
he  can  locate  the  direction  his  set  is 
going.  After  the  set  has  gone  beyond 
the  legal  limit  of  the  license  free 
transmissions  set  by  the  FCC,  that  is 
where  the  club  gets  in  the  act,  by 
having  a  club  sponsored  sensitive  re 
ceiver  able  to  tune  to  all  the  club 
members'  frequencies,  giving  a  master 
control  to  direct  the  posse  of  mem 
bars  going  after  the  rip-off  artist  and, 
with  such  aid,  should  be  able  surround 
the  culprit,  giving  the  guy  3  choices: 
turn  him  over  to  the  police,  hang  him, 
give  back  the  radio  with  loot  to  cover 
the  damage  done  to  the  owner. 

Remember  the  old  days.  It  will  be 
like  a  rustler  hunt.  Maybe  I  have  been 
reading  too  many  westerns.  I  believe 
that  only  by  action  on  the  part  of  the 
hams  will  we  be  safe  from  the  easy- 
picking  boys.  Every  club  should  form 
a  protective  committee.  The 
Avalanche  oscillator  is  the  only  oscil- 
lator (I  believe \  that  can  give  a  tre- 
mendous pulse  with  small  power.  All 
the  bright  boys  should  get  busy  and 
send  in  to  73  their  brain  child,  or  send 
to  me,  WA1LET,  so  that  we  can  all 
get  together  and  scotch  the  pilferers*  I 
have  not  had  any  trouble  myself,  but 
have  stuck  my  neck  out  in  the  cause 
of  the  hams,  e.g.,  in  the  dockets  that 
have  been  an  enemy  to  the  hamst  even 
when  it  did  not  affect  me.  I  hope  that 
my  little  gabfest  will  do  a  little  good. 

Cy  Lievesley  WA1LET 

142  8  right  man  St. 

Fall  River  MA  02720 


The  wheels  turned  alright  —  and  made 
mush. 


FAIR  WEATHER  FRIEND 

Congratulations  on  two  major 
counts:  1)  for  bringing  73  to  what  it  is 
and  continuing  to  improve  it,  and  2) 


for  that  editorial  in  the  October  '76 
issue  that  I  Just  read.  I've  read  some  of 
your  '"editorial ism"  in  the  past  that 
has  {on  two  occasions)  caused  me  to 
drop  my  subscription  to  73, 

This  one  shows  class.  This  one  tells 
ft  like  \l  is  -  all  the  way  through  — 
about  the  uPs  and  even  about  the 
contents  of  73  Magazine.  I'm  referring 
(If  you  hadn't  guessed!  to  the  I/O 
Editorial* 

I  like  7 J  because  now,  more  than 
any  other  time  in  its  history,  it  [s  a 
broader- based  electronic  experi- 
menter's journal,  Keep  going,  and 
please  keep  us  informed  regarding 
your  upcoming  Per s- Com p  mag. 

I've  been  hamming  for  about  10 
years,  from  80m  through  450  MHz, 
and  am  just  recently  gaining  a  keen 
interest  in  computer  electronics  — 
especially  uPs. 

Bob  Gromer  WA7NMJ 
Glendale  AZ 

Thanks,   ah    fair    weather    friend,   — 
Wayne. 


FUTURE  SHOCK 


] 


As  I  was  reading  the  August  issue  of 
73  {around  the  fourth  of  July),  the 
article  about  the  computerized  ham 
station  seemed  very  familiar. 

Digging  through  my  vast  collection 
of  73  mags,  I  found  a  story  in  the 
January,  1967.  issue.  The  story  was 
called,  "The  ORZ  Machine/'  and  at 
the  time  was  science  fiction. 

The  "machine"  was  described  as 
being  about  the  size  of  a  portable 
typewriter,  and  was  able  to  copy  CW. 

The  1976  Altai r  microprocessor  is  a 
bit  larger  and  in  the  example  copied 
HTTY,  but  that  ain't  bad  in  just  9 
years. 

Where  would  we  be  today  without 
science  fret  ion  to  encourage  scientific 
experimentation  and  advancement? 

Tom  Grabowski  K3SPY 
Baltimore  MD 


Better  off. 


ABOVE  AND  BEYOND 


] 


Just  a  few  informal  remarks  and 
comments  on  two  of  the  Firms  that 
advertise  in  73  Magazine, 

I  placed  an  order  with  B  &  F 
Enterprises  in  Peabody,  Mass.,  for  two 
speaker  enclosures  as  advertised  in  73. 
Although  they  did  not  advertise  cross 
over    networks,     I    asked     them,    if 


possible,  to  send  me  two  threeway 
crossovers.  The  order  arrived  minus 
one  crossover,  A  communication  fol- 
lowed shortly  after  saying  they  were 
backordenng  one  crossover,  as  they 
only  had  one  for  the  original  ship- 
ment. I  a&ked  them  to  charge  the 
amount  of  the  purchase  to  my  Bank 
Americard.  Now  they  could  have 
charged  me  for  the  whole  order,  but 
they  only  charged  me  for  what  they 
had  shipped,  involving  additional 
paperwork  when  they  shipped  the 
second  crossover,  which  arrived  a  few 
days  later.  Now  this  showed  consider- 
ation and  fairness  with  their  buying 
customers.  Also,  the  shipment  arrived 
so  promptly  that  I  don't  see  how  they 
could  have  checked  out  my  Bank- 
Americard  account  before  shipment. 
It  is  a  pleasure  to  do  business  with 
companies  that  show  consideration  in 
their  dealings  with  the  buying  public, 

I  also  placed  an  order  with  Aldelco 
of  Lynbrook,  INLY.,  for  some  diodes 
and  other  materials,  I  sent  them  • 
postal  money  onfer  to  cover  the 
amount  of  the  purchase,  and  when  the 
order  arrived,  there  had  been  an  error 
filling  the  order  as  they  did  not  send 
me  some  of  the  diodes  that  I  had 
ordered,  and  they  sent  some  that  I 
had  not  ordered.  I  sent  them  a  com- 
munication stating  what  I  had  re- 
ceived and  not  received  and  asked 
them  to  check  my  original  order.  I 
offered  to  send  the  diodes  that  I  had 
not  ordered  back  to  them  on  arrival  of 
the  diodes  that  I  had  ordered,  to  fill 
my  original  order.  A  few  days  later, 
the  diodes  that  were  missing  in  the 
original  order  arrived  with  a  note  of 
apology  and  stating  that  I  did  not 
need  to  return  the  unordered  diodes, 
but  to  keep  them  with  their  compli- 
ments- Now  you  can't  ask  for  any 
thing  more  fair  than  that. 

And  so.  Wayne,  thanks  for  your 
care  in  selecting  advertising  firms  that 
are  reliable  and  considerate  to  adver- 
tise in  73.  It  is  a  pleasure  to  us  readers 
of  73  to  do  business  with  that  type  of 
firm. 

Continued  success  to  you  and  your 
staff. 

J.  Wm.  Anderson  W6QV 
Sun  I  and  CA 


THE  REVOLUTION 


Your  computer  articles  have 
brought  me  up-to-date  after  being  out 
of  the  data  processing  business  lor 
over  four  years.  During  this  time,  I  am 
amazed  at  the  microcomputer  revolu- 
tion, in  terms  of  the  available  proces- 
sing power  for  such  a  small  cost.  As  a 
former  programmer  and  computer 
salesman,  perhaps  you  would  benefit 
from  some  of  my  reflections  on  the 
current  state  of  the  art  -  son  of  like 
the  comments  emanating  from  your 
"Ancient  Aviator/' 

My  first  reaction  to  the  microcom- 
puter revolution  is  simply  that  very 
few  people  even  begin  to  appreciate 
the  problem- solving  horsepower 
possible  with  a  microcomputer.  Back 


in  the  1980s  I  sold  small  scale  business 
computer  systems  {for  a  $100,000 
plus  purchase  price)  that  were  roughly 
comparable  in  processing  power  with 
the  new  6800s  and  8080s  which  art 
available  for  less  than  $10,000  for  a 
disk  system,  In  view  of  this,  it  appears 
that  the  public  must  be  "educated"  in 
terms  of  how  a  microcomputer  can  be 
used  as  a  tremendous  extension  of  the 
mind  to  handle  both  home  and 
business  applications.  To  put  it 
another  way,  less  emphasis  should  be 
placed  on  silly  games  and  more 
thought  should  be  directed  towards 
the  way  to  put  a  microcomputer  to 
work  in  the  household,  hobby  and 
business  world. 

My  second  reaction:  With  the  avail- 
ability of  low  cost  computing,  there  is 
a  need  for  good  self -teaching  pro- 
grammed instruction  manuals  and 
teaching  aids.  It  seems  that,  at  this 
point,  we  have  low  cost  effective 
hardware  with  a  scarcity  of  materials 
capable  of  quickly  acquainting  the 
uninitiated  in  their  use.  If  this  market 
is  to  grow,  this  problem  must  be 
solved  with  self  teaching  applications 
and  programming  manuals,  as  well  as 
manuals  that  will  show  how  this 
equipment  can  be  used  in  solving  the 
day-to-day  problems  for  which  it  is  so 
well  suited. 

My  final  reaction  applies  to  the 
question  of  how  to  best  communicate 
current  know  J  edge  available  to  other 
amateur  radio  operators  like  myself. 
In  this  respect,  it  seems  that  we  need 
to  organize  a  hobby  computer  net 
that  will  meet  regularly  to  disseminate 
useful  information,  If  you  know  of 
such  a  net,  please  let  me  know.  A I  so  f  I 
would  appreciate  having  the  names 
and  addresses  of  any  hobby  computer 
user  groups  which  would  be  willing  to 
share  their  knowledge  with  us  mid- 
westerners  who  are  just  beginning  to 
learn  about  this  west  coast  developed 
technology. 

Robert  E.  Bunn  WA0LKE 

Bunn  Oil  and  Supply  Co. 

508  Porter  Wagoner  Blvd. 

West  Plains  MO  65775 

If  you  get  netted  let  us  know.  Re 
self-teaching,  that's  what  reading  73 
I/O  articles  and  Kilobyte  is  aft  about 


THE  ELECTRONIC  MENSA? 

I've  just  read  the  article  by  Robert 
Fields  in  the  September  73,  and  fault 
it  only  insofar  as  it  fell  short  in  its 
cast  i  gat  ion  of  the  God  Syndrome  ram- 
pant in  amateur  ranks, 

First,  I'm  not  a  CBer  (not  recently 
—  when  CB  was  young,  and  legality 
was  in  vogue,  I  had  a  license,  but  it 
has  long  since  gone  west).  Nor  am  I  a 
ham.  My  familiarity  with  both  code 
and  theory  is  adequate  to  allow  my 
getting  a  General  ticket  tomorrow  if 
so  desired,  but  as  of  this  writing  I  have 
seen  no  facet  of  ham  radio  sufficiently 
challenging  thai  I  should  waste  time 
so  doing. 

Further,  inasmuch  as  the  majority 


16 


of  hams  of  my  acquaintance  are 
pompous,  stuffed  shin  elitists  with 
delusions  of  grandeur,  I  find  no  incen- 
tive in  joining  up  just  for  the  com- 
pany. And,  It  is  this  insufferable  arro- 
gance that  is  turning  off  would-be 
hams  in  droves. 

Also,  let's  forget  that  but  I  about 
horn  radio  being  any  thing  more  than  a 
medium  for  rag  chewing.  The  experi- 
mental phase  went  out  with  the  6L6, 
and  modern  R/0  labs  backed  by 
corporate  financing  are  the  innovators 
now,  not  the  basement  black -box 
builder.  The  day  of  the  lone  inventor 
is  just  about  kaput.  Granted,  hams  are 
using  state-of-the-art  technology  — 
computers,  TV,  etc  -  but  none  of  it 
came  from  ham  circles. 

If  you  ham  types  want  to  multiply 
your  folds,  get  off  your  goddamn 
pedestals,  dismount  from  your  shining 
white  steeds,  and  mingle  with  the 
masses.  Anyone  with  half  a  wit  who's 
had  a  taste  of  modem-day  CB  would 
welcome  ham  radio  if,  in  it,  he  could 
find  the  camaraderie  that  CB\  with  all 
?H  fallings,  offers  on  and  off  the  air.  It 
is  sad  that  in  most  cases  he  encounters 
the  snobbery  of  ham  radio's  electronic 
Mensa,  and.  as  Mr  Fields  says,  trots 
off  to  unload  his  wallet  on  a  Pent  ax 
instead  of  an  ICOM  or  a  Heathkit. 

K.  T.  Derek 
Pittsfield  MA 

Weil,  OM.  there  is  some  Truth  to  what 
you  say  .  .  .  that  part  about  CBers 
being  friendfy.  Other  than  that  it 
appears  to  me  that  you  are  a  sad 
victim  of  what  is  catted  projection  in 
psychological  circles.  If  you  do  decide 
to  give  hamming  a  try,  /  think  you 
may  find,  as  the  rest  of  us  have,  that 
hams  are  about  as  friendly  a  gang  as 
you  could  ask  for  ,  ,  .  they  help  each 
other  , .  .  love  to  talk  .  .  .  and  are 
going  way  out  of  their  way  at!  over 
the  country  to  help  CBers  get  their 
ham  tickets.  Sure  there  are  a  few 
curmudgeons  .  .  .  they  are  there  in  CB 
too,  but  thai  doesn't  change  the 
average  ham  from  being  a  great  guy.  if 
you'd  read  much  of  73  you  would 
know  that  hams  are  in  the  forefront 
of  many  new  technical  developments 
such  as  RTTY,  SSTV,  and  even 
computer  applications.  As  one  of  the 
founders  of  American  Mensa  (1960} 
and  a  member  ever  since  r  I  have 
attended  meetings  in  many  ctties  and 
seldom  have  I  run  up  agatnst  the 
snobbery  you  seem  to  have  found,  if 
that  were  the  caser  Mensa  would  have 
disappeared  long  ago.  f  wonder  what 
other  readers  think  about  hams  being 
snobs?  -  Wayne. 


SATISFIED 

I  am  prompted  to  write  this  both  in 
praise  and  disgust. 

The  praise  goes  to  the  Dataware 
Emergency  Net  for  their  damn  good 
work  during  the  Belie  hurricane: 
Elmer  W3YAH,  Vince  W3SEG  and  all 
the  others  who  pitched  in  and  did 
their  very  besi 


Elmer  lives  on  Lewes  Island,  and 
when  the  island  was  being  evacuated, 
he  said  "As  long  as  I  have  power,  Til 
be  on  the  air,  and  when  I  lose  it,  Til 
go  too."  That  is  ham  radio  above  and 
beyond. 

The  disgust  is  with  the  selfish  slobs 
who  sat  down  right  on  freq  and,  after 
repeated  reminding,  called  CQ  and 
finished  a  QSO„  and  also  with  the  ones 
who  opened  up  with  an  unmodulated 
carrier  for  extended  periods. 

Well,  I  said  it,  and  I'm  satisfied. 
Thanks  for  listening. 

Bill  Simnts  WA2JNV 
Toms  River  NJ 

Jamming  is  a  growing  facet  of  amateur 
radio. 


FEEDBACK 


Please  note  a  correction  to  my 
article,  "ASCH/Baudot  Converter  for 
Your  TVT,"  which  began  on  page  150 
of  the  November.  1976,  issue.  In 
Table  2(b) f  5/Aj  should  be  a  one 
instead  of  a  zero. 

Jeff  Roloff 
Champaign  I L 

Lets  watch  that  stuff,  Rofoft 


COMMON  INTERESTS 


Keep  up  the  good  work  on  73;  it  is 
appreciated.  I  am  not  a  microcom- 
puter nut  (yet),  but  the  articles  are 
interesting  as  I  use  an  IBM  system 
360/370  in  my  work.  The  ads  for 
Mother  Bell  are  an  eye-opener,  espe- 
cially for  those  of  us  who  work  for 
AT&T,  It's  nice  to  see  the  two  com- 
munications interests  {Bell  and  ham) 
cooperating  for  a  change.  Now  if  the 
FCC  will  just  let  us  legalize  tariffs  for 
phone/a utoparch  systems! 

Arv  Evans  K7HKL 
Salt  Lake  City  UT 


GOTTEN 


A  short  comment  on  your  I/O 
Report  in  the  August  issue  of  73  Mag; 
I  think  you  are  really  missing  the  boat 
by  excluding  the  DEC  LSI  1 1  and 
PDP-11 /PDP-8  programs  from  your 
section.  Various  computer  clubs 
around  the  nation  have  acquired  OEM 
status  with  DEC  to  buy  LSMIs  in 
quantities  and  pass  the  low  prices  on 
to  members.  One  club  in  California 
has  helped  over  500  hackers  to  get 
LSI-1  Is.  When  I  was  working  at  DEC, 
the  orders  were  flooding  in.  And  why 
not,  for  the  price  of  an  Altai  r  or 
I  MSA  I  look  what  you  can  get  from 
DEC  .  .  ,  the  LSI  11  Is  about  $650,  an 
interface  is  another  S10C  or  S1 50,  and 
all  you  need  is  a  power  supply  and 
terminal.  No  need  for  a  monitor  pro- 
gram with   the   built-in  ODT  debug- 


ging. And  it  comes  with  4K  x  16  RAM 
standard,  with  power  fail  and  line 
clock  1  They  also  produce  a  PDP-S/A, 
a  single  board  PDP-8  that  would  also 
be  in  the  price  range  of  the  hobbyist. 
On  top  of  all  this,  DEC  has  been 
making  MPS  boards  for  several  years 
that  atso  may  be  of  interest  to 
hackers. 

Bob  Baker  WB2GFE 
AtcoNJ 

/  think  you  got  me  on  that  one, 
Bob.  I  wasn't  thinking  of  the  LSf-71 
when  t  singled  out  the  DEC  PDP-J1. 
There  is  certainty  going  to  be  hobbyist 
(and  other}  software  generated  for  the 
LShl  t  which  might  be  of  interest  to 
I/O  readers,  ff  any  comes  my  way  Hi 
give  it  every  consideration.  And  with 
regard  to  the  PDP-8  ..  .  I  hope  we  see 
software  for  it  coming  into  the  hobby 
community  both  from  simulators 
being  written  (for  an  8080 7  and /or 
from  the  popularity  of  the  Intersil 
6 tOO  getting  a  boost,  —  John, 


from  California  to  Chattanooga  -  and 
we  soon  had  the  problems  resolved. 
The  Software  Board  worked  the  first 
time  I  plugged  it  in  the  Imsai  com- 
puter, 

To  operate  this  board,  one  just 
"examines"  location  FOOD  in  hex  or 
360.000  in  octal  and  then  hits  Run. 
Thereafter  one  enters  programs  using 
the  InteJ  8080  mnemonics. 

73  Magazine  seems  to  have  a  policy 
of  accepting  ads  from  only  reputable 
dealers  who  won't  rip  off  the  ham. 
For  those  hams  considering  entering 
"computronics,"  you  would  do  well 
to  stay  with  such  firms  as  Godbout, 
Hal  Communications  and  those  who 
advertise  in  73.  You  haven't  seen  any 
Trigger  Electronics  ads  lately,  have 
you? 

Nenad  S.  Downing  WB4SLO 
Chattanooga  TN 

Trigger  .  P .  hmmm,  wasn't  he  a  QST 
advertiser? 


GONE  FISHING 


AN  I/O  RECORD 

In  response  to  one  of  your  ads.  I 
recently  purchased  the  God  bout  Soft- 
ware Board.  First,  I  would  like  to 
commend  Godbout  for  their  excellent 
service  and  their  fine  product.  I  re- 
ceived my  order  within  five  days  after 
the  order  was  placed  —  a  record  for 
computer- related  items. 

I  experienced  a  few  problems  in 
interpreting  the  literature.  I  left  my 
number  with  Godbout  and  later  that 
day  Bill  Godbout  returned  my  call  — 


I  have  used  my  back  issue  ham 
literature  to  "bait"  CB  operators.  To 
date  can  count  one  total  convert  and 
several  "nibbles."  Photo  taken  at  my 
portable  QTH. 

Hat  Empie  WA7ZYD 
Duncan  A  2 


INACTIVE  BROTHERS 


This  ts  a  CQ  to  all  hams  who  are 


17 


heart  pacemaker  wearers!  Numerous 
le iters  to  the  ham  journals  indicate  a 
growing  need  for  information  about 
EM!  (electromagnetic  interference  J, 
especially  as  it  relates  to  ham  oper 
ating!  Pacemaker  wearers  generally  do 
not  have  access  to  reports  of  EMI 
susceptibility  teats  made  by  military 
and/or  federally  sponsored 
{FDA/BRH)  testing  programs.  As  a 
result,  the  lack  of  relevant  informa 
tion  leads  to  confusing,  and  often 
erroneous,  "'advice'  from  well- 
meaning  but  ill-advised  individuals 

As  a  pacemaker  wearer  since  April 
T975,  and  a  ham  since  1924,  I  have 
been  compiling  interference  data  in  an 
effort  to  flj  know  my  own  operating 
limitations,  if  any,  and  (2)  to  help  any 
other  hams  with  pacemakers  who  are 
staying  off  the  air  because  of  fear  of 
pacemaker  failure  caused  by  radiation 
from  their  rigs. 

Will  any  reader  who  wears  a  pace- 
maker  write  me  and  describe  any 
experience  which  seemed  to  have  been 
EMI  related?  For  convenience,  and  to 
elicit  the  maximum  information,  I 
have  prepared  a  questionnaire  which  is 
available  for  an  SASE.  This  «  a 
worthwhile  project,  but  many  answers 
are  needed.  For  a  little  bit  of  your 
time  and  a  postage  stamp,  you  could 
get  an  otherwise  inactive  brother  ham 
back  on  the  air  I  QRU? 

W«  R+  (Bill)  Sehoppe 

431  B9  Ave.  N. 

St.  Petersburg  FL  33702 


POINT 


] 


In  answer  to  Dave  Powell 
WA4BRI's  question  in  the  Letters 
column  of  October  "Why  build  in  an 
error?"  with  reference  to  my  "Instant 
Counter  Calibration"  article  in  the 
August  issue  of  73:  There  is  no  error 
from  a  practical  standpoint! 

I  won't  argue  the  position  that 
15,734.265  Hz  is  the  theoretical  color 
horizontal  sync  rate.  In  practice,  how- 
ever, 15,734.26374  Hz  won't  be 
found  any  more  often  than 
15,734.265  Hz  tor  the  simple  reason 
that  the  idea  behind  using  a  rubidium 
standard  in  broadcasting  is  not  so 
much  absolute  accuracy,  as  it  is  long 
term  stability.  The  broadcaster  isn't  as 
interested  in  the  absolute  frequency 
(as  long  as  it  is  well  within  FCC 
tolerances}  as  he  is  in  phasing  his  local 
and/or  remote  equipment  to  one 
stable  standard.  This  circumstance, 
however,  doesn't  make  ustng  the  hori 
zontal  sync  signal  any  less  valuable  for 
the  radio  amateur  because  it  is  the 
most  accurate  signal  available  to  the 
average  ham,  plus  it  is  traceable  to 
NBS  through  the  published  offsets, 

Additional  I y,  as  was  mentioned  in 
my  article,  unless  your  counter  is 
phase  locked  to  the  incoming  signal, 
there  will  be  a  1 1  digit  ambiguity.  My 
Heath  18-1103  would  interpolate  Mr. 
Powell's  figure  of  15,734.26374  Hi  as 
15,734.264  Hi,  and  the  least  signifi 
cant  digit  ambiguity  could  make  this 
either  15,734  263  Hz  or  15,734.265 


Hz.  To  compound  the  dilemma,  the 
guaranteed  one  second  stability  of  the 
Heath  counter  is  .5  ppm  which  in  my 
case  does  indeed  make  the  .08  ppm 
error  WA4BRI  refers  to  seem  insignifi- 
cant. 

My  caution  with  regard  to  making 
sure  that  you  are  tuned  to  a  network 
colorcast  is  aimed  mostly  at  some 
localEy  originated  CATV  (cable} 
system  programs  and  newly  formed 
lowbydget  broadcast  stations  who 
may  not  be  referenced  to  a  rubidium 
source.  I  would  stilt  stand  behind  that 
statement.  The  caution  regarding 
"mini-cam"  units  also  stands,  if  they 
are  in  the  field  and  feeding  back  live 
video  via  microwave  as  the  statement 
in  my  article  implies.  In  thts  case,  they 
are  almost  certainly  not  rubidium 
locked! 

Incidentally,  and  in  closing,  I 
couldn't  help  but  notice  the  piece  in 
QST$  "Hints  and  Kinks"  column  for 
August,  1976  (which  arrives  much 
later  than  73'%  August  issue)  recom- 
mending the  same  procedure  that  I 
cautioned  AGAINST  using,  i.e.,  con- 
necting directly  to  the  TV  receiver 
circuitry  with  the  counter.  I  sincerely 
hope  that  no  one  falls  victim  to 
serious  damage  by  using  the  QST 
approach  (quite  a  J*kinklp). 

David  F,  Miller  K9POX 
NilesIL 

Picky,  picky, 


COUNTER  POINT 


The  letter  by  Dave  Powell  WA4BRI 
in  the  October  letters  regarding  the 
article  "Instant  Counter  Calibration" 
by  David  F  Miller  K9P0X  has  intro- 
duced more  errors  than  it  has  cor- 
rected! 

The  television  networks  employ  far 
more  precision  in  frequency  genera- 
tion than  required  by  the  FCC  rules. 
The  signal  source  as  noted  by  Miller  is 
a  rubidium  atomic  oscillator  for  NBC 
and  C8S  and  a  cesium  atomic  oscilla- 
tor for  ABC  These  sources  synthesize 
5  MHz.  The  color  subcarrier  is 
developed  by  multiplying  5  MHz  by 
63/88,  producing  the  figure  quoted  by 
MiJIer,  3.5795454. 

Next,  take  this  number,  multiply  it 
by  2  and  divide  by  455.  Presto,  you 
have  Miller's  15.734266, 

In  the  future,  it  might  be  helpful  to 
submit  critical  letters  to  the  original 
author  for  comment  before  publics 


'•'-  = 


SCHEMMr/C 


nan. 

The  references  listed  below  contain 
more  information  on  using  color  TV 
Signals  for  caf  ibration. 

1.  Davi*.  D.  D..  "How  To  Use  The  Tele^ 
vision  CqIqt  Signal  For  Calibrating  A  Crystal 
Che Nla tor/'  National  Bureau  of  Standard*. 
November  1974, 

2,  , . ,,  "Daily  Television  Frequency  Trans- 
fer Measurement*/1  Services  BuHelnv 
National  Bureau  of  Standards.  Monthly 
ffnw). 

&  Dj*i*.  Dick  D,.  "CaNbrninfl  Crystal  Oscil- 
lator i  With  TV  Go  lot' Reference  Signal*/' 
ffecRWcs,  Vol,  48.  No.  6.  (iferdi  20. 
I975K  107-112. 

4.  Robbins.  Michael  S.  Calibrating  ft* 
quency  With  Youi  TV/*  Hwdk>-EteQtrQfitc$, 
VoL  47.  No.  9.  (September  1976J,  74-7& 

Michael  S.  Robbins  K6QAH 
Los  Angeles  C A 

You're  qu/te  a  bookworm,  Mike, 


INFLATION,  ETC. 


I  would  appreciate  it  if  you  would 
publish  the  following  in  73  as  soon  as 
possible: 

"REPEATERMEISTER" 
UPDATE 

All  negatives  requested  after  15 
August,  1976V  w"l  incorporate  the 
changes  described  below. 

CW  fD 

ID  initiate  input  IC.  7432,  now  has 
four  initiate  inputs  -  pins  1.  2.  4  and 
5,  Use  330  Ohm  resistors  to  ground, 
This  makes  operation  mote  con- 
venient and  less  wasteful  of  gates. 

Clock  oscillator  lCr  7400.  Use  a  5k 
trimpot  with  a  Ik  V*  W  resistor  in 
parallel.  This  improves  the  operation 
ci  l  i  he  oscillator  and  til  so  inn  us  the 
sending  speed  from  5  wpm  to  about 
25  wpm+ 

TX  hold  transistor,  Q1P  2N708, 
Any  general  purpose  NPN  switching 
transistor  may  be  substituted.  Be  cer 
tain  that  IC  will  not  be  exceeded  by 
the  keying  circuitry  if*  the  transmitter. 
Also,  foil  partem  has  been  modified 
for  the  following  change;  At  the 
collector  of  Q1,  install  two  ger- 
manium diodes  with  the  band  towards 
the  collector  of  Q1  (1N34  or  1N60), 
Jumper  one  djode  to  pins  4  and  6  of 
IC2a.  This  gives  a  5  second  tail  after 
each  ID.  Jumper  the  other  diode  to 
the  collector  of  Q4  on  the  MLB, 
which  is  the  PTT  output, 

MLB 

Pads  have  been  added  to  the  7413 
Schmitt  Trigger  for  the  input-output 


01 


LOCATION 


2  7H 


02 


-Jh 


01 


JM34  0P 
±  IN  SO 


Oi  ~ 

rh 


iC2a 


IC? 
556 


T 


JUMPER 


470  K  , 
IM 


TOCW1D 
BOARD 


500* 

im 


1 1*34  OR 

lOO^F 


f#t 


■vw 


2  -- 


connections. 

Replace  the  jumper  at  IC2  from  pin 
4  to  the  collector  of  Q2  with  a 
germanium  diode,  band  towards  Q2 
A  pad  has  been  added  at  pin  6  for  the 
jumper  from  the  CW  ID  described 
above. 

Receiver  off  timer,  IC3P  555.  On 
some  negatives  pins  6  and  7  are  not 
connected.  Solder  bridge  these  pins 
for  correct  operation. 

Same  goes  for  the  transistors  on  the 
MLB.  Any  NPN  general  purpose 
switching  transistor  may  be  used.  Be 
certain  that  04  can  sink  the  required 
current  from  the  keying  circuitry  that 
follows. 

The  100  Ohm  resistor  on  the  collec- 
tor of  Q3  may  be  increased  to  150 
Ohms. 

The  resistor  value  in  the  schematic, 
2.2  megohms,  at  pins  6  and  7  of  IC3. 
555,  is  the  correct  value,  although  1.5 
meg  is  shown  in  the  parts  layout. 

Pads  have  been  added  for  the  1.8k 
resistor  at  the  base  of  05.  the  auto- 
patch  control  transistor. 

Due  to  increased  costs  of  materials 
(mainly  film),  after  November  1st 
negatives  will  be  $J5  each.  Pre- 
programmed  B223  IC  available.  Your 
chip  and  S4.00  plus  message  desired; 
or  $7.00  and  message  desired,  I  supply 
IC.  Etched  and  drilled  boards  on  G-10 
glass  epoxy  also  available  $7.00  each 
or  both  for  SI 2,00  (limited  supply}. 
Approximately  two  weeks  delivery. 

Geoff ry  W.  Kufchak  WA1UFE 

15  Fourth  Ave. 

Westover  A FB  MA  01022 


OBSESSED 


I  read  those  gripes  in  your  mail 
about  small  computers  In  your  mag.  I 
hope  you  don't  give  in,  A  couple  of 
years  ago  when  I  saw  articles  about 
them  in  the  popular  mags,  I  brushed 
over  them  thinking  they  were  just 
toys  -  Uke  imitations  of  the  n?a/  thing 
{which  of  course  no  one  but  a  genius 
could  understand]. 

Thts  is  my  tenth  month  of  intensive 
concentration  on  them.  I  became  in 
voJved  because  I  wanted  to  translate 
commodity  market  prices  coming  in 
on  a  telegraph  line  into  price  display 
and  possibly  charts  so  I  could  trade 
them  without  losing  so  much  money. 

I'm  building  a  home  brew  affair 
with  Altair  compatibility. 

Knowing  I  would  need  a  display, 
the   "Sol"   terminal   seemed   like  just 


CW  ID 


ittM&t 


TO  04  COLLECTOR    MLB  — 
TO  4CZ4-PINS4.fi' 


■h34  OR 
1N6C 


IK 


-***** ^ 


P  MS  V- 


TK  HOLD 


7400 


***** 


-.-,v- 


*  IN34  OR  IN&Q 


*TUMD£ft  ftQAAQt 


BOA ft&  LOCAtKM 


J        5K 


ia 


the  thing  (Processor  Technology). 
Maybe  I  could  use  it  to  translate  the 
special  hex  code  into  ASCI  I  as  well,  so 
I  ordered  a  circuit  board  end  spent  a 
week  locating  and  sending  for  all  the 
other  stuff  only  to  find  out  they  are 
redesigning  it  and  I  won't  get  the 
board  'til  September.  It's  a  good  thing 
I  haven't  started  on  the  CPU  board, 
because  now  I'm  going  to  have  to  get 
a  Zilogue  board  instead. 

In  other  words,  the  information 
explosion  has  gotten  me.  Not  only  do 
I  have  a  busted  bladder,  but  bleary 
eyes  from  reading  all  that  fine  print  in 
spec  manuals  trying  to  learn  enough 
so  the  thing  will  be  sure  to  work  when 
I  get  it  finished.  {Could  it  ever  be?) 

You  guessed  it.  I'm  obsessed  with 
computers,  day  and  night,  Even 
though  my  puttering  goes  back  to  the 
oatmeal  box  tuning  coil  and  the  01  A 
tube,  nothing  has  bitten  me  quite  as 
badly  as  the  computer  bug,  So  keep 
up  the  good  work  —  no  construction 
articles  with  lines  running  off  the  page 
to  something  or  other.  If  we  don't 
actually  see  it  hooked  to  something, 
how  can  we  be  sure  where  it  goes? 

Out  here,  we  appreciate  what 
you're  doing,  so  keep  up  the  good 
work. 

"Brad"  Bradford 
East  Brainiree  MA 


/  get   into    enough   trouble   without 
your  encouragement.  -  Wayne. 


OFF  BASE 


] 


We've  been  licensed  for  over  56 
years.  Were  on  a  little  before  that, 
before  licensing  was  required  by  Herb 
Hoover,  who  first  took  charge,  Came 
on  first  on  300  meters  with  spark, 
then  200  meters,  then  1750-2000, 
then  1800  to  2000  and  the  rest  of  the 
bands. 

When  73  first  came  into  business, 
we  were  one  of  your  first  subscribers, 
and  also  wrote  you  a  few  articles. 
Boy,  how  the  years  do  fly  J 

Quit  QST  years  ago  -  no  bnger  a 
real  ham  organ  as  it  was  when 
"Hiram"  ran  it  (and  later  his  imme- 
diate successors},  Present  boys  are 
more  for  business  interests  than  hams. 
Hams  play  2nd  fiddle!  Buy  Q$T  now 
and  then  to  see  if  it's  any  better,  but 
nof  HI! 

Wrote  an  article  a  couple  of  years 
ago  pointing  up  how  a  few  manufac- 
turers such  as  Millen  will  sell  direct  to 
hams  to  promote  building  (I'm  a 
builder  —  always  was).  In  It  I  criti- 
cized those  manufacturers  who  make 
components  and  also  equipment  for 
making  components  hard  for  hams  to 
get  —  so  as  to  force  purchase  of 
equipment.  I  compliment  MilEen  and 
others  who  either  sell  direct  to  hams 
or  promote  components  to  distribu- 
tors (instead  of  blocking  distributors}, 
etc.,  etc. 

QST  refused  to  print  it.  It  would 
have  helped  hams  who  build,  but  QST 
was  more  concerned  about  their  "big 


boy"  advertisers! 

Just   thought  you   might   like   the 
above  facts  for  what  they  are  worth, 

Jim  Grind JeW9QS 
Chesterton  IN 

Jim,    I    wouldn't    have    published 
your  letter  either,  and  not  for  fear  of 
any  advertisers ,  . .  but  because  f  think 
you  are  off  base.  Distributors  got  out 
of  the  parts  business  because  it  was 
not  profitable  . .  .  pure  and  simpfe. 
One  result  of  the  incentive  licensing 
(proposed  by  A8RLAXST   in    7963) 
was   that  not  only  did  ham  growth 
stop   and  over  75%  of  the  sale  of 
eQuipment  stop  for  several  years,  but 
hams  stopped  building,  too.  It  got  so 
Lafayette   was    the   only  place   you 
could  buy  parts  as  several  hundred 
distributors  gave  up  the  ghost.  Parts 
houses  are  back  w  force  now,  bur  are 
more  specialized  .  > .  Godbout,  James, 
SD    Sales,     Optoelectronics,    Bullet, 
Verada,  Poly  Paks,  Meshna,  Tri-Tek, 
Whitehouse  .  . .  etc  —  Wayne. 


THE  NOVICE  CLASS 

I  subscribe  to  both  73  and  OS Tw 
hut  find  your  magazine  to  be  the  best. 
Certainly  I  tend  to  agree  with  your 
political  outlook  as  regards  amateur 
radio  more  often  than  1  do  that  of  the 
ARRL 

I  am  a  new  amateur,  but  with  a 
long  time  interest  in  the  hobby.  I  tried 
once  before  about  twelve  or  fourteen 
years  ago  to  get  a  license  but  was 
unsuccessful.  Now  I  am  the  proud 
holder  of  a  new  Novice  ticket.  This 
leads  me  to  write  the  following 
comment  about  the  Novice  class. 

One  of  the  reasons  that  I  didn't  get 
the  license  earlier  was  that  I  wished  to 
skip  the  restrictions  placed  upon  the 
Novice  (and  CW)  and  go  directly  to 
the  General  class,  but  I  was  a  fairly 
young  and  inexperienced  child  at  the 
time  and  found  everything  involved 
just  too  frustrating  and  just  let  the 
whole  thing  drop.  If  I  had  gone  for 
the  Novice  ticket,  I  could  have  been 
on  the  air  and  gathering  experience, 
instead  of  being  just  more  and  more 
turned  off  by  the  whole  thing. 

In  the  Novice  class  that  I  attended  I 
found  the  same  thing  to  be  still  true. 
There  was  one  small  boy  {how  come 
there  aren't  more  small  girJs?  —  but 
that's  another  problem)  who  was 
having  a  lot  of  difficulty.  He  could 
have  been  coached  and  hand  held 
through  a  Novice  exam,  but  I  am  not 
so  sure  that  he  could  have  been 
coached  enough  to  pass  a  more 
advanced  test,  i  know  that  there  are 
very  young  children  who  manage  to 
pass  Extra  exams,  but  I  am  concerned 
with  the  average  child.  For  these 
children  the  Novice  license  is  ideal, 
and  I  think  that  it  should  be  retained. 
I  am  gfad  to  see  that  -  the  FCC  is 
making  steps  in  the  direction  of  a 
renewable  license  in  this  class. 

I  took  the  Novice  test  because  I 
wanted  to  be  abte  to  operate  while  I 
was     studying     for     the     General 


(Advanced  realty,  but  t  am  trying  not 
to  give  into  hubris).  I  would  have 
taken  the  Technician,  but  six  months 
ago  there  were  no  high  frequency 
privileges  for  this  class.  For  older, 
more  advanced  individuals,  this  seems 
to  me  to  be  a  better  entry  class. 

There  are  many  problems  with 
getting  started  in  amateur  radio,  and  if 
we  want  the  hobby  to  grow  we  should 
systematically  consider  them  along 
with  possible  solutions.  I  just  wanted 
to  air  my  thoughts  on  this  one  aspect 
of  the  problem,  I  am  a  professional 
educator  and  the  learning  aspects  of 
amateur  radio  are  thus  close  to  my 
heart. 

John  Thomas  Berry  WN6NZW 

Pasadena  CA 


OFF  TRACK 


Shortly  after  assembling  my  SB -401 
two  years  ago,  the  transmit- receive 
relay  began  to  stick,  especially  after 
lengthy  transmissions  or  extended 
tune-up  periods.  Measuring  voltage 
across  RL2  revealed  that  voltage  was 
indeed  dropping,  yet  the  relay  just 
wouldn't  quit.  Popping  the  function 
switch  to  spot  would  restore  normal 
operation,  and  running  the  companion 
SB- 200  seemed  to  reduce  the  problem 
almost  completely, 

It  wasn't  until  recently  that  the 
sticky  relay  problem  finally  prompted 
some  real  action.  A  local  Novice 
bought  the  SB -401  and,  after  oper- 
ating CW  for  a  while,  aggravated  the 
situation  so  that  the  relay  wouldn't 
respond  to  the  old  spot  trick.  Replace 
the  relay  was  one  answer,  since  it 
seemed  tike  the  problem  could  be 
residual  magnetism, 

A  call  to  Heath  showed  how  far  off 
the  track  we  were,  Dave  Poplewski 
knew  immediately  what  we  were  up 
against  .  .  ,  and  answered  that  there 
were  two  ways  to  solve  the  problem 
(an  expensive  one  and  a  cheap  one). 
Needtess  to  say,  we  were  most  inter- 
ested in  the  cheap  way  out.  Dave 
explained  that  the  problem  was  soft 
finals  -  finals  that  were  not  soft 
enough  to  affect  output,  but  soft 
enough  to  allow  screen  grid  leakage 
through  RL1  back  to  RL2.  The  best 
cure.  Dave  advised,  was  to  ground  Jug 
7  of  RLT.  That  way  screen  grid 
leakage  can't  reach  the  transm it- 
receive  relay,  RL2.  The  expensive 
cure?  Replace  the  finals, 

Warren  Elly  WA1GUO/1 
Bennington  NH 

One  other  cure  -  learn  how  to  tune 
your  rig. 


I/O  RIP  OFF 


Please  publish  the  following  letter 
in  an  attempt  to  recover  a  stolen 
computer  system  from  my  home  on 
or  about  the  fourth  of  September  of 
this  year. 


The  equipment  taken  is  listed  as 
follows:  (1}  1  Altair  8B0O  consisting 
of  (a)  t  CPU  card,  {b)  6  88-4MCD 
dynamic  memory  cards,  (c)  1  16K 
static  memory  card  (Mikra-D),  {d)  t 
88-OCDD  disc  controller  card  set  {2 
cards),  (e)  2  88  disc  floppy  disc  drives, 
(f)  1  88-PMC  PROM  memory  card 
with  PROM,  ig)  1  88-ACR  cassette 
interface,  <hj  \  88-2SIO  serial  inter 
face  with  both  ports:  (21  1  HP  65 
programmable  calculator;  (3)  camera 
equipment  consisting  of  fa)  1  Honey 
well  Pentax  Spot  matte  II  with  1.4 
lens,  (b)  T  Vivatar  85  205  mm  auto- 
zoom  lens,  (c)  1  Honeywell  450auto- 
strobonar  flash. 

If  anyone  reading  this  letter  has  a 
reason  to  believe  he  has  been  offered 
any  of  this  equipment  or  thinks  he  has 
seen  this  equipment,  please  contact 
your  local  police  authorities  or 
contact  me  at  the  following  address. 

John  W.  Swain 

3687  N.  East  County  Line  Road 

Indianapolis  IN  46236 

[317)-894~7271 

You   waited  too  long  to  write  your 
house  security  program. 


CATCHING  ON 


] 


Your  magazine  and  the  articles  in  it 
have  shown  me  the  close  relationship 
hams  have  wfth  each  other  and  this  is 
what  encouraged  me  more  than  any- 
thing else  to  work  for  my  amateur 
ticket.  Some  of  your  articles  are  stilt  a 
little  deep  for  my  shallow  mindr  but 
I'm  catching  on.  Keep  up  the  good 
work  —  you  have  a  fine  magazine. 

Bill  Raney  WrvSTGS 
Laredo  TX 


THE  GENERAL  GOOD 


This  hint  has  saved  me  a  lot  of 
bother,  and  you  might  find  it  worth 
passing  on  for  the  general  good : 

You  have  finally  decided  that  the 
antenna  halliards  must  be  replaced 
before  they  fall  apart,  and  you  have  a 
length  of  fine  new  rope  for  the  job. 
But  how  to  get  it  through  that  pulley 
at  trie  top  of  the  tower?  The  sheave 
won't  pass  a  knot,  or  even  a  splice.  So 
you  climb  the  tower,  or  tower  it  to 
the  ground.  Neither  one! 

Take  a  four  Inch  length  of  coax, 
RG  58/U  for  small  rope,  or  RG  8/U 
for  thicker  stuff.  Cut  off  and  discard 
all  but  the  braid.  Insert  one  end  of  the 
old  rope  into  one  end  of  the  braid, 
and  an  end  of  the  new  one  into  the 
other.  Pufl  taut,  and  the  harder  you 
pul)r  the  firmer  the  grip  of  the  braid 
on  the  rope  ends.  It  may  be  necessary 
to  wrap  a  few  turns  of  thread  around 
the  leading  end  of  the  braid  to  control 
fraying,  Pull  down  the  free  end  of  the 
old  rope  and  let  the  new  one  follow  it 
through    the    sheave    and    back    to 


Continued  on  page  25 


19 


New  Products 


EICO  DLP-6 

If  you've  been  working  with  digital 
logic  circuits,  you've  probably  already 
discovered  thai  there's  no  really 
simple  way  lo  debug  them.  A t  first 
glance,  this  may  seem  surprising  One 
of  the  nice  features  of  logic  is  chat 
you  don't  generally  know  or  care 
what  the  exact  voltage  level  at  a  test 
point  is  .  .  .  only  if  it's  high  or  low,  a 
togtc  1  or  0,  As  a  matter  of  fact,  a 
cheap  VOM  is  quite  adequate  for 
static  logic,  and  a  dc  scope  is  even 
better.  Since  the  voltages  aren't 
important,  a  circuit  using  an  LED 
which  lights  for  a  1,  and  is  unlit  for  a 
zero,  is  great,  and  for  $20  to  $200, 
depending  on  your  tastes  and  budget, 
you  can  buy  one  of  several  clip-on 
probes  that  will  display  the  logic  level 
on  each  pin  of  a  14-  or  16-pin  DIP, 
The  better  ones  don't  even  need 
power  -  they  locate  and  draw  from 
the  supply  pins  of  the  IC  itself. 

The  problem  is  that  most  of  the 
interesting  logic  circuits  aren't  static  — 
there  are  all  kinds  of  pulses  flying 
around,  and  it's  usually  these  pulses 
that  are  the  important  factors.  Worse 
yet,  they  don't  always  come  at  regular 
time  intervals,  so  you  can't  sync  them 
in  on  an  inexpensive,  repetitive- trace 
scope.  Even  if  you  could,  you  may 
not  be  able  to  see  them.  TTL  logic  can 
respond  to  pulses  that  can't  be  seen 
on  any  but  the  fastest  scopes.  One 
trick  I've  seen  is  to  use  a  triggered 
sweep  scope,  with  the  threshold  set  so 
it  normally  doesn't  sweep*  When  you 
get  a  sweep,  you  still  can't  see  the 
pulse,  but  you  know  something  pulted 
the  trigger  (of  course,  it  could  have 
been  your  wife's  hair  dryer).  Aside 
from  the  obvious  overkill  of  using  a 
$3000  scope  to  check  out  a  handful 
of  20tf  gates,  this  method  is  not  too 
satisfactory.  The  setting  of  the 
threshold  is  tricky,  especially  if  there 
are  other  pulses  around,  and  you  still 
never  see  that  pulse. 

Straight  LED  indicators  are  no 
better.  White  the  response  time  of  an 
LED  is  very  fast,  that  of  your  eyeball 
isn't.  As  it  turns  out,  the  human  eye 
can  see  surprisingly  short  pulses  of 
light,  under  the  right  conditions,  but 
it  has  a  long  retention  time.  This 
means  (hat  in  a  darkroom,  you  may 
see  that  LED  flash  on;  you'll  never  see 
a  lit  LED  f lash  off. 

It  looks  like  what  this  country 
needs  is  a  good  S20  logic  probe  that 
can  see  pulses  of  either  polarity,  as 
well  as  static  levels,  and  display  the 
situation  to  you  in  a  way  that  can't  be 
misunderstood.  The  Elc©  0LP  6  is  an 
LED  probe  that  fills  the  bill.  The  key 
feature  is  a  pulse-stretcher  that  detects 
positive-  or  negative  going  pulses  as 
short  as  50  ns,  and  gives  you  about  a 
half-second  flash  on  a  pulse  LED.  In 
this  respect  it's  similar  to  Ted 
Lincoln's  circuit  173,  Aug.  76,  pg. 
106).  It  also  has  LEDs  lor  both  high 
and  low  static  levels,  which  permit  a 


feature  I  haven't  seen  before  —  it  can 
tell  the  difference  between  an  active 
high  or  low,  and  an  open  circuit.  This 
can  he  really  useful.  As  a  final  touch, 
the  three  LEDs  are  different  colors 
{red,  green  and  ye  How)  P  so  unless 
you're  color  blind,  it's  pretty  hard  not 
to  get  the  message. 

The  DLP-6  comes  in  a  bubble  pack, 
complete  with  a  small  plastic  carrying 
case.  All  parts  mount  on  a  narrow  PC 
board,  which  slips  inside  the  body  of 
the  probe.  Assembly  is  quite  straight- 
forward and  takes  about  an  hour.  The 
instructions  are  no  Heathkit  manual, 
and  there's  one  error  in  one  of  the 
figures,  but  in  genera!  everything  went 
together  as  intended.  Etco  says  to  use 
the  green  LED  for  the  "high"  indi- 
cator, and  red  for  "low."  This  seemed 
backwards  to  me,  so  I  reversed  them. 
The  LEDs  seem  to  be  interchangeable, 
so  use  your  own  color  scheme.  If  you 
make  up  your  mind  before  soldering 
them  in,  you  may  not  burn  them  up 
removing  them  as  I  dNJ!  (LEDs  are 
more  sensitive  to  heat  than  ICs,  and 
these  have  to  mount  absolutely  flush 
with  the  PC  board  or  you  won't  be 
able  to  get  it  into  the  probe  body.  A 
power  cord  comes  out  the  back  of  the 
probe,  and  is  terminated  with  alligator 
dips.  Yes,  Virginia,  the  probe  needs 
external  power.  You  didn't  think  you 
were  going  to  draw  power  from  the 
chip  with  just  the  probe  tip,  did 
you?  J 

In  operation,  just  connect  the  two 
alligator  dtps  to  any  source  of  five 
volt  power  and  ground,  and  you're 
ready  to  start  probing,  The  three  color 
system  is  very  easy  to  read,  and  after  a 
Nttle  practice  you  can  get  quite  a  bit 
of  information  from  those  three 
lights. 


Recently,  J  had  occasion  to  use  the 
DLP-6  to  find  a  bug  in  my  TVT  III 
had  been  trying  for  two  days  to  find  a 
missing  pulse,  before  it  slowly  dawned 
on  me  that  the  pulse  was  so  short  I 
wouldn't  be  able  to  see  it  on  my  scope 
even  when  I  "found"  It.  Using  the 
DLP-6,  it  took  about  fifteen  minutes 
to  find  a  NAND  gate  with  positive 
pulses  in  on  all  inputs,  but  no  negative 
pulse  out  Aha' 

As  a  matter  of  background,  the 
circuit  used  in  the  DLP-6  originally 
appeared  in  Popular  Electronics 
{Richard  P,  Ma  v.  March  '74,  pp. 
33  35 J,  along  with  a  PC  layout,  so 
apparently  both  are  in  the  public 
domain.  Buy  it  or  build  itr  but  try  it; 
you'll  like  it' 

Dr.  Jack  W.  Crenshaw 

1409  Slevins  Gap  Rd. 

HuntsviHe  AL 


THE  KLM  MULT  I -2700 
ALL  MODE  TRANSCEIVER 

With  interest  in  OSCAR  mounting, 
and  SSB  activity  up  on  2  meter  FM,  it 
was  inevitable  that  someone  was  going 
to  come  up  with  a  do  anything/every- 
thing transceiver.  Now.  KLM  has.  It's 
the  new  Multi-2700  .  .  ,  with  OSCAR 
Mode  A,  upper  and  lower  sideband, 
WBFM,  NBFM,  AM  and  CW  all 
stuffed  into  one  28  lb.  package. 

When  KLM  introduced  the  Multi- 
2000  some  years  ago,  it  was  in  a  class 
by  itself.  Then  came  Kenwood's 
TS-700A  and  the  Yaesu  FT-221,  and 
the  VHF  sideband  boom  was  on 
(commercially  speaking).  Bui  no  one 
offered  the  best  of  both  worlds  ...  it 
was  either  a  synthesizer  or  VFO  ... 
no  combinations.  OSCAR  work  still 
required  a  separate  receiver  and  trans- 
mitter, but  SSB  activity  on  the 
satellite  sure  came  up. 

The  next  step  was  to  put  it  all  in 
one  package.  With  Mode  A  in  mind, 
KLfVTs  idea  was  to  synchronize  29 
MHz  receive  with  145  MHz  transmit. 


while  maintaining  a  constant  116.45 
MHz  difference  between  them.  Using 
the  synthesizer  and  VFO  you  can 
work  through  the  satellite  or  monitor 
beacon  signals  at  the  flick  of  a  switch. 
Because  the  Multi  is  a  transceiver, 
however,  the  big  difference  between 
normal  OSCAR  operation  and  using 
the  2700  is  that  you  can't  monitor 
your  relayed  signals  from  the  satellite. 
One  then  has  to  rely  on  the  beacon 
signal  (received  separately  on  the 
synthesizer).  As  long  as  you  can  hear 
the  beacon,  you  can  work  the  sate! 
lite,  KLM  has  left  room  for  Mode  B 
work,  with  a  450  MHz  Converter 
coming  to  fit  into  internal  terminals, 
(50  MHz  converters  are  also  planned.) 

The  Multi-2700.  in  a  word,  is 
loaded  There's  an  8  pole  SSB  filter, 
two  FM  filters,  VXO  and  RIT.  LED 
readout  on  the  synthesizer,  audio 
speech  compression,  ac/dc  power 
supply,  separate  output  and  deviation 
meters  and  VOX.  The  VFO  setup 
features  a  5  to  1  tuning  ratio,  with  the 
inside  knob  going  20  kHz  per  revo- 
lution and  the  oirter  knob  going  100 
kHz. 

All  that  costs  money,  of  course, 
and  the  Mufti's  price  tag  reflects  it. 
But  at  $799.95  KLM's  newest  is  not 
out  of  the  price  class  for  all-mode 
VHF  gear.  At  that  rate  the  OSCAFl 
capability,  hear  your  own  signals 
through  the  sale  Mile  or  not,  is  a 
bonus. 

Operating  the  2700  is  pretty 
simple,  and  with  only  a  vertical  both 
SSB  stations  and  repeaters  could  be 
worked  quite  adequately.  Working 
OSCAR,  however,  takes  a  bit  more 
practice  with  the  VFO  and  synthe- 
sizer. Availability  may  be  an  initial 
problem;  as  we  go  to  press  only  25 
units  have  reached  the  slates,  bui  a 
KLM  spokesman  says  production 
should  be  up  substantially  by  the  time 
you  read  this. 


A  clean  layout  -  with  VOX,  AGC  and  gatn  controh  accessible  through  top  port* 


20 


The  "guts' "  view  —  note  29  MHz  receiver,  upper  left,  and  space  for  p  fug-in  450 
MHz  unit  below. 


NEW  1977  RADIO  SHACK 
CATALOG  No.  276 
NOW  AVAILABLE 

Radio  Shack's  new  1977  Elec- 
tronics Catalog,  featuring  its 
exclusive  line  of  products  for  home 
entertainment,  hobbyists,  CBers  and 
experimenters,  js  now  available  from 
Radio  Shack  stores  and  dealers, 
nationwide. 

The  all-new  164-page  catalog 
includes  100  full-color  pages 
describing  the  company's  complete 
fine  of  products.  Prices  in  the  new 
catalog,  which  marks  Radio  Shack's 
56th  year  in  business,  are  reported  to 
be,  on  the  average,  within  1%  of  the 
company's  average  1975  prices. 

Among  the  new  items  introduced  in 
the  catalog  are:  eight  new  stereo 
FM/AM  receivers,  led  off  by  the 
Realistic  STA-2000  75  Wan  per 
channel  receiver,  the  Optimus  T-100 
Tower  speaker  system,  the  new 
LAB-300  turntable  and  several  new 
stereo  tape  cassette  recorders. 

Radio  Shack  is  also  introducing  an 
all-new  line  of  pocket  calculators 
ranging  in  price  from  $10.95  for  a 
5-function  model,  to  $39.95  for  a 
scientific  slide-rule  calculator. 

Other  items  featured  in  the  catalog 
include:  Realistic- brand  CB  two-way 
radios,  automotive  tape  players, 
portable  radios  and  scanning 
monitors,  Archer  antennas,  Micronta 
test  instruments  and  ArcnerKit  and 
Science  Fair  electronic  and  hobby 
kits. 

In  addition,  the  new  catalog  lists 
hundreds  of  specialized  electronics 
items,  parts  and  accessories,  tools, 
tubes,  semiconductors,  wire  and  cable, 
home  security  products,  intercoms, 
microphones,  timers,  batteries  and  a 
complete  library  of  Radio  Shack's 
own  books  on  electronics  and  related 
subjects. 

The  catalog  also  includes  bonus 
coupons  good  for  a  50%  savings  on 
the  company's  own  Supertape  and 
Realistic  brands  of  tape,  and  a  coupon 
worth  $1,00  on  the  purchase  of  their 
$1.25  book,  All  About  CB  Two-Way 
Radio, 


In  announcing  the  new  catalog, 
Radio  Shack  president  Lewis  Kornfetd 
stated:  "That  great  old  American 
institution,  the  Radio  Shack  catalog, 
has  just  been  published  again,  entirely 
revised,  available  in  all  our  stores,  and 
still  free!  Free  to  you.  To  us  it 
represents  an  investment  over  $3 
million, 

"The  total  printing  comes  to 
2, 1 32,000,000  pages,"  Komfeid 
continued,  "Stretched  end  to  end: 
1,777,777,777  linear  feet  or  336,700 
miles,  or  13.525347  times  around  the 
world  at  the  equator.  The  new  1977 
edition  consumed  3787,5  tons  of 
paper  and  1,222,000  pounds  of  ink. 
These  statistics  are  revealed  to  dis- 
courage our  competition.  And  to  give 
cheer  to  America's  postmen  who 
don't  have  to  deliver  the  catalog  since 
none  are  mailed  —  you'll  have  to  get 
your  copy  at  one  of  our  stores." 


NEW  VIZ  FREQUENCY 

COUNTER  USES  PRECISE 

CRYSTAL-CONTROLLED 

TIMEBASE  FOR 

EXCEPTIONAL  ACCURACY 

VIZ  Manufacturing  Company  has 
introduced  a  frequency  counter  to  its 
growing  fine  of  test  instruments,  The 
WD -752 A  counter  is  designed  for 
making  frequency  measurements 
between  10  Hz  and  60  MHz  in  audio, 
video,  CB,  ham  radio  and  other  com- 
munications  equipment. 

A  unique  feature  of  the  counter  is 
its  1  kHz  audible  sldetone  with 
separate  on-off  volume  control.  The  1 
kHz  tone  is  valuable  in  modulating 
single  sideband  transceivers  for  carrier 
frequency  measurement.  The  counter 
has  a  selectable  input  sensitivity  of 
either  10  or  100  mV;  the  lower 
sensitivity  is  valuable  when  consider- 
able noise  is  present  with  the  signal* 

The  counter  uses  a  carefully 
selected  10,000  MHz  crystal  to  create 
an  extremely  accurate  timebase, 
ensuring  the  accuracy  of  the  10,  100 
and  1000  millisecond  gate  signals  and 
logic  control.  The  measuring  circuit  is 
composed  of  a  si x- state  IC  counter 


which  feeds  into  a  very  bright  readout 
made  up  of  six  0.3"  seven-segment 
LEDs,  The  frequency,  decimal  point, 
and  range  (either  MHz  or  kHz)  are  all 
displayed  automatically.  A  signal  lamp 
indicates  when  the  signal  is  suffi- 
ciently strong  to  be  counted  and 
indicates  when  the  higher  sensitivity 
input  is  required.  An  overflow  lamp 
indicates  a  signal  that  exceeds  1  MHz 
when  using  the  1  second  fixed  gate. 

The  BNC  input  is  compatible  with 
most  standard  broadband  oscilloscope 
probes,  When  making  measurements 
of  transmitter  or  transceiver  AM  fre- 
quencies, the  counter  is  positioned 
near  the  transmitter  and  a  one  meter 
cable  attached  to  the  input  serves  as  a 
pickup  antenna.  The  counter  can  also 
be  attached  directly  to  a  transmitter 
or  transceiver  with  a  directional 
coupler  and  dummy  load. 

The  counter  operates  on  115  V  ± 
10  Vr  50/60  Hz.  The  unit  is  extremely 
compact,  measuring  only  2-5/8"  x 
5-3/4"  x  9-1/4",  and  weighs  only  4 
lbs.  The  dealer  optional  price  is 
$255.00. 

Further  information  on  the 
WD-752A  frequency  counter  is  avail- 
able from  Bob  Llska,  Vl2  Test  Instru- 
ments Group.  VIZ  Mfg.  Co.,  335  E 
Price  St,  Philadelphia  PA  19144, 
(215)-844-2626, 

NATIONAL'S  NEW  VOLTAGE 
REGULATOR  HANDBOOK 

It  would  be  difficult  to  find  a 
handler  guide  to  voltage  regulators 
than  National  Semiconductor's  latest 
release.  The  handbook  is  chock-full  of 
great  circuits,  theory  and  seemingly 
endless  specs  on  not  only  Mational's 
line,  but  comparison  data  on  the 
competition  as  well. 

It  truly  is  a  handbook,  since  the 
opening  pages  cover  power  supply 
design  basics,  transformer  specifica- 
tions, rectifier  circuits,  filtering  and 
load  effects.  But  that's  not  all  Heat 
flow  and  thermal  resistance  theory 
get  their  due  along  with  heat  sink 
design  and  applications. 

At  $3  a  shot  (California  residents 
add  6%  sales  tax)  the  National  Voftage 
Regulator  Handbook  is  a  heck  of  a 
value.  Send  your  check  to  National 
Semiconductor  Corp.,  Marketing  Ser- 
vices Department,  2900  Semiconduc- 
tor Drive,  Santa  Clara  CA  95051. 

Warren  Elly  WA1GUD/1 
Bennington  NH 


THE  SENCORE  F-14 
FIELD  EFFECT  METER 

Like  most  hams  interested  in  con- 
struction and  troubleshooting,  I  have 
become  accustomed  to  having  two 
types  of  meters  to  fill  my  needs.  A 
20k  Ohm  VOM  was  used  for  porta- 
bility, general  testing  and,  most  essen- 
tially, for  current  measurements.  A 
VTVM  was  also  a  must  for  high 
impedance  voltages,  and  with  an 
accessory  probe  for  rf  measurements. 
Redundancy  was  unavoidable  since 
both  types  of  meters  offer  duplicate 
capabilities  in  some  respects,  while 
each  possesses  its  own  uniquely  desir- 


able features. 

A  recent  drive  to  improve  the 
station  test  facilities,  and  a  searching 
review  of  the  latest  products,  led  to 
the  acquisition  of  the  Sencore  F-14 
Field  Effect  Meter,  which  succeeds  in 
obsoJeting  both  of  my  original  meters- 

Of  particular  interest  to  hams  is  the 
fact  that  the  F-14  packs  all  the  desir- 
able features  of  a  VOM  and  VTVM 
into  a  single  unit,  Field  effect  tran^ 
sistors  replace  the  functions  of  the 
traditional  vacuum  tubes,  providing 
better  characteristics  than  the  VTVM, 
without  the  need  for  ac  line  power. 
And,  in  addition  to  7  ranges  of  ac/dc 
volts  and  5  resistance  ranges,  the  F-14 
also  measures  dc  current  in  5  ranges 
from  100  uA  to  1  A  full  scale. 

Special  features  include:  very  high 
input  impedance;  15  megohms 
shunted  by  14  pF  on  dc  volts;  10 
megohms  shunted  by  29  pF  on  ac 
volts.  Ac  volts  provides  a  broad  band- 
width from  10  Hz  to  10  MHz  at  3dB 
points  without  an  accessory  probe. 
The  meter  face  includes  scales  for  ac 
peak  to  peak  voltages,  a  zero  centered, 
plus  and  minus  volts  for  servicing 
contemporary  solid  state  circuitry, 
and  a  mirrored  strip  for  optimum 
readout  accuracy.  Positive  meter  over- 
load and  FET  circuit  protection  is 
incorporated  to  guard  against  incor- 
rect voltage  application. 

The  F-14  instruction  manual  in- 
cludes construction  details  for  some 
simple  adapters  to  further  increase  the 
flexibility  of  the  unit,  such  as  a 
plug- in  shunt  to  extend  dc  current 
measurements  to  10  A,  a  switch  able 
shunt  for  ac  current  ranges  of  1,  3  and 
10  A,  and  the  accurate  measurement 
of  very  small  dc  currents  encountered 
in  transistor,  diode  and  capacitor 
leakage,  in  the  order  of  nanoamps 
{0,001  uA), 

This  little  gem  weighs  in  at  less  than 
3!4  lbs.  with  batteries,  and  occupies 
about  half  the  cubic  space  of  the 
average  VTVM,  with  a  large  4%'*  x  3" 
meter  face.  The  rugged  all  steel  case  is 
vinyl  covered  for  an  added  appearance 
touch,  and  practical  protection.  Bat- 
teries  required  are  standard  types 
available  at  any  drugstore  or  super- 
market, 

On  the  bench,  in  mobile  or  portable 
applications,  anywhere  you  need  to 
use  it,  the  F-14  is  instantly  ready  at  a 
flick  of  the  switch,  with  no  warm-up 
period  for  stabilization.  Oh,  yes!  I 
found  some  industrial  type  solid  state 
meters  in  The  catalogs  offering  similar 
capabilities  —  at  about  twice  the  price 
of  the  F-14, 

General  Description 

Meter:    4Va",    100    uA,    ±2%,    diode 
protected  and  isolated  from  input. 
Multiplier     Resistors:      1%    precision 
type. 

Ohms     Battery:      1.5     V     "C"     cell, 
Eveready  type  1035  or  equiv. 
Power     Supply     Battery:     9     volt, 
Eveready  type  222  or  equiv. 
Weight  (less  batteries):  3%  lbs. 
Dimensions:    5"    W   x    7  3/16"    H    x 
3-1/16"  D. 

Peter  A.  Lovelock  W6AJZ 
Santa  Monica  CA 


21 


The  increased  population 
of  amateur  repeaters 
and  the  resulting  interference 
has  forced  many  repeaters  to 
use  tone  access  systems.  The 
tone  burst  system  is  irritating 
to  users,  and  if  a  station 
drops  out  after  accessing  the 
system,  there  is  no  way  for 
the  system  to  be  re  accessed 
until  the  next  transmission. 
These  factors  led  to  the  unit 
described  in  this  article.  The 
cost  of  reeds  for  a  reed 
encoder  is  prohibitive  for 
most  amateurs  ($1 5  for  a  new 
reed  plus  another  $15  for  the 
encoder),  while  this  complete 
circuit  can  be  constructed  for 
approximately  $10, 

Circuit  Description 

The  unit  (see  Fig.  1 )  is  a 
simple  crystal  controlled 
oscillator1    driving   a    CMOS 


PC  board. 


Go  Tone  for  Ten 


--  simple  subaudible  encoder 


Carson  Haines  Jr,  WB6GON 
SI  12  Sylvan  Ave. 
Oakland  CA  94602 


220 


™J5sP     -T* 


N&50 


C4W 


1   T«fc"»w  ,t  Sv 


- 


>« 


CD402Q 


*¥ 


O  iQX 

47K  tOWZ 


47,F 


our 


»     '     '     *     i     i     i     i 


CD4<I20 


r  i  r  r  i  f  i  i  ■ 

&J2  QU>4  QC  «  CT  04  -V 


470K 
Mi2       rt 


^»K 


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rTh 


>». 


8192 


fifr  7,  Subaudible  tone  encoder. 


22 


divider  with  an  RC  filter  on 
i  he  output.  The  CMOS 
divider  was  selected  so  the 
number  of  components  could 
be  reduced  from  four  7490s 
afid  a  precision  vottage  regu- 
lator to  one  CMOS  divider 
with  a  simple  zener  voltage 
regulator. 

In  the  units  constructed, 
FT243  crystals  were  used.  To 
calculate  the  frequency  of  the 
crystals,  see  the  simple 
below: 

Required     Frequency     x     Divide 
Ratio  =  Crystal  Frequency 
Example:     136.5    Hz    x    8192   = 
1.182  MHz 

There  are  two  divide  ratios  on 
the  board,  8192  and   16384. 


Component  layout. 

If  other  frequency  range 
crystals  are  available,  simply 
bring  out  the  required  divide 
ratio  from  the  IC  and  feed  it 
into  the  filter.  The  crystals 
used  in  the  original  units  were 
the  least  expensive  crystals 
Jan  Crystals  had  listed  in 
their  catalog.  Pick  a  crystal 
frequency  as  close  to  the  cal- 
culated value  as  passible.  In 
our  units  for  1 36,5  Hz  the 
closest  crystal  was  1120  kHz. 
This  yielded  an  error  of  .2 
Hz  when  the  dividing  was 
completed,  and  normal  reed 
decoders  are  approximately 
±1  Hz  wide  minimum.  When 
selecting  a  crystal,  try  to  keep 
the  end  error  to  approxi- 
mately .5  Hz  and  you  should 


Fig,  2  Layout  (bottom  view)  for  subaudible  tone  encoder. 

2N2222 


not  experience  any  problems. 
The  oscillator  is  very  broad 
band  and  crystals  from 
around  100  kHz  to  3  MHz 
should  perform  fine. 

The  dividing  is  done  by  a 
CMOS  divider  and  it  is  avail- 
able from  Godbout  Elec- 
tronics. The  CD  4020  has 
divide  ratios  of  2  through  2"!  4 
(16384)  available  and  if  other 
ranges  of  crystal  oscillator 
frequency  are  used,  it  is 
possible  to  pick  the  divide 
ratio  you  require. 

The  output  circuit  is  a 
simple  RC  filter2  which  takes 
the  square  waves  on  the 
output  and  makes  them  into 
a  triangular  waveform.  The 
potentiometer  in  the  output 
is  used  to  set  the  output  level, 
and  the  resistor  value  for  the 


series  resistor  should  be 
selected  for  the  impedance 
into  which  you  are  inserting 
tone. 

Construction 

The  unit  can  be  con- 
structed using  any  means 
available,  The  original  units 
were  constructed  on  PC 
boards  and  a  full  size  layout 
is  included  (Fig.  2).  Parts 
value  is  not  critical,  so  select 
parts  you  have  on  hand  that 
are  near  to  the  values  listed 
on  the  schematic.  The  zener 
can  be  between  6  and  9  volts 
since  the  CD  4020  will  run  on 
any  voltage  between  5  and  15 
volts. 

Operation 

Connect  the  unit  to  a 
source  of  12  volts  that  is 
turned  on  when  the  trans- 
mitter comes  on  or  let  the 
unit  run  all  the  time  (only  10 
mA  is  required).  Connect  the 
audio  and  you  are  ready  to 
go. 

I  will  be  happy  to  answer 
any  questions  you  may  have 
regarding  this  unit,  but  please 
SASE  or  no  answer.  ■ 

References 

1  Ham  Radio,  June,  1972,  page 
11,  "Five  Band  Communications 
Receiver/  M.  A.  Chapman 
K6SDX. 

2  73  Magazine,  April,  1974, 
"Rock  Solid  Subaudible  Tone 
Generator/'  Paul  H.  Wiese 
WA8VDC 

Parts  Available  From 

Jan  Crystals 
2400  Crystal  Drive 
Ft.  Myers  FL  33901 

Godbout  Electronics 
Box  2355 

Oakland  Airport   CA  94614 


7*35pF 


R  OUT 


BOTTOM  VIEW 


23 


state 


igital 


ran 


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m  access  memory  $ 


SSTV  Scan  Converter 


All  solid  state  Random  Access 

(Memory. 

Slow-to-fast  and  fast-to-slow 
conversion  capability. 

SSTV  picture  display  on  any  stand- 
ard CCTV  monitor. 

Frame  freeze  from  any  standard 
CCTV  camera,  broadcast  video  or 
video  tape  source. 

Permanent  picture  storage. 

Automatic  or  manual  TV  frame 
snatch* 

Internal  grey  scale  generator  pre- 
cision adjustment  standard. 

Capable  of  real  time  display  of 
digitally  processed  fast  scan  video. 


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Slow -to- fast  conversion  capabili 
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the  fast-to-slow  conversion  enabi 

u  id  use  standard  test  scan  video 
(such  as  CCTV  or  television  receiver) 
as  a  source  for  SSTV  transmission. 

Operation  is  easy  to  understand,  sim- 
ple to  work-  If  you  can  operate  a 
mera  and  adjust  a  TV  set,  you  can 
operate  the  new  Robot  Model  400 
SSTV  Scan  Converter 

Our  new  price  is  really  a  break- 
through! Now  you  can  get  into  the 
fast  growing  SSTV  activity  for  ji 
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For  the  complete  story  on  our  new 
Model  400  all  solid  state-digital-RAM 
Scan  Converter,  write  or  call  today 
for  our  new  broehure. 


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ROBOT  RESEARCH.  INC- 

7591  Convoy  Court 

San  Diego.  California  92111 

Phon*  714  279  9430 


■  Please  send  me  complete  information  on  your 
new  Solid  State  SSTV  Scan  Converter, 
I  Hame 

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from  page  19 

ground  The  braid  runs  freely  through 
the  sheave  and  the  job  is  done. 

L  Colin  Curtis  VE7BMK 
Kamloops,  B.C. 

You  kind  of  coax  the  rope  through 
thepulfey,  eh? 


ADAPTOR  PERISH 


In  your  I/O  editorial  in  the  Oct,  76 
issue  of  73,  you  wanted  reader 
response  to  the  content  of  73.  Here's 
my  2  cents  I 

I  have  at  one  time  or  another 
subscribed  to  just  about  every  ham 
magazhe  (yes,  even  QST),  I  presently 
subscribe  to  73  and  Ham  Radio, 

I  have  heard  some  OTs  say  that 
hams  don't  build  anymore.  They're 
wrong!  There  is  more  building  going 
on  now  than  ever  before  in  ham 
history.  True,  we  don't  build  receivers 
and  transmitters  like  our  grandfathers 
did,  but  then  why  should  we?  We  can 
buy  an  excellent  transceiver  for  a 
price  for  which  tt  couldn't  be  built. 
It's  downright  stupid  to  build  a  re 
ceiver  for  $200  when  you  can  buy  it 
for  $100.  But  I'm  getting  off  the 
track.  Suffice  \t  to  say  that  73  is 
geared  toward  the  builder,  QST  is  not < 
f  believe  that  QST  is  trying  to  please 
every  ham  all  the  time.  If  you  want  to 
read  16  pages  of  contest  results,  then 
by  all  means  subscribe  to  QST.  Ham 
Radio t  on  the  other  hand  is  an  excel- 
lent  magazine  for  the  builder.  But, 
and  a  big  but,  HR  is  not  geared 
toward  the  average  ham,  The  steel- 
worker  or  autoworker  who  pots  in  a 
hard  8  every  day  doesn't  have  time  or 
patience  to  get  into  anything  too 
deeply,  tf  I  have  some  knowledge  on  a 
topic,  I  can  usually  follow  an  HR 
article.  But  when  I'm  completely 
ignorant  about  something,  I  look  it  up 
in  73,  That  about  says  it, 

A  few  words  about  the  I/O  section 
of  73: 

I  think  along  with  myself,  most 
experimenters  are  baffled  by  all  the 
I/O  articles  and  ads.  There's  a  lot  of 
stuff  for  sale,  but  we  don't  know  what 
to  do  with  it. 

At  first,  my  opinion  was  that  I/O 
material  dfdn't  belong  in  a  ham  radio 
magazine.  Maybe  it  does  or  doesn't, 
but  let's  go  back  about  6  years  ago. 
Back  in  1970,  something  called  TTL 
ICs  were  being  advertised  here  and 
there  in  all  the  mags.  We  wondered 
what  they  were  good  for  and  why 
computer  surplus  should  be  in  a  ham 


Lhat  <      si 

magazine  in  the  first  place.  Well,  here 
we  are  just  six  years  later  and  we  can't 
live  without  the  damn  things.  ICs  do 
things  cheaper,  quicker  and  easier 
than  any  other  means.  Tney  do  things 
that  couldn't  practically  be  done  any 
other  way.  Sure,  I  struggled  for  a  few 
years  buying  ICs  I  didn't  need,  making 
mistakes  fl  still  make  them,  hut  not  as 
often),  and  building  projects  that 
never  worked.  We  all  \^ave» 

The  point  is  this:  Right  now,  I  can't 
see  a  microprocessor  in  my  future,  but 
six  years  ago  I  didn't  see  why  anyone 
needed  a  frequency  counter,  Boyf 
how  wrong  we  can  be.  Wayne,  I  want 
you  to  know  that  even  though  I  have 
been  in  electronics  for  15  years,  I  am 
struggling  through  the  I/O  articles.  I 
have  to  read  them  2  or  3  times  and 
they  still  don't  make  sense  to  me 
sometimes,  I'm  learning,  not  much, 
and  not  fast,  but  I'm  learning.  Keep 
Cramming  that  Stuff  down  our  throats 
whether  we  say  we  like  it  or  not.  If 
you  don't,  who  will?  Certainly  not 
QST,  HR  is  already  over  most  of  us. 
Don't  give  us  a  magazine  full  of  CB 
construction  projects,  because  six 
years  from  now  we'll  wake  up  and 
find  that  the  world  has  passed  us  by.  I 
don't  understand  most  of  the  I/O 
articles,  but  someday  I  will.  At  orm 
time  I  didn't  know  the  code.  Now  I 
do.  That's  life.  To  surwe  you  have  to 
adapt  or  you  perish.  I'll  bet  my 
grandfather  had  just  as  much  trouble 
understanding  a  crystal  detector  as  I 
have  understanding  a  PROM.  It  didn't 
stop  him  and  it  won't  stop  me.  Keep 
printing  the  I/O  stuff  and  I'll  keep 
Struggling  with  it  Stop  printing  it  and 
well  all  be  crushed  in  modern  tech- 
no  logy. 

Paul  A  Dujmich  WA3TLD 
McKeesport  PA 

Ok,  ok  -  HI  print  it,  M  print  it.  - 
Wayne. 


NOT  PROPER 


Several  recent  events  have 
prompted  me  10  write  this  letter.  It 
concerns  operation  on  two  repeaters 
in  Dallas  on  T47.36  and  147,39.  Some 
Of  the  operation  I  have  witnessed  on 
these  two  frequencies  I  do  not  believe 
to  be  in  the  spirit  of  amateur  radio, 
and  responsible  operators  in  the  Dallas 
area  need  to  take  note. 

The  repeater  on  147,36  is  listed  in 
repeater  directories  as  OPEN.  Several 
of  the  group's  members  have  person- 
ally told  me  that  rt  was  OPEN.  Re 
cent  I  y.    as    I    was  calling  a  friend  of 


mine  on  .36  fmy  friend  is  a  member 
of  the  group).  I  was  asked  to  leave  the 
frequency  at  once  by  a  ham  who 
heard  my  call.  He  said  that  he  person  - 
ally  did  not  like  me  (I  do  not  even 
know  the  man),  and  that  anyone  with 
intelligence  knew  that  the  repeater 
was  CLOSED. 

The  repeater  on  147.39  is  a  closed, 
private  repeater.  This  group  seems  to 
be  unable  to  tactfully  get  that  point 
across.  When  I  first  got  my  synthe- 
sized rig,  I  did  not  realize  that  closed 
repeaters  existed.  I  keyed  up  on  .39, 
gave  my  cat  I,  and  asked  if  anyone 
were  around.  My  call  was  answered  by 
a  ham  who  said  that  it  was  a  closed 
repeater  and  that  outsiders  were  not 
allowed  on  frequency. 

I  believe  that  such  operation  is  not 
proper  in  amateur  radio,  and  that  it 
can  be  greatly  detrimental  to  our 
hobby.  Hams  who  are  concerned 
about  keeping  amateur  radio  as  it  was 
meant  to  be,  should  take  a  close  took 
at  these  problems  and  others  like 
them. 

Blaine  Hamriqk  WB5LSJ/WR5AKL 

DFW  Airport  TX 


NASTY  WARNING 


Regarding  the  interesting  article 
"Have  You  Used  a  Triac  Yet?**  pub- 
lished in  73  Magazine  for  October 
1976  at  page  76:  I  think  a  warning 
might  be  in  order. 

If  a  high  voltage  transformer  were 
used  as  shown  on  page  77  with  the 
resistor/capacitor  across  the  triac,  a 
person  believing  the  triac  "relay"'  to 
be  open,  anti  working  on  the  power 
supply,  might  get  a  nasty  shock, 
especially  if  the  capacitor  were  larger 
than  that  shown, 

I  continue  to  enjoy  73  very  much  — 
keep  up  the  good  work. 

Bill  Allen  WiLU 
Providence  Rl 

A  little  shock  might  be  good  for  some 
of  these  five  volt  TTL  kids, 


COMM-ED 


n 


I  noted  the  comments  about 
Trigger  Electronics.  Let  us  not  forget 
another  company  known  as  Dycomrn, 
or  Dynamic  Communications,  Inc.  of 
Florida. 

Wore  than  two  years  ago,  after  a 
phone  conversation  wrth  Jim  Penny,  I 
ordered  a  front  end  crystal  filter  for 
my  81-21  repeater  in  Whitmore  Lake. 
Upon  arrival,  I  was  astounded  at  its 
physical  construction,  being  in  a  non- 
rf-tight  minibox.  Checks  using  profes- 
sional Hewlett-Packard  and  Singer  test 
equipment  showed  that  It  did  not 
provide  the  B  dB  gain  and  sharp 
selectivity  claimed,  but  in  fact  pro- 
vided considerable  loss  with  multiple 
response  (passed  more  than  one  fre- 
quency}. So  much  for  S75.  I  sent  the 
unit  back  and  asked  for  one  that 
worked  or  a  refund,  Months  went  by 


and  no  answer;  finally,  another  phone 
call,  and  I  explained  the  problem.  Still 
no  refund  or  unit.  Now,  more  than 
two  years  has  passed,  and  I  have  never 
received  the  unit  or  a  refund.  Inso- 
much as  the  repeater  was  moved  to  a 
nearby  town  and  the  equipment  has 
changed,  I  have  no  need  for  a  new 
unit.  But  my  creditors  sure  could  use 
the  $75! 

I  also  had  a  lot  of  problems  with 
the  various  amplifiers  they  sold,  too! 

Henry  Ruh  WB8HE E 
Whit  more  Lake  Ml 


MORE  20777 


After  reading  "Belt  Tightening"  by 
Donald  Chester  K4KYV/1  in  the  July 
issue  of  73,  I  agree  very  much  with 
him  regarding  AM  and  NBFM  usage. 
These  are  about  the  cheapest  means  a 
ham  has  at  his  disposition  to  get  on 
the  air  on  voice  on  HF  Let  us  keep  in 
mind  that  not  all  of  us  can  afford  to 
throw  S6G0  on  an  SSB  set.  Besides, 
Quite  a  number  of  foreign  hams  still 
use  AM  phone. 

On  one  pomt  I  heartily  agree  with 
Docket  20777.  I'd  love  to  have  back 
A-2H  T-5,  MCW  on  the  HF  bands. 

Benjamin  Lam  boy  KP4CA 
San  Juan,  P.R. 


ANGER  TRIGGERED 


Just  a  word  of  sympathy  for 
Horace  WA4CUD  and  Larry 
WA4MJAr  along  with  the  many  others 
JJshot  down"  by  "the  Trigger  man/' 

It  seems  to  me  we  can  do  nothing 
with  this  company  as  individuals. 
Perhaps  you,  or  some  of  our  "ham" 
friends,  could  come  up  with  some 
thing  we  coutd  do  coUectively.  Thts 
company  is  "in  to  me"  to  the  tune  of 
$80,  and  I  do  not  like  the  music  they 
play, 

Have  tried  the  BBB  Ino  luck),  and 
am  going  to  the  Attorney  General  of 
New  Mexico.  Also  have  a  file  wrth  the 
U,S,  Postal  Service. 

Any  other  ideas  would  be  appre- 
ciated. This  company  must  be 
stopped. 

Raymond  E.  Boshart  WB5ROP 

Box  1041  (7T2^ivy) 

Truth  or  Consequences  NM  87901 

Trigger    may  soon   be  sent  out   to 

oasmre     -     or    eise    stuffed    and 
mounted. 


LEARNING  A  LOT 


Just  a  short  note  to  encourage  you 
to  keep  printing  everything  about 
computers  you  can  get  your  mitts  on 
in  73,  At  first  it  was  all  a  mystery  to 
me  and  I  wondered  what  \  was  getting 
in  my  magazine,  but  once  again  {last 
time  was  2  FM)  I  trusted  you  and,  as  a 


25 


direct  result  of  73.  I  now  eat,  sleep 
and  breathe  computers,  I  am  slowly 
stashing  pennies,  but  it  will  be  at  least 
a  year  before  I  can  assemble  a  system 
so  I  will  have  to  read,  team  and  dream 
in  the  meantime.  Please  send  me  a 
year's  subscnpnon  to  Kilobyte  and 
bill  me  before  \  change  my  mind,  t  am 
sure  most  of  it  wilt  be  above  mef  but 
like  73,  when  my  interests  change  or  I 
become  more  knowledgeable,  I  would 
like  to  have  the  back  issues  to  look 
through.  I  am  in  the  electronic 
security  business  and  will  have  a  few 
articles  forthcoming  soon,  I  wish  I 
couJd  trade  alarm  stuff  for  computer 
stuff.  Guess  I'll  have  to  use  the  money 
substitute  being  eroded  by  the  govern- 
ment in  the  meantime  —  convert  my 
alarm  talent  into  a  fascimile  of  a 
federal  reserve  note  and  later  swap  the 
note  to  someone  for  computer  stuff. 
The  government  is  trying  to  protect 
too  many  people.  I'm  tired  of  them 
trying  to  protect  me.  I  have  been 
buying  kerosene  In  plastic  storage 
bottles  (government  issue}  for  many 
years,  Now  it  is  illegal  for  me  to 
purchase  or  store  it  in  anything  except 
metal.  The  government  is  protecting 
me. 

Another  subject  . . .  The  secrecy  of 
communications  act.  Several  of  my 
customers  have  silent  holdup  alarms  in 
stores,  banks,  etc.  These  alarms  call 
the  police  silently  when  they  have  a 
problem.  Last  week  two  of  these 
alarms  were  tripped.  I  heard  the  call 
on  the  police  monitor.  Within  5 
minutes  my  customer  was  on  the 
phone  wanting  to  know  why  the  local 
newspaper  had  called  wanting  to 
know  if  they  had  been  held  up.  This 
seems  to  me  to  be  in  violation  of  the 
act.  My  customer's  life  would  have 
been  in  jeopardy  if  there  was  in  fact  a 
holdup  taking  place  when  the  news- 
paper called,  If  the  holdup  man  had 
answered  the  phone,  I  probably  would 
have  lost  a  customer  and  friend.  The 
paper's  employees  sink  hundreds  of 
dollars  into  police  monitoring  equip 
ment  in  their  offices  and  cars  to  assure 
that  they  will  be  instantly  aware  of 
crimes  and  traffic  accidents  that  are 
happening  and  be  able  to  rush  a 
photographer  and  reporter  out.  Nuff 
said.  Thanks,  Wayne;  l*m  really 
learning  a  lot  from  73.  Its  almost  like 
an  inexpensive  and  highly  entertaining 
college  course.  Especially  liked  the 
articles  about  BASIC  in  the  October 
(1}  issue.  All  the  I/O  editors  are  great 
If  I  can  help  in  any  way  please  feel 
free  as  always . .  . 

Steve  Uhng  WA3SWS 

Ellicott  City  MD 


THE  QRP  CHAMP 


KSJRN's  QRP  transmitter  ("QRP 
Fun  on  40  and  80."  October  f76) 
works  like  a  champ.  It  was  up  and 
running  into  a  random  long  wire  iwo 
days  after  the  magazine  was  received. 
My  first  home-built  transmitter,  12 
contacts  so  far  in  four  days  on  mostly 
80  meters  ,,,VA(  DE,  CT,  and  a  599 


from  MA.  On  40,  one  contact  in  TN 
and  IN  albeit  poor  due  to  the  fre- 
quency of  7143.5  fighting  it  out  with 
Radio  Moscow  on  7150,  I'm  waiting 
for  my  General  and  I  took  forward  to 
moving  outside  of  the  GRM-loaded 
Novice  bands. 

Thomas  R,  Sundstrom  WB2AYA 

Willtngboro  NJ 


GOOD  BUY! 


Compliments.  I  have  read  many 
professional  and  hobby  magazines. 
and  I  must  admit  73  would  be  a  great 
buy  at  twice  the  price.  Each  issue  has 
lots  of  meat  in  it  for  many  interestS- 
Keep  up  the  1/0  section.  I'm  not  into 
computers  but  I  know  I  will  be 
sometime  in  the  future. 

Kent  H.  Gibb  VE6BAF 
Edmonton,  Alberta 

7"w/ee  the  price  .  .  .  hmmmm? 


BEST  IN  THE  WORLD? 

My  subject  is  Atlas  Radio  Com- 
pany, beaded  up  by  Herb  Johnson  and 
his  boys.  I  bought  an  Atlas  21  OX  and 
had  trouble  with  it;  I  sent  it 
back  and  then  it  developed  more 
troubles.  One  day  1  wrote  a  letter  to 
Herb  Johnson  and  explained  the 
troubles.  About  two  weeks  later  the 
UPS  had  a  package  for  me  from  Atlas 
Radio.  Yep,  you  guessed  it;  it  was  a 
brand  new  Atlas  21  OX,  and  as  soon  as 
I  got  the  chance,  I  tried  it  out.  It  was 
hotter  than  a  firecracker  and  some  of 
the  QSOs  I  had  were  as  strong  as  a 
base  station.  You  see,  I  am  trying  to 
get  Bicentennial  WAS  from  a  car,  and 
that  is  quite  difficult  with  a  wet 
noodle  for  an  antenna  and  just  100 
Watts  output.  I  believe  that  there  is  not 
any  other  ham  radio  manufacturer 
who  would  do  what  Herb  Johnson 
did,  and  1  believe  that  Atlas  Radio  is 
the  best  ham  radio  company  in  the 
world. 

Russell  "Bud"  Holderbaum,  Jr, 

W3AEZ/W4JIQ 
Gaithersburg  MD  20760 


[ 


TRUTH  OR  CONSEQUENCES 


Thanks  for  the  latest  73  addition, 
the  hard  copy  reader  service  card. 

Keep  up  the  IC  projects.  I  built  the 
H  R-212  on  page  66  of  the  May  *76  73 
mag.  The  article  says  to  scan  6  chan 
nets,  but  without  any  mods  using  0 
for  8,  up  to  eight  channels  can  be 
scanned.  Also,  by  adding  an  AND 
gate,  ten  channels  can  be  scanned. 
Works  FB.  Qh!  By  the  way;  would 
like  to  see  a  small  article  on  how  to 
make  the  HR-212  hang  in  there 
(delayed  scan)  on  active  channels. 
Also  a  source  for  printed  circuits  to  be 
used  with  the  articles! 


I  see  for  the  last  2  3  months  ads 
missing  from  Altaj  Electronics,  Dallas. 
I  ordered  their  King  clock  and  only 
after  4-5  weeks  delay  and  two  tele- 
phone calls,  was  able  to  get  delivery. 
But  since  then,  I  have  done  business 
with  them  and  have  gotten  prompt, 
courteous  service.  James  Electronics  is 
another  story-  They  have  same  day 
service.  So  far  I've  placed  2  or  3 
orders  with  them  and  have  gotten 
them  back  (including  postal  time] 
within  six  days,  FB! 

How  about  mentioning  the  Fox 
Tango  Newsletter  put  out  by  The 
International  Fox  Tango  Dub,  Milton 
Lower*  WA2AOQ/4,  248  Lake  Dora 
Drive,  W.  Palm  Beach,  Fla,  33411  at 
$5  per  year  (10  issues}.  Its  sole  pur- 
pose is  the  exchange  of  info,  mods, 
etc.,  for  Yaesu  owners  —  a  terrific 
letter.  Well,  that's  it  for  now, 

Tom  Gundlach  WB5JDU 
Truth  or  Consequences  NM 


About  your  article  "QRP  Fun  on 
40  and  80"  (Oct.  70)  by  Si  Dunn 
K5JRN<  GREAT!  I  thought  that  I  had 
to  buy  alt  of  the  old  radio  mags  10 
find  this  kind  of  make-use-of-your- 
junk-boK  gear.  Hope  to  see  more  in 
the  future.  This  type  of  article  makes 
ham  radio  a  challenge. 

Terry  D.  Wright 

WB8UPO/ADM8UPO 

Piqua  OH 


MORE  OF  THE  SAME 

The  article  by  Gabriel  F.  Gargiulo 
{October,  pg.  128)  was  the  best  on 
programming  in  this  issue,  I  thought, 
\t  was  very  clear  and  instructive.  Also, 
your  I/O  editorial  points  out  the 
computers  potential.  Let's  have  more 
of  the  same. 

Ken  McGinnis 
San  Mateo  CA  94401 


PLAIN  ENGLISH 


I  wish  73  Magazine  would  (for 
once)  show  a  construction  article 
which  was  written  in  plain  English! 
Terms  like  TTLr  PLL,  coil  phasing  {in 
one  article  it  said  'The  coils  must  be 
properly  phased  so  the  circuit  will 
oscillate,"  but  never  mentioned  what 
phasing  means  or  how  to  do  it}.  %A, 
etc.,  etc.,  make  the  average  Novice's 
(or  at  least  my)  head  spirt 

You  should  put  one  article  in  each 
month's  issue  designed  especially  for 
Novices  {simple  and  educational)*  I, 
for  one,  would  like  to  design  my  own 
circuits  for  different  projects,  but 
can't  because  of  lack  of  knowledge. 
These  articles  would  help  people  learn 
theory  and  at  the  same  time  show 
them  some  sort  of  practical  use' 

L  and  C  circuits  always  give  me 


trouble.  Figuring  the  proper  value  of 
L  and  C  for  different  frequencies  is 
murder  when  you're  only  an  8th 
grader  {soon  to  be  9th  grader). 

I  hope  other  Novices  who  see  this 
(if  you  print  it)  will  support  this  idea 
or  improve  on  it. 

John  Halliwell 
Hampton  TN 

P,S.  1  have  5-9  weeks  to  go  before  I 
get  my  Novice  license.  I  love  your 
magazine.  Keep  it  up, 
P.P,S.  I  want  to  mention  that  Opto- 
electronics h  a  great  dealer.  Their 
service  was  fast  and  their  electronic 
clocks  work  great! 


TEST  PILOTS  ONLY 

Nearly  every  issue  contains  sub- 
scription offers  for  expanding  73.  I 
would  like  to  propose  another  way  in 
which  new  blood  can  be  brought  into 
the  fold.  Why  not  have  a  WN  section 
similar  to  the  I/O  section  that  will 
teach  us  neophytes  the  basics  of  build- 
ing the  kinds  of  ideas  that  the  more 
advanced  hams  submit? 

After  people  see  that  top-notch 
authors  are  penning  stuff  they  can 
read,  they'll  run  out  and  hopefully  get 
a  life's  subscription, 

I  would  also  like  to  see  an  article  to 
review  2  meter  operations  and  a  few 
on  uP  fundamentals, 

James  I/Vessels,  Jr, 
Louisville  KY 

Sure,  James,  i'd  love  to  have  more 
articles  on  fundamentals  for  Novices, 
but  fife  subscriptions  are  going  to  be 
permitted  only  to  amateurs  over  73 
years  oid  who  are  full  time  test  pi  fats. 
Some  readers  think  we've  already  run 
enough  2m  operations  articles,  hut 
there  sure  is  a  thirst  for  uP  material 
—  Wayne. 


ANOTHER  CHARTER 


I  was  unable  to  give  you  my  sub- 
scription to  Kilobyte  at  the  computer 
convention  this  past  weekend. 

After  seeing  how  well  you  started 
Byte  Magazine  out,  t  am  sure  your 
latest  venture  will  be  as  good  or 
better. 

Please  accept  my  subscription  to 
Kilobyte  for  a  three  year  charter 
membership.  Enclosed  is  my  check  for 
S25.O0. 

Carl  G.  von  Loewenfeldt 
Alexandria  VA 


KING  AND  QUEEN 


Just  a  few  lines  to  let  you  know 
that  Uoyd  Corvin  W6KG  and  Iris 
Gotvin  W6DOD  have  returned  to  Cali- 
fornia, via  Australia.  Western  Samoa. 
American  Samoa  and  Hawaii,  after  a 

Continued  on  page  39 


26 


Compatible  with  all  sub-audible  tone  systems  such  as:  Private  Line, 
Channel  Guard,  Quiet  Channel,  etc. 

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and  most  portable  units 

•  Field  replaceable,  plug-in,  frequency  determining  elements 

•  Excellent  frequency  accuracy  and  temperature  stability 

•  Output  level  adjustment  potentiometer 

•  Low  distortion  sinewave  output 

•  Available  in  all  EIA  tone  frequencies,  67.0  Hz-203.5  Hz 
Complete  immunity  to  RF 

everse  polarity  protection  built-in 


$29.95  each 

A/ired  and  tested,  complete  with 
<-1  element 


communication/  specioJi/ls 

P.  O.  BOX  153 
BREA,  CALIFORNIA  92621 

{714J  998-3021 


K-1  FIELD  REPLACEABLE, 
PLUG-IN,  FREQUENCY 
DETERMINING  ELEMENTS 

$3.00  each 


Complete  five  band  dual  conversion  amateur  communications  receiver. 


I  am  sure  many  radio  ama- 
teurs who  have  home 
brew  rigs  would  love  to  have 
a  matching  receiver.  Deciding 
to  do  something  positive 
about  this  emptiness  in  the 
shack,  1  came  up  with  a  plan 
that   made    the    home    brew 


receiver    not    only    a    possi- 
bility, but  a  reality. 

The  plan  centered  on  re- 
ducing the  complexity  and 
time  of  construction  dramati- 
cally by  using  a  drugstore 
transistor  AM  broadcast  radio 
set     as     the    main    building 


block.  Even  if  you  never  start 
to  build  this  receiver,  I  am 
sure  that  you  will  find  it 
comforting  to  know  that  if  it 
ever  became  necessary,  you 
could  do  it. 

This  receiver,  being  a  dual 
conversion     type,     has     two 


World's  Simplest 
Five  Band  Receiver? 


-  -  using  an  AM  transistor  radio 


Warner  F.  S torts  K3QKO 
5122  Alberta  Ave. 
Baltimore  MD  21236 


local  oscillators  (LO)  and  two 
I  nter mediate  frequency 
amplifiers  (IF).  In  this  circuit 
we  have  to  make  our  own  HF 
LO,  while  both  IF  amplifiers 
and  the  MF  LO  are  parts  of 
the  AM  broadcast  set. 

We  also  have  to  make  six 
other  circuits  to  support  our 
BC  set  to  make  certain  that 
our  project  winds  up  a  real 
communication  receiver. 
These  are  the  HF  radio  fre- 
quency amplifier,  1  MHz 
amplifier,  beat  frequency 
oscillator  (BFO),  S-meter, 
crystal  filter,  and  automatic 
noise  limiter  (ANL), 

When  all  the  circuits  are 
working  together,  their  opera- 
tion is  spectacular  for  such  a 
simple  design.  When  the  rf 
gain  control  is  two  thirds  up, 
a  0.2  microvolt  7.1  MHz 
signal  at  the  antenna  con- 
nector will  read  S9.  The  re- 
ceiver noise  is  too  low  under 
these  conditions  for  me  to 
make  a  measurement  with  the 
simple  equipment  available  to 
me. 

All  I  can  say  about  it  is 
that  I  could  hear  only  signal 
in  the  phones,  and  I  just 
finished  working  F6ARC  on 
40  meters  with  no  trouble  at 
all.  Any  dual  conversion 
birdies  are  less  than  S2  and 
located  so  they  are  no  bother. 

Drift  and  broadcast  station 
feedthrough  is  nil.  Each  of 
the  five  bands  can  be  selected 
by  a  Front  panel  control  and 
is  0.9  MHz  wide.  The  6  dB 
down  bandwidth  signal  selec- 
tivity is  300  Hz  with  the 
phase  control  in  the  CW  posi- 
tion, and  1.2  kHz  in  the  SSB 
position.  It  is  powered  by  a  9 
V  battery  and  the  current 
drain  is  30  mA* 

Circuit  Description 

The  transistor  AM  broad- 
cast set  just  keeps  on  doing 
what  it  did  before  we  bolted 
it  to  the  front  panel  — 
changing  .55  MHz  to  1,6  MHz 
rf  to  sound  at  the  speaker  or 
phones  —  so  there  is  no  need 
to  describe  it  any  further. 
Fig.  1  shows  how  it  works  in 
our  receiver  and  is  supported 
by  the  outboard  circuits. 
These    will    be    described    in 


28 


detail  because  each  is  unique 
in  this  receiver, 

Starting  from  the  antenna 
connector,  Fig.  2,  the  band- 
switch,  S1,  selects  one  of  the 
rf  transformers,  T1-T5.  They 
are  broadband-tuned  to  the 
center  of  the  desired  fre- 
quency range.  Therefore,  all 
the  signals  in  the  frequency 
range  selected  appear  at  the 
gate  of  rf  amplifier  Q1.  Here 
they  are  amplified  as  much  as 
possible  without  adding  noise 
to  the  output.  By  using  a  low 
noise  MOSFET  for  this  ampli- 
fier t  the  receiver  signal-to- 
noise  ratio  is  greatly  im- 
proved. 

To  prove  this  point  with- 
out a  lot  of  rotten  math,  it  is 
logical  that  if  the  rf  signal  is 
made  greater,  the  following 
gain  controls  will  have  to  be 
turned  down  to  yield  the 
same  output  that  was  present 
before  amplification.  If  noise 
was  not  added  in  the  amplify- 
ing process,  all  the  frying 
sounds  generated  by  these 
turned  down  stages  will  be 
much  less. 

The  output  of  the  rf 
amplifier  is  inductive  coupled 
to  the  gate  coif  of  the  con- 
verter transformer,  T6-T10, 
and  selected  by  the  band- 
switch,  which,  also  through 
other  poles,  applies  this  signal 
to  gate  1  of  the  HF  converter 
Q2  (along  with  the  HF  LO 
output  to  gate  2). 


V 


A  IN  re  N  N  A 


RF 

AMPLIFIER 

Ql 


EFO 

1/2  MHi 


CRYSTAL 
FILTER- 

ANL 
06.07 


CONVERTER 
0£ 


J  MHz 

l-F  AMPLIFIER 

05 


T     SAND 
V)    SWITCH 

LO  FREQUENCY 

MULTIPLIER 
04 

m — 

HF  LO 
03 

PICK-UP 
COfL 


n 


S  METER 
09,010 


AM 

TRANSISTOR 
BROADCAST 
RECEJVER 


PHONES 


RF 

GAIN 
RI6 


Fig.  7.  Block  diagram. 


The  HF  LO  is  crystal  con- 
trolled for  stability  and  uses 
FT-243  type  crystals.  The  20 
meter,  WWV,  and  1 5  meter 
bands  are  at  a  frequency 
higher  than  that  at  which 
these  crystals  will  oscillate,  so 
a  multiplier  is  used  to  double 
or  triple  their  fundamental 
output  when  the  bandswiteh 
is  in  these  positions.  This 
multiplier  is  a  class  C  ampli- 
fier whose  output  is  tuned  to 
the  selected  frequency  with  rf 
chokes  and  fixed  capacitors, 

Now  things  really  start  to 
happen.  While  the  converter 
Q2  is  doing  what  is  natural, 
its  output  is  a  real  mess  of 
signals,  and  we  are  only  inter- 
ested in  the  ones  that  are  the 
difference  between  the  LO 
and  rf  frequencies. 

The  unwanted  signal  that 
will  cause  the  most  harm  is 
the   very   strong  one   at  the 


LO  frequency.  If  it  gets  into 
the  BC  set  loop  stick,  over- 
loading will  take  place  and 
there  will  be  birdies  all  over 
the  bands.  To  stop  this  LO 
feedth  rough,  the  converter 
output  is  filtered  by  using  a 
well  shielded  oscillator  coil, 
T1 1  (Fig.  3),  removed  from 
another  BC  set,  and  tuning  it 
with  a  fixed  capacitor  to 
about  1  MHz. 

Because  of  a  long  coaxial 
cable  run  to  this  improvised 
transformer,  Zl  was  fabri- 
cated to  swamp  any  VHF 
parasitics  that  might  develop. 
The  base  of  the  1  MHz  ampli- 
fier Q5  is  connected  to  the 
pick-up  coil  in  T11,  resulting 
in  a  clean  converted  signal 
being  amplified.  It  produces  a 
strong  field  around  rf  choke 
L8,  which  is  tuned  to  about 
0,8  MHz  with  fixed  capaci- 
tors. 


Ti 


BAND    SWITCH 


a 

CA 


r 


& 


C44 
I 


8  0-  MTR 
-ff* — o — 


C43 
33QC-F 


T2-A 
T3-A 
T4-A 
T5-A 


40     S|A 

20 

15  MTR 


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g> 


ANTENNA 


XcR2  "~1gRi 

IINI23  Slhil28 


TO 

T  7 


T7-B 
TO     TS-B 

7  10    79 -e 

Tio-a 


RR     AMPL/R/ER 


RESISTOR-     I/4W 
CAPACITOR-  >0VDC 
SEE    FIGURE   5 
FOfi  ■LltL2.L3iL4l. 
CA  a  CB    VALUES 


CONVERTER   B   LOCAL    OSC/UATOR 

3N14-0 
^0 


FIGURE  3 
©      ©       © 


Yl 


fr 


Y2 


V3«Hft 


II 


'HI 


m 


V4 


This  choke  is  mounted 
close  to  the  BC  receiver  loop 
stick  so  its  field  will  be 
picked  up  with  little  attenua- 
tion. Strong  spurious  signals 
(birdies)  are  unacceptable* 
Therefore,  the  importance  of 
keeping  the  HF  LO  signal  out 
of  the  BC  set,  and  the  BC  LO 
signal  out  of  the  HF  rf  ampli- 
fier cannot  be  overempha- 
sized. Most  of  the  receiver 
shielding  and  parts  placement 
was  made  to  achieve  this 
isolation. 

The  broadcast  receiver  is 
now  able  to  tune  and  detect 
the  different  HF  signals  that 
have  been  converted  to  fre- 
quencies that  are  within  its 
range,  it  is  still  not  ready  to 
be  used  for  a  reliable  contact, 
because  it  needs  at  least  a 
beat  frequency  oscillator  and 
more  selectivity. 

The  BFO  is  a  series-tuned 
Colpitts  type.  It  uses  a  tran- 
sistor BC  set  IF  transformer 
for  the  frequency  controlling 
element  and  a  front  panel 
controlled  capacitor  to  vary 
the  pitch.  Its  output  is  taken 
from  the  small  untuned 
winding  in  the  IF  trans- 
former. 

The  receiver's  fine  selec- 
tivity is  achieved  by  con- 
necting a  crystal  filter 
between  the  collector  of  the 
BC  set's  first  IF  amplifier 
transistor  and  its  output 
transformer.  To  implement 
this,  the  collector  lead  is  dis- 
connected from  its  original 
place,  and  reconnected 
through  a  coaxial  cable  to 
another  identical  IF  trans- 
former located  on  the  V2  MHz 
crystal  filter  and  ANL  circuit 
board  (Fig,  4), 

This  transformer,  T1 2, 
provides  the  input  for  the 
FT- 241  low  frequency  crystal 
Y6  and  the  180  degree  out- 
of-phase  signal  for  the  phase 
control  C20,  When  C20  is 
critically  adjusted  from  the 
front  panel,  stray  signaSs 
shunted  around  Y6  are  can- 
celed   and   the   filter   output 


Fig.  2 


Fig.  3. 


29 


«    c^ 


RESISTOR  -   IMW 
CAPACITOR-    10  VBC 


♦  8  V 


RESISTOR-  I/4W 
CAPACITOR-  IOVOC 
*Y6  FREQUENCY    SAME   AS  BROADCAST 

RECEIVER   l-F  OR  RETUNE  FOR 

4G4.B  KtHr  CRYSTAL 


Fig.  4. 


COIL  -  CRYSTAL    TABLE 

BAND 
{METERS) 

RECEIVER 
FREQUENCY   RANGE 
(MHi) 

HF   AMPLIFIER 

CONVERTER 

CRYSTAL 
HF   LO 

TRANSF. 
SYM. 

TURNS 

WIRE 
IAWS1 

CA 

TRANSF. 
SYM, 

TURNS 

WIRE 

( A  WG ) 

ce 

(pF) 

SYM, 

FREQ. 

LI 

12 

L3 

L4 

80 

3,13-4, |fl 

T\ 

€5 

4 

28 

33 

T6 

65 

7 

28 

47 

Yl 

4735 

40 

6.30-  7.39 

ra 

d£ 

2 

28 

47 

r? 

42 

4 

28 

58 

Y2 

7500 

20 

13.35-14. 40 

T3 

24 

2 

24 

5 

TB 

24 

3 

£4 

47 

Y3 

7475 

13 

20.30-  2J. 50 

-4 

14 

1 

24 

'-.--_ 

ra 

14 

2            24 

33 

Y4 

7350 

WWV 

14.40-15,40 

T5 

24 

2 

24 

IE 

TIO 

24 

a 

24 

39 

Y3 

7975 

COIL  DIAMETER  -  1/4  In.  {.635cm,).     CRYSTALS- FT-243  PRESSURE  MOUNT  TYPE, 
L2*!mfn.  FROM  U  RF  GROUND  SIDE.   LA  3  L3   SAME  SPACING!  CA  >CB.!_UL2>L3>a  L4 
SHOWN  GNFlG.  2 

has     an     extremely     narrow 
bandwidth. 

When  it  is  closed,  it  sends  a 
strong  signal  around  Y6  and 
the  bandwidth  is  useful  for 
SSB     communication.     The 


Fig.  5. 

output  of  Y6  is  kept  at  a  very 
high  impedance  and  con* 
nected  to  gate  1  of  06.  Gate 
2  has  the  BFO  output  and  the 
ANL  bias  feed  to  it.  The  BFO 
is  mixed  with  the  IF  in  this 


manner  to  prevent  strong 
signals  from  pulling  its  fre- 
quency. 

The  gain  of  Q6  is  regulated 
by  the  amount  of  ANL  bias 
at  gate  2.    Its   drain  is  con- 


nected through  another 
coaxial  cable  back  to  the  BC 
set  IF  transformer  at  the 
original  collector  connection 
of  the  first  IF  amplifier  tran- 
sistor. This  completes  the  IF, 
amplifier  circuit  again,  but 
with  the  crystal  filter,  ANL, 
and  BFO  added  to  it 

To  develop  the  automatic 
noise  limited  bias,  the  IF 
signal  at  the  input  of  the 
crystal  filter  is  transformed  to 
a  low  impedance  by  Q7  and 
diode  CR4  changes  it  to  nega- 
tive dc,  filtered  by  C24,  This 
diode  is  biased  to  different 
values  above  cut-off  by  the 
front  panel  control  R26, 

When  the  signal  exceeds 
this  bias,  a  negative  voltage  is 
developed  which  is  subse- 
quently fed  to  gate  2  of  Q6. 

The  gain  of  Q6  will  vary 
with  a  noise  pulse  ail  the  way 
to  cut-off,  depending  upon 
the  setting  of  the  ANL  pot 
R26.  The  diode  limiters  are 
also  part  of  the  AN  L  but  they 
are  not  adjustable.  The  main 
function  of  CR1-CR2  is  to 
prevent  serious  overloads 
from  damaging  any  com- 
ponents when  the  transmitter 
is  keyed,  and  that  of 
CR5-CR6  is  to  prevent  audio 
distortion* 

The  5-meter  circuit  has  an 
unusual  input  network  that 
nulls  out  the  BFO  component 
of  the  IF  signal  so  it  will  not 
deflect  the  meter.  This  is 
accomplished  by  adding  the 
exact  amount  of  180  degree 
out-of-phase  BFO  power  to 
the  input  of  Q9  (Fig.  3). 

It  might  look  like  a  mar- 
ginal balance,  but  I  have  not 
had  to  change  the  original 
adjustment  of  R32,  and  a 
year  has  passed  without  the 
meter  being  slightly  deflected 
by  the  BFO.  The  rest  of  the 
circuit  is  conventional  with  a 
voltage  amplifier  Q9  followed 
by  a  collector  detector  Q10 
that  deflects  the  meter. 

The  final  two  modifica- 
tions require  soldering  inside 
the  BC  set.  One  is  to  add 
manual  IF  gain  control  to 
prevent  overloading,  and  the 
other  to  stabilize  the  collec- 
tor voltage  that  feeds  the  MF 
LO  to  prevent  modulation 
and     drift     To     locate    the 


30 


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or  the  satisfaction  of  owning  the  very  best. 

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transceiver.  The  3750  covers  all  amateur  bands 
1.8-30  MHz  (160-10  meters).  It  utilizes  advanced 
Phase-Lock-Loop  circuitry  with  dual  gate  MOS 
FEPs  at  all  critical  RF  amplifier  and  mixer  stages. 
There's  a  rotating  dial  for  easy  band-scanning  and  an 
electronic  frequency  counter  with  digital  readout 
and  a  memor?  display  that  remembers  frequencies  at 
the  flip  of  a  switch.  And  that's  just  the  beginning. 

Matching  speaker  unit  (3854)  and  complete 
external  VFO  (3855)  also  available. 

See  the  incomparable  Hy-Gain  3750  at  your  radio 
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3855 


We  keep  people  talking. 


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8601  Northeast  Highway  Six;  Lincoln,  NE  68505 


©1976  Hy-Gain 


eoMTB 
Haass 


S.6Q 

-  s.ess 

-  S.TD 
3.T5S 


S.flO 
-  7,16     H  S.9-S5 


S  4  S 

DIAL  SETTING 


Fig.  6.  Typical  calibration  chart 


proper  place  to  do  both  jobs 
will  take  some  looking 
around. 

A  zener  diode,  CR3  (Fig. 
4),  is  connected  across  the 
large  capacitor  on  the  load 
side  of  the  decoupling  resistor 
feeding  the  collector  power 
to  the  rf  circuits.  The  resistor 
is  about  100  Ohms  and  the 
large  can  type  capacitor 
makes  it  fairly  easy  to  locate. 

Next  you  will  have  to  find 
the  forward  biasing  resistor  of 
the  IF  amplifier  base  bias 
divider.  My  receiver  has  only 
one  IF  stage  and  it  was  no 
trouble  to  find.  It  will  be 
about  150k  and  it  feeds  the 
power  we  just  stabilized 
through  the  AM  detector 
diode,  which  also  doubles  as 
the  AGC  generator,  on  to  the 
cold  side  of  the  IF  trans- 
former base  winding.  This 
resistor  is  disconnected  from 
the  stabilized  voltage  and 
reconnected  to  the  wiper  of 
the  front  panel  controlled  rf 
gain  pot,  R1  6  (Fig.  3). 

Construction 

I  assembled  my  receiver  on 
a  1  5  cm  x  1 0  cm  x  5  cm  (6  x 
4x2  inch)  chassis  having  a 
18.4  cm  x  12.7  cm  (714  x  5 
inch)  front  panel.  The  tran- 
sistor AM  broadcast  receiver 
was  selected  because  of  its 
tuning  dial  and  volume  con- 
trol layout.  The  negative  side 
of  its  battery  was  connected 
to  the  ground  plane,  and  the 
speaker  opening  was  covered 
with  a  gold  metal  screen  that 
would  make  a  pretty  good 
shield, 

I  found  later  that  it  had 
only  one  IF  stage,  but  this 
certainly    did    not  affect   its 


sensitivity  or  degrade  the 
project.  The  BC  set  must  have 
extension  shafts  epoxied  to 
its  tuning  and  volume  control 
dials  so  they  can  be  operated 
outside  the  front  panel.  The 
new  tuning  dial  is  a  vernier 
type  and  had  to  be  mounted 
on  a  1.1  cm  (7/16  inch) 
homemade  spacer  so  it  would 
fit  on  the  capacitor  shaft. 

The  front  panel  controls, 
5-meter,  speaker  and  phone 
jack  are  located  so  that  they 
are  easily  accessible.  After  the 
BC  set  has  had  its  IF  retuned 
to  match  the  filter  crystal,  it 
is  fastened  to  the  front  panel 
with  two  #2-56  bolts.  One  of 
the  bolts  has  a  soider  lug 
under  its  nut  so  the  BC  set 
ground  plane  can  be  con- 
nected   to    the    metal    front 


panel  through  it 

The  outboard  circuits  that 
convert  the  BC  set  into  our 
communication  receiver  are 
made  on  pieces  of  "vector" 
breadboard  material,  and  the 
components  are  soldered  to 
press-in  terminals.  They  were 
all  made  as  srnail  as  possible 
and  tested  before  they  were 
mounted,  using  spacers,  in 
the  main  chassis. 

The  bandswitch  has  two 
levels  with  three  poles  on 
each.  All  rf  amplifier  con- 
nections are  kept  on  one 
level,  with  converter  and  HF 
LO  connections  on  the  other. 
A  lot  of  effort  was  spent 
trying  to  keep  the  leads  short 
and  separated  from  each 
other,  but  it  still  turned  out  a 
mess.  However,  it  works 
better  than  anyone  could 
have    imagined.    I    used   #22 

AWG  solid  insulated  wire  for 
the      interconnections,     and 

bare  wire  for  the  jumpers. 

All  rf  transformers  are 
mounted  on  the  top  of  the 
chassis  and  are  well  shielded. 
The  converter  transformers 
are  preassembled  on  a  plate 
that  fastens  to  a  flange 
around  a  cut-out  in  one  end 
of  the  chassis.  These  coils 
project  into  the  underside  of 
the     chassis,    isolating    them 


from  the  rf  amplifier  input. 
The  tuning  is  broadened  by 
the  heavy  loading  of  both  sets 
of  coil  with  more  primary 
(untuned)  turns  than  would 
be  used  for  high  Q  operation. 

I  used  as  much  shielding  as 
I  could  make  without  getting 
sick.  It  is  very  important  to 
keep  the  outputs  of  the  two 
local  oscillators  out  of  each 
other's  converters,  and  the 
BFO  harmonics  out  of  the 
HF  rf  amplifier. 

The  cabinet  is  fabricated 
out  of  aluminum  sheet  and 
provides  the  shielding  needed 
to  keep  out  broadcast  station 
signals.  The  front  and  rear 
panels  are  marked,  after 
painting,  with  Datak  dry 
letter  transfers,  and  then 
sprayed  with  clear  plastic  to 
prevent  them  from  being 
worn  off.  When  the  wrap- 
around top,  bottom,  and  side 
piece  is  buffed  carefully,  the 
receiver  has  a  professional 
appearance. 

My  semiconductors  were 
selected  because  they  were 
readily  available  to  me.  The 
SE  4010  transistors  came 
from  an  old  printed  wiring 
board  bought  from  a  mail 
order  house.  When  I  ran  out 
of  these,  I  used  2N2222  tran- 
sistors   from   another   board. 


inn 


al»Mli;r::iHij^      <SHMW*  '■  ' ' 


^m.. 


-  |iw.i,i,,,.|p.»*l*iniii  l^!B»»!"rtfrt,(WW,i'i     ',ii|i,ii.i,-Jmim»imtHW^. 


Fig.  7.  Looking  toward  front  pane!  with  top  half  of  cabinet  removed.  Top>  left  to  right: 
S-meter,  I  MHz  coupler  next  to  loop  stick  antenna,  AM  broadcast  set.  Bottom:  HF  LO  crystal 
shield,  S-meter  amplifier  over  the  rf  transformer  shield }  crystal  filter  and  ANL  circuit  board \ 


32 


Both  are  replaceable  with 
Motorola  HEPS 5,  a  NPN  rf 
transistor. 

The  MOSFETs,  Q1,  Q2 
and  Q6,  are  the  contents  of  a 
Radio  Shack  Archer  Pack 
#276-628  called  "Three 
MOSFET  N  Channel  Tran^ 
sistors."  You  must  watch 
how  you  solder  these  units  in 
place.  Keep  all  the  leads 
shorted  together  during  the 
process  or  the  gates  will 
surely  be  ruined.  After  they 
are  in  place  nothing  seems  to 
be  able  to  keep  them  from 
working. 

Alignment 

I  aligned  the  tuned  circuits 
of  my  receiver  using  equip- 
ment commonly  found  in  the 
ham  shack.  Operation  one  is 
to  tune  the  rf  and  converter 
transformers  to  the  center 
frequency  of  their  bands 
using  a  grid  dip  meter  for  an 
indicator. 

Next,  you  must  have  the 
shields  fastened  into  place, 
power  switch  placed  on,  rf 
gain  turned  fully  on,  audio 
gain  one  quarter  up,  ANL  off, 
BFO  off,  phase  capacitor 
fully  closed,  and  the  antenna 
input  supplied  with  a  signal 
from  a  VFO.  The  coupling 
must  be  very  loose  to  the 
VFO. 

The  coupling  recom- 
mended is  two  50  Ohm  resis- 
tors side  by  side,  one  fed  by 
the  VFO  and  the  other  across 
the  coax  connected  to  the 
receiver  antenna  terminal. 
There  is  no  hard  electrical 
connection  between  the  two 
resistors  {only  the  rf  field), 
and  the  spacing  between  the 
two  should  be  variable. 

Back  on  the  receiver,  an 
oscilloscope  is  connected  to 
the  input  of  the  filter  crystal, 
Y6,  using  a  high  Z  probe.  The 
slugs  in  T1 1  and  T12  are 
centered,  and  the  bands  witch 
set  to  the  VFO  frequency 
range.  The  VFO  or  the  re- 
ceiver dial  is  varied  until  the 
rf  is  picked  up  and  a  xh  MHz 
IF  signal  is  seen  on  the  scope. 
Til,  T12,  and  the  rf  con- 
verter transformer  combina- 
tion, when  switched  in>  are 
adjusted  until  the  IF  signal  is 
maximum  amplitude. 


Fig.  5.  Looking  toward  front  panel  with  ail  shields  removed,  along  with  cabinet.  Left  to  right: 
converter  transformers  on  loose  panels  HF  LO  crystals  on  home  brew  holder }  1  MHz  coupler,  rf 
transformers,  rf  amplifier,  BCset,  S-meter  amplifier,  crystal  fitter,  ANL  hoard. 


The  rf  gain  should  be  re- 
duced along  with  the 
coupling  to  the  VFO  during 
these  adjustments,  to  keep 
the  scope  presentation  at  an 
amplitude  easy  to  see  but  not 
overloading  the  circuits 
(about  a  volt  peak). 

Connect  the  scope  probe 
to  the  drain  of  Q6  and  retune 
the  receiver  dial  for  a  maxi- 

w 


mum  display.  Set  the  phase 
capacitor  to  its  minimum 
bandwidth  position,  which  is 
found  by  moving  the  VFO 
dial  around  the  detected  fre- 
quency. Move  the  scope 
probe  back  to  the  input  of 
Y6  and  tweak  up  T12  and  the 
first  BC  set  IF  transformer  so 
that  their  bandpass  is 
centered  on  Y6's  frequency. 


Connect  the  scope  to  the 
output  of  the  last  BC  set  IF 
transformer  and  tweak  up  the 
remaining  BC  set  IF  trans- 
formers so  they  are  also 
center  tuned  to  Y6's  fre- 
quency. The  BFO  is  switched 
on,  the  pitch  capacitor 
centered,  and  the  slug  in  T13 
adjusted  for  a  zero  beat, 
noted   at  the  scope  and  the 


Fig.  9.  Underside  of  chassis;  Left  to  right;  converter  transformers  on  loosened  panel,  HF  LO 
converter  circuit  board  in  back  of  bands  witch,  LO  multiplier,  BFO  in  back  of  shield,  /  MHz 
amplifier. 


33 


tone  at  the  speaker. 

The  last  and  simplest 
adjustments  are  made  to  the 
S-meter  calibration  pots,  R32 
and  R33.  Without  an  rf  signal 
being  applied  to  the  receiver 
input,  rotate  R34  fully  clock- 
wise, place  the  BFO  switch 
on,  and  adjust  R33  to  a  posi- 
tion where  Ml  indicates  zero. 
When  an  rf  signal  is  present, 
Ml  will  deflect  to  a  value 
proportional  to  its  power- 
There  is  no  clear-cut  amount 
of  rf  power  per  S  unit,  so  set 
R33  to  a  place  where  what 


you  believe  is  a  S9  signal  in 
the  phones  reads  S9  on  the 
meter. 

If  you  use  a  dial  marked  1 
through  100  like  ]  did,  a 
calibration  chart  will  have  to 
be  made.  One  curve,  and  oniy 
erne,  is  needed  for  all  bands, 
because  the  BC  set  does  the 
tuning  each  time.  Fig,  6 
shows  how  an  easy-to-read 
chart  may  be  laid  out.  The 
points  for  the  curve  are 
located  by  picking  up  the 
output  of  a  100  kHz  crystal 
calibrator,   and    knowing  the 


frequency  of  the  converter 
crystals.  Subtracting  the  HF 
rf  frequency  from  it  will 
locate  the  band  scales  on  the 
chart 

Conclusion 

This  whole  project  was  a 
very  satisfying  success.  How- 
ever, you  could  always  do 
better  if  you  had  a  second 
chance,  The  next  time,  1 
would  replace  the  FT-243 
style  crystals  with  smaller  de- 
vices, even  though  it  would 
run  up  the  cost. 


Also,  their  frequencies 
would  be  such  that  the  LO 
multiplier  could  be  elim- 
inated, reducing  the  battery 
drain  by  5  mA.  I  believe  that 
1  would  make  the  front  panel 
larger  to  accommodate  a 
different  type  of  dial.  I  can- 
not find  any  fault  with  the 
semiconductor  devices  or  the 
BC  set,  so  I  would  stick  with 
them. 

In  fact,  the  whole  receiver 
fits  and  works  so  well  beside 
my  keyer  that  I  am  in  no 
hurry   to  change  anything.  ■ 


Ham  Help 


Many  people  express  an  interest  in 
ham  radio,  but  find  it  difficult  to 
locate  a  ham  to  answer  their  ques- 
tions, peak  their  curiosity,  and  enroll 
them  in  a  local  area  class.  As  public 
pressure  for  our  frequencies  increase, 
we  must  increase  both  our  public 
awareness  and  our  numbers  in  order 
to  survive  and  grow.  Through  a  new 
program  called  Ham  Help,  we  hope  to 
be  the  link  between  the  prospective 
ham  and  you,  the  local  radio  clubr  the 
neighbor  hood  ham,  and  the  nearby 
radio  class.  Here's  how  it  works, 

A  prospective  ham  will  call  the 
Ham  Help  number,  ILL-1676.  The  24 
hour  line  will  be  answered  by  John 
Russell  WB9UEC,  Ham  Help  Chair 
man,  or  an  answering  machine,  After 
getting  the  name,  address,  and  phone 
number  of  the  prospective  ham,  John 
will  call  a  volunteer  ham  in  the 
prospect's  neighborhood.  The  volun- 
teer will,  in  turn,  call  the  prospect, 
and,  hopefully,  take  a  personal 
interest  En  the  newcomer, 

A  program  like  this  will  obviously 
only  succeed  if  all  area  clubs  will 
volunteer  information  on  area  classes 
and  keep  the  Ham  Help  file  current. 
Here  is  what  your  radio  club  can  do  to 
help  make  it  work: 

INFORM',  Call  the  Ham  Help  line 
to  let  John  know  about  classes  — 
include  specifics  such  as  datesr  times, 
location,  and  who  to  contact.  Please 
don't  assume  we  have  all  the  informa- 
tion we  need;  we  can  only  get  it  from 
you.  Continual  updating  of  class  infor- 
mation is  essentia!  for  the  program  to 
work. 

REFER.  Refer  others  to  Ham  Help. 
We  will    be  glad  to  be  the  clearing 
house  for  all  classes  in  the  area.  Have 
them  call  ILL  1676  and  we'll  take  it 
from  there. 

VOLUNTEER:  We  need  volunteer 
hams  to  call  back  prospective  hams 
that  may  call  from  your  area.  Invite 
them  to  your  shack.  Tell  them  about  a 
class  in  your  area  (John  will  give  you 
the  info}.  Bringing  a  new  ham  into  the 
fold  is  a  rewarding  experience  that  is 
good  for  you,  your  radio  club,  and  the 
hobby.    Call    in    to    Ham    Help    and 


volunteer  your  services  as  an  "Elmer" 
in  your  area.  If  your  club  would  like 
to  handle  afl  requests  from  a  certain 
area,  let  John  know,  and  we  will  be 
glad  to  refer  prospects  to  you.  A  good 
way  to  increase  membership  in  your 
club! 

Let  me  stress  that,  though  CFMC  is 
funding  this  program,  we  wish  it  to  be 
a  truly  inter- club  project.  The  Chica- 
goland  area  is  ripe  for  a  program  of 
this  type.  Our  hobby  is  the  finest  in 
the  world  —  it's  time  we  began  to 
show  it  off ! 

Only  through  your  club's  {and  Its 
members')  participation  can  Ham 
Help  work.  We  ask  that  you  print  this 
in  your  bulletin  or  newsletter,  and 
announce  it  at  your  next  meeting. 

We  are  banking  on  your  continual 
support  of  Ham  Help  to  make  this 
program  a  huge  success,  and  to  bring 
new  blood  into  our  hobby  and  our 
clubs. 

Rich  Casey  WA9LR I 

President 

Chicago  FM  Club 

Arlington  Heights  IL 

By  way  of  background  informa- 
tion: I  am  67,  still  hold  a  lifetime  FCC 
permit  to  operate  on  the  former 
marine  2  to  4  meg  band,  hold  the  first 
renewal  of  my  CB  license  (but  have 
become  disenchanted  with  that  crowd 
and  do  not  operate  my  Johnson  323 
Messenger),  have  built  a  half  dozen 
Heathkits  (from  stereos  through 
VTVM  to  tachometers),  and  have  just 
been  nudged  by  a  summertime  neigh' 
bar,  whose  permanent  address  is 
Cleveland,  to  seriously  approach  ham 
radio,  I  have  one  of  his  back  issues  of 
GSF and  the  July  '76  issue  of  73. 

Up  here  in  the  puckerbrush  at 
Bridgton,  Maine,  amateur  radio  is 
practically  unknown.  I  can't  find  a 
soul  who  can  give  me  counsel. 

I  have  written  ARRL  for  a  half 
dozen  books  (not  yet  received),  and 
have  ordered  from  Heath  a  starter  set 
of  code  practice  records  and  practice 
key  toward  going  for  Mo  vice,  or  if  I 
have  enough  practice  time,  to  try  for 
General  in  one  jump. 


From  my  copy  of  FCC  Rules  and 
Regs,  VoL  VI,  I  have  found  Bangor, 
Maine,  is  the  semi-annual  location  of 
examinations.  How  do  I  find  out 
when  and  how  much?  How  do  I  find 
out  if  there's  a  General  in  the  area 
who  could  examine  me  for  Novice? 

How  do  I  find  out  -  in  a  HURRY 
—  what  licensed  hams  have  known  for 
a  long  time?  Huh?  Time  is  of  the 
essence,  because  on  this  side  of  60 
there's  a  hell  of  a  lot  less  of  it 
remaining  than  there  was  on  the  front 
side ! 

From  what  little  1  know  now,  80 
through  10m  is  the  spectrum  that 
interests  me,  and  I  am  looking  for  a 
used  receiver,  5  band,  SSB,  all  solid 
state,  in  perfect  working  order,  to  do 
a  little  listening,  and  to  gather  some 
education  on  the  way.  To  get  some 
good  out  of  it,  an  antenna  is  a 
prerequisite,  and  some  ideas  on  a 
simple  dtpote  which  I  can  hang 
between  a  couple  of  trees  would  be 
most  welcome,  Lightning  arresters, 
which  are  effective,  are  a  must  in  this 
mountain  country,  where  it  gets 
pretty  "snappy"  now  and  again. 

As  you  can  plainly  see,  I'm  not 
asking  for  much  help,  just  the  whole 
ball  of  wax  I 

Whatever  assistance  you  may  he 
able  to  provide  would  be  most 
welcome.  Thank  you  very  much. 

Charles  A,  J u rack 

P.O.  Box  145 

Bridgton  ME  04009 

For  those  in  our  area  needing  help 
for  Novice  through  Extra,  please  con- 
tact; Carthage  Amateur  Radio 
Society,  c/o  Mr,  Dan  Waters,  Voca- 
tional Education  Bldg.,  6th  and  River 
Streets,  Carthage  MQ  64836. 

We  meet  each  Wednesday  evening 
at  7  pm  local  time  at  the  vocational 
building, 

Howard  Gravitt  W0CZT 
Carthage  (VI 0 

I  really  enjoyed  your  articles  about 
computers  in  the  Aug.  76  issue  of  73. 
I  am  14  years  old,  and  before  we 
moved  to  Texas,  I  used  to  be  real 
good  at  computer  programming.  The 
middle  school  that  I  used  to  go  to  had 
several  terminals  connected  via  tele- 
phone to  the  main  computer  at  West- 


field  High  School.  The  computer  was 
a  "Digital"  PDP/1 1,  BASIC  language. 
The  school  I  went  to  taught  computer 
programming  starting  in  grade  6.  (The 
name  of  the  school  is  South  Middle 
School.)  When  we  moved  here,  I 
found  out  that  computer  program 
ming  is  not  taught  until  11th  grade!  If 
there  is  any  way  that  I  can  use  a 
computer  near  here,  will  you  please 
let  me  know?  I  really  enjoyed  com- 
puter programming  in  BASIC  language 
and  would  love  to  do  it  again. 

Tom  Trusty 

2613  Lynnwood  Dr« 

Arlington  TX  76013 

(817)27^7998 

P.S.  I  am  waiting  for  my  Novice  call 
to  come  back  from  the  FCC.  I  took 
the  written  test  about  1  month  ago, 
and  the  code  test  a  few  weeks  before 
that. 

I  think  amateur  radio  is  great,  and  I 
would  like  to  add  my  name  to  your 
Ham  Help  list.  I  am  willing  to  help 
any  interested  person  get  started  in 
amateur  radio  in  the  Michiana  area. 
All  they  have  to  do  is  drop  a  line  to 
me. 

Ron  Lula  WB9WXO 

55428  Meadowview  Ave, 

South  Bend  IN  46628 

We  would  appreciate  it  if  you 
would  list  us  in  your  "Ham  Help" 
column.  73  is  a  lot  easier  to  read  than 
QST  because  it  is  at  our  level.  We 
already  have  2  receivers,  but  they  are 
not  very  good.  Thank  you  very 
much  Ml! 

Mark  and  Dave  Bud  a 

120  Pierrepont 

Dunlap  I A  51529 

(712J-643  2273 


I      need 
Novice}, 


help     in     Colorado     (for 

Mark  Pollard 

710  Mohawk 

Box  3345 

Boutder  CO  80303 


I    need    help   to   get    into   amateur 
radio. 

Tom  Griffith 

Sequoyah  Estates 

Morristown  TN  37814 


34 


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New  York,  N.Y. 

CFP  Enterprises 
Lansing,  N.Y. 

Electronic  Distributors 
Muskegon,  Michigan 


Goldstein's 

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35 


To  those  who  are  used  to 
struggling  with  the 
vacuum  lube  version  of  the 
electronically  regulated 
power  supply,  the  IC  voltage 
regulators  can  be  quite  an 
experience. 

Within  the  realm  of  what 
is  possible  when  working  with 
any  infernal  electronic  device, 
to  know  them  is  almost  to 
love  them. 

While  they  come  in  a  wide 
variety  of  sizes,  shapes  and 
internal  configurations  for 
specialized  purposes,  most  of 
the  jobs  that  the  beginner  and 
even  the  more  advanced 
builder  would  have  can  be 
handled  with  only  a  few  of 
the  most  commonly  available 
types. 

Here  comes  the  Tun  part. 
Using  these  IC  regulators  is 
almost  as  simple  as  plugging 
in  a  transistor.  The  ones  of 
most  interest  are  three 
terminal  devices  and  require 
only  a  few  external  parts. 

The  IC  regulators  are 
classified  as  linear  devices. 
While  there  are  a  number  of 
ratings  which  might  apply, 
and  a  number  of  ways  to  get 
a  more  complex  regulator 
using  them,  it  is  the  simple 
way  we  want  to  explore, 

As  most  of  this  series  has 


been  devoted  to  the  digital 
ICs,  the  first  voltage  that 
would  be  of  interest  is  the 
regulated  five  volts  dc  that 
the  digital  ICs  require. 

For  this  job  there  are  two 
very  common  regulators 
which  you  will  find  in  many 
of  the  circuits.  They  are  the 
LM309H  and  the  LM309K. 
(The  LM109H,  K  are  almost 
identical  and  are  also  com- 
monly available,) 

As  can  be  seen  from  the 
numbers,  they  are  very  simi- 
lar to  each  other.  There  are 
two  practical  differences 
between  them:  the  package 
they  are  in  and  the  power 
they  will  handle. 

The  LM309H  is  in  a  TG-5 
transistor  type  package  and 
will  handle  about  200  mA. 
The  LM309K  is  in  the  TO-3 
type  package  and  will  handle 
an  Ampere  of  current. 

Fig.  1  shows  the  pin  con- 
figurations of  the  two.  These 
are  from  the  bottom  of  the 
package.  While  the  DIP  (Dual 
Inline  Package)  ICs  are 
counted  from  the  top  of  the 
device,  these  are  from  the 
bottom,  like  transistors. 

This  may  be  confusing 
until  you  get  used  to  it,  since 
you  may  be  working  from  the 
top  with  a  breadboard  matrix 


or    other    construction   tech- 
nique. 

With  just  three  pins,  you 
don't  have  a  lot  of  choice  to 
make.  One  is  the  voltage 
input,  one  is  the  regulated 
output  and  ont  is  the  ground 
connection.  It  would  be  hard 
to  go  wrong.  Just  make  sure 
which  pin  is  which. 

Fig.  2  shows  how  the 
device  hooks  into  the  power 
supply  circuit,  and  its  basic 
external  components.  While 
the  device  can  be  used  with  as 
high  as  35  volts  input,  there 
are  dangers  to  doing  this 
which  will  be  explained  later, 
Assume  that  the  supply 
shown  is  in  the  nine  to  twelve 
volt  range. 

It  is  very  important  to 
understand  the  purpose  of  C2 
and  C3.  They  are  not  there  to 
supply  additional  power 
supply  filtering  in  the 
ordinary  sense,  A  typical 
value  for  CI  would  be  in  the 
neighborhood  of  5000  uF,  so 
the  two  additional  capacitors 
with  those  values  would  have 
miniscule  effect. 

The  technical  data  lists 
them  as  optional  and  not 
being  needed  for  all  applica- 
tions, but  don't  you  believe 
it.  So  what  are  they  there 
for? 


How  Do  You 
Use  ICs? 


-  -  part  IV 


Specifically,  they  are  there 
to  prevent  self-oscillation  of 
the  regulator  IC  and  to  pre- 
vent external  pulses  from 
upsetting  internal  operation. 
Self-oscillation? 

A  simple  transistor  regu- 
lator consists  of  a  pass  tran- 
sistor to  handle  the  current, 
controlled  by  several  signal 
type  transistors.  As  the 
voltage  varies,  it  creates  a 
signal  which  goes  to  the  con- 
trol circuitry  which  tells  the 
pass  transistor  what  to  do  to 
hold  the  voltage  steady. 

The  LM309  has  about  19 
transistors  and  a  heap  of 
other  parts  in  it*  Even  though 
there  are  only  three  pins  on 
the  outside,  there  is  a  whole 
lot  going  on  inside. 

As  with  any  transistor, 
there  is  always  the  danger  of 
it  breaking  into  oscillation 
since  it  has  the  overall  effect 
of  being  a  high  gain  device, 

This  also  means  that  it  is 
susceptible  to  pulses  from  the 
outside  getting  in  to  cause 
trouble. 

Even  though  this  may  not 
be  a  problem  in  ail  cases,  the 
reports  of  IC  equipment  and 
experimentation  so  far  have 
come  up  with  another  reason 
why  they  should  be  used  as  a 
matter  of  course. 

ICs  seem  to  find  the  signal 
they  want  in  normal  opera- 
tion. This  normal  operation 
usually  includes  square  waves 
which  means  there  are  going 
to  be  harmonics,  spikes  and 
so  forth. 

While  ICs  seem  to  thrive 
on  a  diet  of  crud  and  garbage 
like  that,  the  rest  of  the 
world  is  not  so  tolerant.  It 
would  seem  prudent  to  try  to 
remove  as  much  of  it  as 
possible  from  the  nearby  en- 
vironment. 

Shielding  and  bypassing 
should  be  employed  as  a 
matter  of  course  to  help  keep 
this  stuff  from  getting  to  the 


OUT 

*.  ]  GROUND 
(CASE  J 


Q ROUND 
$  (CATEI 


T0-SIH] 


TO-3(K) 


Alexander  MacLean  WA2SUT/NNNQZVB 
1  8  Indian  Spring  Trail 
Denville   NJ  07834 


Fig.    L   LM309H  (K)  5  voit 
regulator. 


36 


^Cl  ^zcs 


5QCK>*F 


LM309 


2Z 


-a  »5V 
REGULATED 


Fig.  3.  LM340T(K)  regulator.  Code  number  includes  milage. 
LM340T  (or  K)-(5.0,  6.0,8.0,  I2t  J5t  18  or  24). 


0  > 


m 


Fig.  2, 


outside  world. 

The  regulator  bypass 
capacitors  will  not  only  help 
to  protect  it  from  itself  and 
the  rest  of  the  circuit,  but 
will  help  keep  down  the 
amount  of  damage  that  can 
be  caused  to  other  equipment 
from  interference. 

While  the  regulator  can  be 
located  any  reasonable  dis- 
tance from  the  supply,  care 
should  be  taken  with  the 
placement  of  these  capaci- 
tors. 

While  most  of  the  IC  parts 
values  appear  to  have  quite  a 
bit  of  leeway ,  these  appear  to 
be  specific  values  and  should 
not  be  skimped  on. 

As  with  any  bypass  capaci- 
tor, locate  ihem  as  close  as 
possible  to  the  regulator  itself 
and  keep  the  leads  as  short  as 
possible. 

While  these  two  will 
handle  the  bulk  of  the  jobs 
you  will  have  to  do  with 
digital  IC  power  supplies, 
there  are  many  projects  that 
will  require  a  wider  range  of 
voltages. 

Most  of  this  can  be 
handled  by  the  LM340K  or 
the  LM340T  positive  voltage 
regulator  series.  Fig.  3  shows 
the  pin  configuration  of  the 
two  and  the  chart  of  available 
output  voltages. 

The  basic  difference 
between  the  two  is  the 
package,  The  LM340T  is  in 
the  TO-220  transistor  package 
and  the  LM340K  is  in  the 
TO- 3  transistor  package. 

Either  model  will  handle 
an  Ampere  of  current  output 
with  care.  Fig.  4  shows  how 
this  regulator  hooks  into  the 
main  circuit. 


-  O 

A  < 


twoctj 


70-31  rt  :■ 


As  the  schematic  shows, 
the  same  values  are  used  for 
the  bypass  capacitors  with 
this  IC  as  with  the  LM309 
series  regulators. 

The  same  precautions 
should  be  taken  with  the 
placement  and  the  lead  length 
—  as  close  and  as  short  leads 
as  possible. 

Fig.  5  shows  the  negative 
version  of  the  LM34H  This  is 
the  LM320T(K).  Notice  that 
there  is  almost  the  same  range 
of  voltages  available.  Also 
notice  that  the  pin  configura- 
tion is  slightly  different.  This 
ts  important. 

The  negative  input  is  also 
connected  to  the  case  which 
can  then  be  connected  to 
chassis  ground,  thus  keeping 
chassis  ground  at  negative 
potential  if  desired. 

Notice  in  Fig,  6  that  there 
is  a  ground  symbol  used 
rather  than  the  familiar 
chassis  ground.  This  is  con- 
fusing as  it  is  not  the  old 
meaning  which  was  literally 
an  earth  ground^  as  opposed 
to  the  chassis  common  point 
which  may  or  may  not  have 
also  been  grounded. 

Here  what  is  intended  is 
the  circuit  common  point, 
and  not  necessarily  a  connec- 
tion to  either  the  metal 
chassis  or  to  an  earth  ground. 

Wilh  solid  state  work  there 
is  often  the  problem  that  the 
circuit  common  connection 
can  be  either  plus  or  minus 
and  may  not  necessarily  be 
either  chassis  ground  or  earth 
ground,  and  either  plus  or 
minus  potential  may  be  con- 
nected to  the  chassis  or 
ground  independently  of  the 
circuit   common   connection. 

It  makes  for  quite  a  few 
possible  combinations  which 
must  be  carefully  watched  for 
in  the  circuit.  ICs  are  usually 
more  straightforward  in  this 


Fig,    5.   LM320T(K)  negative  vol  luge  regulator.   LM320T{K) 
(5A  5.2,  6.0,  8 A  12,  tS}  18 or  24). 


respect  than  transistors. 

There  is  one  big  difference 
in  the  circuit  which  is  imme- 
diately apparent  in  the  sche- 
matic (Fig.  6),  This  is  the 
value  of  the  bypass  capaci- 
tors. 

They  are  ten  times  bigger 
than  those  for  the  positive 
regulators.  Also  they  are 
rather  specific  about  the  type 
of  capacitor  that  is  to  be 
used.  They  should  be  solid 
tantalum.  Those  are  the  mini- 
mum values  that  should  be 
used,  They  can  be  higher  if 
convenient. 

About  now  panic  is 
starting  to  set  in  as  you  try 
and  figure  out  where  to  get 
solid  tantalum  capacitors.  No, 
you  don't  have  to  try  a  mid- 
night raid  on  Cape  Kennedy. 
These  are  a  fairly  common 
surplus  item.  Usually  the 
same  catalogs  that  have  the 
ICs  you  want  will  also  list  the 
solid  tantalum  capacitors  you 
need  to  go  with  them. 

While  there  are  applica- 
tions where  you  might  want 
to  build  a  negative  regulated 
supply  by  itself*  most  of  the 
time  working  with  a  separate 
supply  you  have  only  to 
switch  the  leads  to  do  the 
job.  This  circuit  was  shown  to 
simplify  a  larger  supply. 

There  is  one  area  where 
you  will  certainly  want  this 
type  of  negative  supply.  This 
is  when  you  get  into  working 
with  the  IC  op  amps  or  other 
ICs  which  require  a  dual 
polarity  supply. 

These  ICs  make  it  very 
simple  to  get  your  plus  and 
minus  supply.  All  you  have  to 
do   is  put  a  negative  and  a 


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positive  supply  back  to  back 
and  you  have  it  made. 

This  is  shown  in  Fig.  7.  As 
can  be  seen,  this  is  virtually 
the  same  circuit  as  the  two 
individual  supplies,  but  now 
they  are  both  together.  The 
only  thing  that  has  been 
added  is  two  diodes. 

For  this  type  of  supply 
you  just  choose  two  regula- 
tors with  the  same  output 
voltage,  whatever  is  desired. 
These  two  were  intended  for 
just  this  type  of  service. 

The  diodes  are  a  protective 
device  to  let  the  regulators 
start  up  looking  into  a  com- 
mon load.  They  may  also 
serve  the  purpose  of  pre- 
venting a  wrong  polarity 
voltage  from  getting  from  one 
regulator  into  the  other. 

Notice  that  they  are 
reverse  polarity  to  the  supply 
each  is  across  and  would 
block  the  voltage  from  the 
other  where  a  load  resistor 
would  not. 

The  diodes  are  rated  al  the 
regulator  short  circuit  current 
rating.  For  12  and  15  volt 
dual  supply  (one  Amp),  a 
1N4720  is  listed.  For  a  15 
volt  200  mA  supply,  a 
1N4001  is  listed. 

That  is  the  overall  survey 
of  the  basic  type  of  supply 
you  will  be  working  with. 
While  there  are  far  more  com* 
plex  configurations  to  handle 
extreme  situations,  these  will 
serve  for  almost  anything  you 
might  want  to  try. 


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Fig,  Z  Dual  polarity  supply.  *Sol id  tantalum, 


Within  the  range  of  simple 
variations  on  the  basic  design 
you  will  be  able  to  get  even 
more  practical  advantage. 
However ,  before  getting  into 
variations,  a  few  words  are  in 
order  on  the  preservation  of 
these  devices. 

While  they  are  quite 
rugged  when  used  as  in- 
tended, as  all  transistorized 
equipment,  they  are  quite 
intolerant  of  any  mistakes 
you  might  make. 

The  easiest  mistake  to 
make  is  with  the  internal 
device  dissipation.  Most  of 
these  regulators  will  accept  a 
voltage  input  of  up  to  35 
volts  and  still  give  the  re- 
quired voltage  output,  but 
there  is  a  built-in  booby  trap. 

Assume  that  you  want  five 
volts  for  a  digital  circuit  and 
have  available  a  twenty-four 
volt  supply.  You  could 
simpiy  add  the  regulator 
circuit  as  shown  in  the 
drawing  and  you  would  get 
the  five  volts  output,  up  to  a 
point. 

Under  a  light  load,  you 
would  probably  be  OK,  but 
when  you  started  to  draw 
much  current,  good-bye  IC. 
This  is  the  internal  rating 
problem. 

Assume  that  you  want  to 
draw  one  full  Ampere  of  cur- 
rent through  this  regulator. 
With  five  volts  out  and  an 
Input  of  twenty-four  volts, 
you  are  left  with  nineteen 
volts  to  deal  with. 


T^C3 


Fig.  5. 


At  one  Ampere  through 
the  regulator^  that  means 
almost  twenty  Watts  has  to 
be  accounted  for.  It  helps  to 
remember  that  this  is  a  regu- 
lator not  a  power  resistor, 
and  should  not  be  used  as 
one. 

Some  of  these  regulators 
can  go  a  little  over  their 
ratings  and  may  be  more  for- 
giving with  the  use  of  the 
proper  heat  sinks,  but  there 
comes  a  point  where  you 
have  troubles. 

Most  of  the  regulators 
such  as  the  LM309  series  are 
built  with  an  internal  shut 
down  feature  for  when  the 
going  gets  hot,  but  even  then 
you  don't  have  to  go  asking 
for  trouble. 

There  is  one  very  simple 
way  to  deal  with  this 
particular  problem.  Use  a 
dropping  resistor.  This  is 
shown  in  Fig.  8,  The  value  is 
quite  easy  to  figure  once  you 
know  what  you  are  looking 
for. 

Most  of  these  regulators 
are  designed  to  operate  with 
anything  from  one  volt  over 
their  rated  output  voltage  up 
to  their  limit.  To  leave  some 
margin,  figure  on  a  two  volt 
margin. 

In  the  example  shown,  the 
output  is  to  be  five  vo!ts  and 
the  input  is  twenty-four  volts. 
The  desired  input  is  seven 
volts,  two  more  than  the 
device  output.  Assume  that 
the  maximum  current  of  one 
Ampere  is  to  be  drawn. 

This  means  that  the  re- 
sistor must  drop  seventeen 
volts.  This  works  out  to  a 
seventeen  Ohm  resistor.  If 
you  want  to  be  very  safe,  use 
a  20  Ohm  resistor. 

The  power  involved  is 
seventeen  Watts.  Use  a 
twenty    Watt  resistor   at  the 


minimum.  Most  of  the  time 
for  experimental  work  you 
will  not  be  drawing  the  full 
output,  but  it's  nice  to  be 
prepared. 

While  this  might  be  an 
extreme  example,  it  is  within 
the  range  of  what  might  be 
encountered  when  you  are 
working  with  what  you  have 
on  hand.  It  points  out  your 
most  effective  rule  of  thumb. 

If  you  want  to  have  the 
maximum  reliability  of  the 
circuitry  when  you  are  exper- 
imenting or  designing,  stay  as 
far  within  the  ratings  as  you 
possibly  can. 

The  simplest  thing  to  do  is 
to  start  with  the  voltage  you 
plan  to  use  as  the  input 
source  and  then  figure  what 
the  full  load  current  and 
power  would  be  through  the 
regulator.  As  long  as  it  is 
within  the  device's  ratings, 
you  would  be  safe. 

It  would  be  better  to  use 
the  resistor  as  a  matter  of 
course,  figuring  it  as  in  the 
example  for  two  volts  more 
than  the  output  of  the  regu- 
lator. 

This  is  based  on  a  steady 
supply  voltage.  If  the  supply 
voltage  drops  under  load,  you 
may  have  to  determine  the 
resistor  value  experimentally 
for  the  correct  input  to  the 
regulator.  You  should  have 
some  margin  to  work  with 
above  the  two  volts  you  are 
aiming  for. 

In  this  case  you  want  to 
make  sure  that  under  full 
load  you  get  the  required 
input  to  the  regulator.  Under 
light  load  a  higher  input  can 
be  tolerated  because  it  will 
not  be  dissipating  much 
power. 

Once  you  have  the  safety 
requirements  for  these  regula- 
tors in  mind  and  know  how 
to  work  within  them,  there 


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are  several  tough  dog  prob- 
lems which  have  surprisingly 
simple  solutions. 

The  first,  and  most 
obvious  problem,  is  what  to 
do  when  you  need  to  supply 
more  than  one  Ampere  of 
current.  This  doesn't  often 
come  up  with  experimental 
circuits,  but  does  with  a  lot 
of  finished  equipment. 

The  technical  type  answer 
to  a  problem  like  this  would 
be  to  use  an  external  pass 
transistor  with  the  regulators 
as  the  controlling  element. 
The  transistor  can  handle  the 
extra  current,  but  it  makes 
for  a  more  complicated  cir- 
cuit. 

There  is  an  easy  way  out. 
Use  more  than  one  IC  regu- 
lator. Split  up  the  load  among 
several  so  that  no  one  has 
more  than  it  can  handle.  This 
is  shown  in  Fig.  9,  and  is 
quite  a  common  feature  of 
many  circuits.  It  also  provides 
better  decoupling  between 
different  parts  of  the  equip- 
ment. 

When  you  are  working 
with  experimental  circuits  it 
would  be  nice  to  have  a 
variety  of  voltages  available. 
A  multi-output  supply  is  a 
formidable  undertaking  .  . . 
or  is  it? 

That  same  technique  can 
be  used  to  provide  a  number 
of  standard  output  voltages. 
Fig.  10  shows  the  basic  sche- 
matic* The  resistance  values 
can  be  figured  the  same  way 
as  in  the  example  already 
given. 

One  thing  to  keep  in  mind 
is  that  the  total  output  cur- 
rent is  limited  by  the  output 
current  available  from  the 
basic  supply.  Thus  if  the 
supply  can  only  handle  three 
Amps,  then  you  cannot  draw 
more  than  that  in  total 
through  the  combined  regula- 


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tors. 

Fig.  1 1  shows  an  oddball 
circuit  that  I  was  told  would 
work  with  a  single  supply.  It 
does  not  look  like  something 
for  the  faint  of  heart. 

It  might  work,  but  it 
breaks  the  rules  about  not 
pushing  the  ratings.  While 
normal  operation  would 
divide  the  voltage  between 
the  two  so  that  each  was  only 
getting  a  few  volts  more  than 
needed  for  operation,  if  one 
regulator  were  to  short,  it 
might  throw  the  full  voltage 
to  the  other  regulator. 

As  this  is  on  the  dangerous 
side  of  the  ratings,  it  might 
damage    the    other  regulator 


loo.  It  doesn't  cost  that  much 
to  play  it  safe. 

That  should  handle  just 
about  any  of  the  usual  experi- 
mental or  finished  equipment 
regulated  supplies  you  might 
need  for  most  of  your  work. 

These  devices  are  probably 
the  most  commonly  available 
on  the  surplus  market,  but 
there  are  many  more  that  also 
can  be  used.  Some  are  in- 
tended for  more  precise  uses 
or  other  applications,  but 
most  can  be  used  just  the 
same  way  that  the  ones  men- 
lioned  can. 

A  quick  look  shows  that 
the  external  parts  used  are 
often  the  same  values  as  given 


for  the  devices  described. 

This  sort  of  information  is 
usually  supplied  with  the 
application  notes  for  the  IC 
It  would  pay  to  get  the  appli- 
cation notes  for  any  new  type 
you  were  not  already  familiar 
with. 

The  ICand  solid  state  field 
is  constantly  changing.  By  the 
time  this  is  in  print  there  may 
be  a  whole  new  line  of 
goodies  available  to  the  ex- 
perimenter on  the  surplus 
market. 

There  are  a  number  of 
small  regulators  that  will 
supply  standard  voltages  at 
one  or  two  hundred  mils. 
These  were  intended  for  on- 
board use  in  sections  of 
equipment  and  cost  less  than 


a  buck  each. 

One  item  that  is  expensive 
now,  but  may  come  down,  is 
the  three  terminal  high  cur- 
rent regulator  capable  of  five 
Amperes  of  current  or  so. 

Looking  at  the  ads,  there 
seem  to  be  a  number  of  smaJI 
kits  of  parts  and  built 
modules  that  will  supply 
sufficient  voltage  and  current 
for  both  digital  IC  and  op 
amp  type  ICs  for  a  price  close 
to  what  the  parts  would  cost. 
They  should  be  kept  in  mind 
as  a  quick  and  easy  way  into 
the  game. 

If  you  stick  to  the  simple, 
available  and  cheap  for  a 
while  and  remember  not  to 
push  the  ratings,,  it  will  be 
hard  to  go  wrong.  ■ 


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from  page  26 

one  and  one  half  year  YASME 
DXpedmon.  They  operated  as  VFUZ, 
VR8B,  3D2KG,  C21NI,  FK0KG  and 
YJ8KG.  (All  GSLs  via  YA3MEr  P.O, 
Bo*  2025,  Castro  Valley  CA  94546.1 

Iris  recently  applied  to  the  FCC  for 
a  two  letter  call  of  her  choice,  under 
the  new  rule  for  Extra  class  holder 
with  more  than  25  years  eaperience. 
Iris's  first  choice  was  W6QL  (W6GL 
was  formerly  held  by  Jim  Wells,  a 
famous  DXer,  now  a  si  ten  l  key).  So  it 
is  now  Lloyd,  "W6  King  George"  and 
tris,  "W6  Queen  Lady." 

Ins  and  Lloyd  hope  to  renew  their 
"Worldwide  YA5ME  DXpedition" 
again  to  some  different  parts  of  the 
world  in  a  few  months, 

Uoyd  Col vm  W6KG 
Iris  Col vin  W6QL 
Castro  Valley  CA 


*   t     *-i 


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si 


j         i 


YOUR  OWN  LEXICON 


May  I  suggest  that  somewhere  in  /3 


you  provide  a  column  similar  to  the 
Q$T  "Hints  and  Kinks"  column  but 
geared  specifically  to  "computronics," 
Le.,  the  computer  end  of  ham  radio. 
Oftentimes  there  are  little  tidbits  that 
we  come  across  while  putting  together 
a  computer  system  that  can  be  of 
great  help  to  others  who  may  end  up 
experiencing  the  same  difficulty.  Such 
little  trivia  as  taking  Elmer's  glue  and 
tacking  each  of  the  48  fiber  washers 
to  the  Imsai  22  slot  mother  board  can 
save  hours  of  time  in  trying  to  align 
each  to  its  respective  hole  and  also 
insure  thai  there  will  be  no  shorts  to 
chassis.  Such  helpful  hints  would  not 
warrant  a  full  length  article  and  yet 
they  are  important.  To  further 
illustrate,  if  one  wanted  to  purchase 
the  IMSAI  UCR1  cassette  I/O  board, 
it  would  be  nice  to  know  that  this 
board  is  not  a  "connect  the  plugs  and 
start  recording"  device.  Rather,  the 
board  requires  an  extensive  program 
to  be  entered,  which  takes  about  one 
hour  on  the  keyboard  and  about  three 
hours  loading  from  the  front  panel.  So 
unless  one  is  prepared  to  buy  an 
additional     ROM    or    PROM    board. 


there  will  be  lots  of  loading  to  do  each 
time  it  is  to  be  used.  On  the  othur 
hand,  the  National  Multiplex  Corpora- 
tion "CC7"  data  recorder  will  work  as 
a  stand  alone  device.  And,  too,  ii  will 
interface  with  current  ham  RTTY  gear 
such  as  a  model  28  or  a  deluxe  Hal 
Ds'3DQG\  We  also  have  this  recorder, 

Ten  months  and  almost  $2,700 
dollars  later  we  have  set  up  a  very  nice 
fully  operating  computer  system.  We 
have  experienced  the  good  and  the 
bad.  Generally  the  good  has  been  Hal 
Communications,  Godboui.  etc.  The 
bad  has  been  in  large  measure  due  to 
ignorance,  but  also  to  a  reluctance  on 
the  part  of  some  companies  to  share 
wtth  you  all  the  pertinent  informa- 
tion, Some  companies  such  as  God 
bout  and  Hal  will  go  out  of  their  way 
to  be  helpful  and  specific.  Others 
(nameless)  wiH  not  do  so,  which  puts 
one  in  a  precarious  position  if  he 
knows  not  what  to  ask. 

Perhaps  you  could  call  the  column 
Byte  Bugs,  Ins  and  Outs,  Bug  Bits  or 
just  ptam  Bugs.  Or  you  could  do  like 
Shakespeare  and  create  your  own 
lexicon.  Give  it  some  thought,  Wayne. 
There  are  a  lot  of  fellow  hams  out 
there  who  are  itching  to  jump  into 
computromes  and  whose  only  reluc- 
tance appears  to  be  a  lack  of  knowl- 
edge. Certainly,  one  can  hold  the  cost 
be  tow  that  of  a  good  transceiver  and 
still  have  a  fine  computer  controlled 
station  that  wiir  also  play  Star  Trek 
with  the  kids.  I  knowP  with  the  Hal 
Ds-3000  2.x  tied  into  the  company 


IBM  370,  the  IMSAI  8080  with  lots  of 
memory  and  a  host  of  I/O  cards  and 
keyboards,  I  could  provfde  lots  of 
helpful  hints. 

Nenad  S.  Downing  WB4SLG 
Chattanooga  TN 

Anyone  for  Ins  &  Outs?  —  Wayne. 


NUTS? 

I've  been  in  Taiwan,  a  polite  state 
incorrectly  described  as  *'an  outpost 
of  freedom,"  for  a  year,  I  read  and 
speak  Chinese  so  they  don't  foot  me 
(and  I've  got  an  MA  in  studying 
them).  You  cannot  believe  how 
fortunate  we  Americans  are  -  no 
secret  police,  no  political  slogans  on 
TV.  radio,  and  painted  on  every  wait, 
a  free  press,  policemen  who  help,  not 
spy,  and  on  and  on  and  on+  Of  course 
there  is  no  ham  radio  here,  save  for  a 
couple  of  showcases  in  Taipei. 

Add  my  compliments  to  S&D  Sales- 
I  ordered  one  of  their  cheap  clocks.  It 
arrived  ten  days  after  I  mailed  my 
order  and  works  perfectly,  Also  got 
simitar  service  on  a  CPO  ordered  from 
Heath. 

Also  pass  on  my  compliments  to 
the  folks  at  73,  I  sent  in  an  order  lot 
books  and  tapes  and  got  them  in  three 
weeks?  You  folks  must  be  nuts. 
Things  don't  work  like  that. 

Joseph  A.  Schlatter,  Jr.  K4FPT 
APO  San  Francisco  CA 


39 


Doit  Inman 

350  Nelson  Rd, 

Scotts  Valley   CA  95066 


Hamming  101 

-  -  another  Cabrillo  College 
pioneering  program 


Recently,  I  sat  in  on  two 
sessions  of  a  Cabrillo 
College  summer  school  CW 
group.  Cabrillo  is  a  com- 
munity college  located  in 
Aptos  CA.  The  CW  group  is  a 
part  of  ET  8QAB,  Special 
Projects  in  Electro nics,  which 


gives  an  opportunity  for  stu- 
dents to  explore  electronics 
areas  of  special  interest  on  an 
independent  study  or  seminar 
basis.  Forty  students  are 
enrolled  in  the  course; 
twenty-six  of  these  are  in  the 
CW  group. 


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Girls  participate  in  cfassf  too. 


Eddy  Pollock,  Director  of 
Technical  and  Vocational 
Education,  acts  as  the  ring- 
master for  this  three  ring 
circus  composed  of  beginners, 
advanced,  and  super  students. 
The  beginners  group,  at 
present,  has  ten  members 
receiving  and  sending  at  0  to 
4  wpm,  The  advanced  group 
has  twelve  working  at  6  to 
over  14  wpm.  The  super 
group  has  four  members 
qualifying  at  over  1 6  wpm. 
The  goal  of  each  student  is  to 
improve  his  code  speed  at 
least  one  word  per  minute  per 
week, 

Eddy  keeps  all  three 
groups  going  at  the  same  time 
in  adjoining  rooms.  A  normal 
classroom  serves  as  a  place  for 
instruction  and  code  practice. 
EnroHees  take  turns  on  the 
key   so    that   both   receiving 

and  sending  practice  are  pro- 
vided. An  adjoining  room 
houses  WB6JOD,  the  Cabrillo 
amateur  station.  Here  is 
where  the  real  action  takes 
place.  All  groups  have  a 
chance  to  get  in  on  "live" 
communications  at  the 
station  as  well  as  "canned'1 
tape  programs. 

No  doubt  some  73  readers 
are  aware  of,  or  have  com- 
municated with,  WB6JOD  or 
its  predecessor,  WA6TST. 
Eddy  established  WA6TST 
when  he  came  to  Cabrillo  in 
1960.  In  1962  Cabrillo 
moved  to  its  permanent  and 
present     location     and     was 


assigned  the  call  letters 
WB6JOD.  The  station  is  a 
part  of  the  Electronics  Tech- 
nology Communications 
Laboratory,  as  well  as  serving 
as  the  Tri-C  (Cabrillo  College 
Communications)  Electronics 
Club  station. 

Mr.  Pollock,  a  charter 
member  of  the  Institute  of 
Amateur  Radio  and  a  lifetime 
subscriber  to  73  Magazine,  is 
an  inspiration  to  past  and 
present  Cabrillo  electronics 
students.  Well  over  two 
hundred  students  have 
obtained  amateur  radio 
licenses  as  a  result  of  his 
efforts  with  the  Tri-C  Club* 
The  club  holds  practice 
sessions  at  noon  during  the 
regular  school  year  and  in  the 
evenings  during  the  summer. 
Tri-C  has  scored  high  or  won 
several  DX  and  Field  Day 
contests, 

WB6JOD  is  a  busy  station 
with  many  users.  It  operates 
up  to  30  hours  some  weeks, 
the  total  time  depending 
upon  the  number  of  per- 
sonnel available  for  super- 
vision. Contacts  have  been 
made  with  approximately 
150  foreign  countries  and  all 
states  in  this  country. 

Li  censed  personnel 
attached  to  Cabrillo  include: 
Eddy  Pollock  W6KHS,  First 
Class  Radio  Telephone  Engi- 
neer, Amateur  Extra  Class, 
and  Citizens  Band;  Dr.  Larry 
Edler  WB6MVK,  Extra  Class; 
Jim  Marshall  WA6HCL,  Ad- 
vanced Class;  George 
Jurichovich  K6PPZ,  General 
Class;  Royce  Krilanovich 
K6QJZ,  Advanced  Class, 
Adult  Evening  Program 
teacher;  Mary  Duf  field 
WA6KFA,  General  Class, 
Electronics  for  Young  People 
teacher, 

During  the  1976-77  school 
year  Cabrillo  will  add  specific 
seminars  for  radio,  ET  84AB 
will  prepare  students  for  an 
Advanced  Class  FCC  license, 
and  ET  84CD  offers  prepara- 
tion for  the  Extra  Class  FCC 
license. 

All  age  groups  and  both 
sexes  were  represented  in  the 
CW  class  this  summer.  Intense 
interest  was  highly  evident  in 
the  class  as  members  offered 


40 


constructive  criticism  and  en- 
couragement to  each  other's 
efforts.  This  attitude  seems  to 
pervade  the  amateur  hobby 
groups  with  which  I  have 
come  in  contact- 
Community  colleges,  such 
as  Cabrillo,  help  to  fill  a 
vacuum  that  is  being  created 
in  our  public  secondary 
school  systems.  As  school 
financing  gets  more  critical, 
special  interest  classes  such  as 
radio,  computer  program- 
ming, and  other  electronics 
courses  are  in  trouble.  As 
schools  become  more 
crowded,  the  administration 
begins  to  examine  the  smaller 
classes  for  possible  elimina- 
tion* A  teacher  is  thus  freed 
to  take  the  overload.  By  their 
very  nature,  laboratory 
classes  are  usually  small  due 
to  equipment  and  safety 
factors,  Therefore,  they 
become  the  prime  target  for 
elimination.  New  courses 
being  suggested  in  the  rapidly 
expanding  computer  field  are 
failing  to  get  off  the  ground 
for  the  same  reasons. 

Many  of  us  in  the  educa- 
tion field  feel  that  these 
classes  are  important  -  even 
more  important  than  some  of 
the  traditional  classes  which 
are  "  re  qui  red"  courses  for  all 
students.  We  must  find  ways 
to  provide  this  kind  of  knowl- 
edge to  our  young  people.  It 
is  in  this  area  that  community 
services  offered  by  such  com- 
munity colleges  as  Cabritlo 
prove  so  valuable. 

Another  aspect  of 
Cabrillo's  Community  Ser- 
vices was  opened  to  me  re- 
cently. My  12  year  old  son 
participated  this  past  year  in 
two  electronics  courses 
offered  to  youngsters.  One 
striking  feature  observed  was 
the  creation  of  a  soft-sell 
technique  for  education, 
Public  school  teachers,  as  well 
as  parents,  could  learn  some- 
thing from  this  approach.  No 
pressure  for  grades  and  no 
fact-memorization  to  pass 
tests  were  evident.  Each 
session  was  a  fun -111  led  and 
i  nf  ormation-packed  ex- 
perience.  From  the  surprise 
gift  package  of  electronic 
components,    which    opened 


Class  members  of  "Young  People  fs  Seminar  in  Electronic  Projects'*  at  work. 


the  first  meeting,  to  the  draw- 
ing for  electronics  books, 
which  closed  the  final 
meeting,  the  course  provided 
something  for  every  partici- 
pant. 

This  first  course  entitled 
"Electronics  for  Young 
People"  was  limited  to  10-14 
year  olds.  While  the  instruc- 
tor introduced  electronics  fun- 
damentals, the  students  were 
able  to  examine,  feel  and  ask 
questions  about  the  com- 
ponents under  discussion. 
Color  codes,  component 
units,  values,  etc.,  were  tied 
into  the  physical  components 
in  a  meaningful  way.  A  code 
oscillator,  a  frequency 
counter,  a  two  meter  trans- 
ceiver and  other  electronic 
"goodies"  received  lots  of 
attention  during  the  break  of 
the  three  hour  sessions. 

During  the  second  session 
of  this  course,  my  son  and  I 
contributed  a  computer 
demonstration.  An  Altair 
8800  with  IK  of  memory, 
operating  in  machine 
language,  was  used.  This 
equipment  is  part  of  a  system 
being  built  up  by  the  Moun- 
tain Digital  Group,  a  small 
local  organization  dedicated 
to  providing  the  schools  with 
an  introduction  to  computers 
and   computer  programming. 

While   a    brief  description 


of  the  computer's  operation 
was  being  given,  Kurt  pro- 
grammed the  computer.  He 
loaded  a  few  number  guessing 
games  for  the  students  to 
play.  (For  those  of  you  with 
new  computer  equipment  but 
no  input/output  devices  — 
lake  heart.  There  are  a 
number  of  interesting  things 
you  can  do  through  the  front 
panel  switches  with  only  a 
small  amount  of  memory.)  In 
Kurt's  first  number  guessing 
game,  a  correct  guess  trig- 
gered a  music  program  and 
"  Daisy "  was  played  over  a 
nearby  radio.  A  guess  too 
high  turned  on  all  the  data 
lights,  and  a  guess  too  low 
turned  off  all  the  data  fights. 
The  kids  really  went  for  this 
game.  There  were  many  "Far 
out!",  "How  neat",  and 
"Ah"  and  "Oh"  remarks 
from  the  young  audience. 

A  visit  to  Cabrillo's  ama- 
teur radio  station  highlighted 
the  final  meeting  of  the  class. 
On  one  wall  was  a  world  map 
with  a  pin  for  each  foreign 
contact  made  by  the  station, 
QSL  cards  were  posted  along* 
side  from  many  stations. 
Eddy  Pollock  fired  up  the 
transmitter,  and  each  student 
was  allowed  to  speak  into  the 
"live'  mike.  It  was  several 
minutes  before  each  student 
had   sent    the   sounds   of  his 


voice  over  the  airwaves*  Eddy 
then  spoke  a  few  words  into 
the  microphone,  and  sud- 
denly the  students  were  con- 
fronted by  the  sound  of  their 
own  voices  coming  back  over 
the  receiver.  It  seemed  that 
Eddy's  father,  Earle 
WA6Q5Q,  another  ham,  had 
recorded  the  students'  trans- 
mission and  was  now  playing 
it  back  from  his  own  trans- 
mitter. The  students  also 
visited  the  Radio  and  TV  Lab 
of  the  college  during  this 
session. 

During  class  breaks  and  at 
other  times,  Mary  Duffield 
WA6KFA,  the  instructor  of 
11  Electronics  for  Young 
People,"  tuned  in  her  trans- 
ceiver to  one  of  the  amateur 
bands.  While  students 
gathered  around,  Mary  ex- 
plained how  to  get  a  ham 
license  and  encouraged  all  to 
take  a  crack  at  it. 

Mary  recently  retired  from 
33  years  in  the  public 
schools.  Owner  of  a  35  foot 
sailing  vessel,  Mary  was  drawn 
to  the  field  of  radio  commun- 
ications out  of  necessity. 
Cabrillo  provided  her  with 
the  opportunity  to  learn  elec- 
tronics, and  she  now  holds  a 
General  Class  license.  She  has 
become  so  enthused  over 
amateur  radio  that  she  is  now 
thoroughly      involved     in 


41 


Members  of  Tri-C  Electronics  Club  at  the  Novice  station. 


passing  along  her  new-found 
knowledge  to  youngsters.  As 
I  write  this,  Mary  is  out  at  sea 
with  a  group  of  young 
people.  They  are  involved  in 
UNESCO  work,  contacting 
other  young  people  from 
other  countries.  They're 
making  friends  via  radio  com- 
munications and  face-to-face 
contact.  Her  summer  ex* 
perience  should  be  a  story 
unto  itself. 

Eddy  Pollock  is  the  real 
mover  behind  these  courses 
for  youngsters.  He  set  up  and 
taught  the  original  course  in 
1971  at  the  urging  of  Com- 
munity Services.  Twelve 
students  showed  up  for  the 
original  offering,  and  classes 
have  been  full  ever  since. 
Over  four  hundred  children 
have  poured  through 
Cabrillo's  doors  to  take  part 
in  this  one  course, 

A  natural  Follow-up  to  this 
introductory  class  was  one 
called  u  Electronic  Construc- 
tion" taught  by  Eddy  him- 
self. This  class  opens  with  a 
quick  review  of  the  previous 
course*  The  students  were 
then  given  a  handful  of  com- 
ponents and  a  printed  circuit 
board  in  order  to  learn  and 
practice  soldering  techniques. 
Enough  college  students,  who 
volunteered  as  lab  assistants, 
were  provided   for  almost  a 


one-to-one  ratio  of  super- 
visors to  students.  Recogni- 
tion of  components,  their 
characteristics,  and  methods 
of  mounting  on  printed 
circuit  boards  were  demon- 
strated and  practiced.  Correct 
usage  of  hand  tools,  with 
particular  stress  on  safety, 
was  brought  into  play. 

Students  were  allowed  to 
select  their  projects  from  a 
suggested  list  for  group  pur- 
chase or  to  select  one  of  their 
own  choosing  from  some 
other  source.  Quite  a  variety 
of  projects  were  chosen, 
including  code  oscillators, 
battery  checkers,  walkie- 
talkie  AM  radios,  three-band 
radios,  strobe  lights,  a  para- 
bolic microphone,  and  an 
infrared  burglar  alarm. 

At  the  second  session,  all 
kits  had  arrived.  An  air  of 
anxious  anticipation  filled  the 
room.  Before  construction 
began,  the  students  checked 
their  parts  lists  for  any 
omissions  or  incorrect  parts. 
They  were  then  on  their  own 
to  construct  their  kits  from 
the  assembly  manuals 
furnished.  There  was  much 
excitement  evident  as  boxes 
and  plastic  bags  full  of  com- 
ponents were  opened  and 
examined. 

"Is  this  a  capacitor?" 


"What  is  this?" 
"Look  at  your  parts  list." 
"Which  resistor  is  the  Ik?" 
14  Look     at     your     color 
code/1 

Questions  flew  faster  than 
the  assistants  could  respond, 
at  first.  What  an  ideal  learnmg 
environment!  Then  the  class 
settled  down  to  a  semi -quiet 
concentration  as  parts  began 
to  be  put  into  their  proper 
places. 


Two  class  meetings  were 
largely  devoted  to  actual  con- 
struction of  the  projects.  Lab 
assistants  provided  advice  and 
aid  when  troublesome  areas 
were  encountered.  Test  in- 
struments were  provided  to 
check  out  the  projects  at 
various  stages  of  completion. 
Happiness  and  satisfaction 
glowed  in  the  young  faces  as 
projects  checked  as  desired.  If 
the  results  were  not  satisfac- 
tory, a  grim  determination  to 
find  the  cause  and  set  things 
right  was  seen. 

At  the  fourth,  and  firtaf, 
meeting,  the  students  were 
allowed  some  lime  to  put 
final  touches  to  their  project. 
The  projects  were  then 
arranged  in  groups,  according 
to  the  age  of  the  builders. 
Each  student  then  inspected 
each  project  and  cast  a  vote 
for  the  best  constructed 
project  in  each  age  group. 
Students  voted  for  the  best 
overall  project,  also.  Each 
winner  received  a  prize,  either 
an  amateur  radio  book  or  a 
project  construction  book. 
The  grand  prize  winner  re- 
ceived a  walkie-talkie  con- 
struction project  as  well. 

The  future  of  amateur 
radio  and  other  hobby  groups 
seems  secure  as  long  as  people 
like  Mary  Duffield  and  Eddy 


Code  practice  even  during 
Projects  class  at  Cabrtllo. 


break  at  1976  summer  Special 


42 


Pollock  can  be  found.  But, 
they  need  help.  Look  around 
your  own  community  and  see 
if  such  courses  exist.  If  not, 
find  out  if  facilities  and  per- 
sonnel to  start  such  courses 
can  be  found.  Find  the 
persons  who  are  putting  their 
hearts,  as  well  as  their 
energies,  into  providing  for 
those  children  whose  educa- 
tion is  rapidly  approaching  a 
"no  frills11  condition.  Give 
them  some  of  your  time  and 
help  if  you  can. 

At  the  present  time,  most 


schools  feel  that  they  have 
neither  the  facilities  nor  the 
personnel  to  handle  programs 
of  this  nature.  They  also  have 
problems  scheduling  non- 
traditional  courses  in  an  over- 
crowded situation.  It  is  my 
contention  that  provision 
should  and  must  be  made. 
Certain  techniques  of  learning 
in  a  laboratory  environment 
are  vastly  superior  to  the 
lecture-test  methods  of  many 
traditional  classrooms. 

My     particular     field    of 
interest  is  in  computers,  and  I 


feel  very  disturbed  in  meeting 
strong  resistance  to  the  imple- 
mentation of  courses  in  this 
important  and  fast  growing 
field.  As  a  member  of  the 
Mountain  Digital  Group,  it 
has  been  my  privilege  to 
present  demonstrations  in  our 
local  intermediate  and  high 
schools,  as  welt  as  at  Cabrilto 
College.  We  also  presented  a 
session  at  the  California  State 
Science  Teachers  Convention 
in  an  effort  to  interest 
teachers  in  computer  kit- 
building    classes.     With    the 


appearance  of  inexpensive 
kits  spreading  at  a  rapid  pace, 
it  is  obvious  that  there  is  no 
reason  a  student  should  be 
denied  access  to  a  computer. 
Projects  carried  out  this 
past  year  in  my  own  class- 
room have  shown  that  high 
school  students,  with  little 
electronics  experience,  are 
capable  of  putting  together 
microprocessor  kits.  In  addi- 
tion, they  acquire  an  amazing 
amount  of  electronic  knowl- 
edge in  an  enjoyable,  infor- 
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at  the  second  IF.  *  800  Selectable  receive  frequencies.  ■  Accessory  9-pin 
socket.  *  S495.00 

TEMPO  SSB /ONE 

SSB  adapter  for  the  Tempo  VHF/One 

•  Selectable  upper  or  lower  sideband.  «  Plugs  directly  into  the  VHF/One  with 
no  modification.  •  Noise  blanker  built-in.  •  RIT  and  VXO  for  full  frequency 
coverage,  •  $225.00 


TEMPO  CL  246 A 

.  .  .a  VHP/ FM  mobile  tran- 
sceiver for  the  2  meter  amateur 
band.  It  is  compact,  ruggedly 
built  and  completely  solid  state. 
One  channel  supplied  plus  two 
channels  of  your  choice  FREE 

144  to  148  MHz  coverage  *  Multifrequency  spread  of  2  MHz  •  12  channel 
possible  •  Metering  of  output  and  receive  •  Internal  speaker,  dynamic 
microphone,  mounting  bracket  and  power  cord  supplied.  A  Tempo  "best 
buy"  at  $239.00. 


TEMPO  POCKET  RECEIVERS 

MS-2,  4  channel  scanning  receiver  for  VHF  high  band,  smallest  unit 
on  the  market.  MR -2,  same  size  as  MS- 2  but  has  manual  selection 
of  23  channels,  VHF  high  band.  MR-3,  miniature  2-channel  VHF 
high  band  monitor  or  paging  receiver.  MR-3U,  single  channel  on 
the  400  to  512  UHF  band.  All  are  low  priced,  extremely  compact 
and  dependable. 


[UK 


TEMPO 

100  ALIO 


SOLID  STATE  VHF  LINEAR  AMPLIFIER.  144  148  MHz.  Power  output 
of  100  watts  (nom)  with  only  10  watts  (nom)  in.  Reliable  and  compact 


9 


J  J  J   it  1.   I    1 


i  JtJ 


n 


TEMPO  imh 

So  much  for  so  little!  2 
watt  VHF/FM  hand  held 
6  Channel  capability,  solid 
State,  12  VDC.  144-148  MHz 
(any  two  MH2],  includes 
2  pair  of  crystals,  built-in 
charging  terminals  for  ni- 
cad  cells.  3-me1ert  battery 
level  meter,  telescoping 
whip  antenna,  internal 
speaker  &  microphone, 

$199.00 


TEMPO 
6N2 


The  Tempo  6N2  meets  the  demand  for  a 
high  power  six  meter  and  two  meter 
power  amplifier.  Using  a  pair  of  Eimac 
8874  tubes  it  provides  2000  watts  PEP 
input  on  SSB  and  1000  watts  input  on  CW 
and  FM,  Completely  self-contained  in 
one  small  desk  mount  cabinet  with 
internal  solid  state  power  supply,  built-in 
blower  and  RF  relative  power  indicator. 

$895  00 
The  Tempo  2002. .  2  meters  only  $745,00 
The  Tempo  2006. .  6  meters  only     $795.00 


TEMPO 

VHF/UHF  AMPLIFIERS 

Solid  state  power  amplifiers  for  use  in 
most  base/mobile  applications. 
Increase     the  range,  clarity,  reliability 
and  speed  of  two-  way  communications. 


Low   Band   VHF  amplifiers  available   in   100W  out  with 
2,  10  &  30W  in.  High  Band  VHF  amps  available  in  30,  50, 
80  Si  130W  out  with  2P  10  &  30W  in,  UHF  amps  available 
in  10,  25,  40  &  70W  out  with  1 H  2,  10  St  30W  in. 
Call  or  write  for  spec  sheet  and  prices. 


Most  of  the  above  products  are  available  at  dealers  throughout  the  U.S. 


i/emM/g 


11240  W.   Olympic  Blvd,.  Los  Angeles,  Calif,  90064   213/477*6701 
931    N.  Euclid,  Anaheim,  Calif.  92801  714/772-9200 

Butler,   Missouri   64730  Bt$/679-3127 

Prices  sublet  to  ;ir*flf*  m'houl  notice 


never  before  has  one  company  presented  such 
a  broad  selection  of  superb  amateur  equipment 


Kenwood 


TS-i 

.„!!»  "PACESETTER" 

Kenwood  has  a  trained  a 
hrgher  level  o*  achievement 
m  i{3  TS-820  than  ever 
reached  before  The  dis- 
criminating amateur  who 
wants  i he  very  Ciest  need  look  no  further  nor  wait  any  longer.  The  TS-B20 
Pacesetter"  will  provide  superior  performance,  versatility  and  features  found  In  no 
Other  transceiver  The  new  "Pacesetter"  is  the  ultimate  proof  of  Kenwood's 
dedication  to  offering  only  the  very  finest  possible,  $830.00  Dig  Hal  readout  (DG-1} 
$170,00 


Kenwood 
TS-520 


*■ 


A  no-com promise,  do  every- 
thing, 90  everywhere  5  band 
transceiver  for  SSB  or  CW 
thai  performs  equally  well  at 
home,  in  an  automobile,  air- 
plane, boat  or  trailer  The 
TS-52Q  features  built-tn  AC  power  supply,  buill-m  12  volt  DC  power  supply,  built-in 
VOX  with  adjustable  gain,  delay  and  anti-VOX.  plus  a  host  of  other  important  fea- 
tures and  proven  Kenwood  reliability.  Air  at  a  price  most  amateurs  can  afford.., 
S629  00 


YAESU 
FT-101E 


More  radio  from  the  radio 
company!  The  new  FT-iQiE 
includes  a  potent  R.F. 
speech  processor  and  easy- 
to-use  lever  switches.  A  more 
refined  ciarifier  control   for  *• 

pushbutton,  Independent  ciarifier  operation.  A  160  meter  Crystal  Js  Included  And 
all  the  other  features  that  have  made  the  FT-101  series  of  transceivers  among  the 
world's  most  popular  are  still  here;  260  watts  SSB  PEP  and  globe  circling  power  on 
CW  and  AM.  160  to  10  meters  range.  The  FT-101  E...S749, 00 


The 

TEMPO  ONE' 


The  Tempo  'ONE'  SSB  transceiver  represents  the  culminating  achieve* 
ment  of  many  years  of  experience  in  the  amateur  radio  field.  Modern 
design,  superb  performance,  sturdy  construction,  outstanding  reliability 
.  .  .  at  a  surprisingly  low  price  makes  the  Tempo  'ONE'  the  best  buy 
in  transceivers  today... S399. 00. 
AC/ONE  power  supply  ^S99.00    DC/1 -A  power  supply... $120.00 


Tempo  2020     ■ 


A  new  offering  by  Tempo  features  phase  lock* loop  (FLU  oscillator  circuit,  hybrid 
digital  frequency  display,  advance  solid-state  design  (only  3  tubes),  AC  and  12 
VDC  power  supply.  CW  filter,  noise  blanker.  VOX  and  semi-break  in  CW  keying,.. 
AL16UILTIN  All  amateur  bands  60  through  10  meters  M  1*1  n- mode  USB,  LSB.CW 
and  AM   Operation    $759.00 


The  2K-4 

LINEAR  AMPLIFIER 

The  2K-4  linear  amplifier  offers  en- 
gineering, construction  and  features 
second  to  none,  and  at  a  price  that 
makes  it  the  best  amplifier  value  ever 
offered  to  the  amateur.  Constructed 
with  a  rugged n ess  guaranteed  to  pro- 
vide a  long  life  of  reliable  service,  its 
heavy  duty  components  allow  it  to 
loaf  along  even  at  full  legal  power.  If 
you  want  to  put  that  strong  clear 
signal  on  the  air  that  you've  probably 
heard  from  other  2K  users,  now  is 
the  time.  Move  up  to  the  2K-4.   5995 

3K-A 

COMMERCIALmiLITAfiY  AMPLIFIER 


A  hlph  quality  linear  amplifier  designed  for  commercial  and  military  uses.  The 
3K-A  employs  two  rugged  Eimac  3-5002  grounded  grid  modes  for  superior  llneaniy 
and  provides  a  conservative  three  kilowatts  PEP  input  on  SSB  with  efficiencies  In 
the  range  of  60%.  This  results  m  PEP  output  in  excess  of  2000  watts.  In  addition, 
the  3K-A  provides  a  heavy  duty  power  supply  capable  of  furnishing  2000  watts  of 
continuous  duty  input  for  either  RTTV  or  CW  with  1200  watts  output.  Price... 
S1395.0U 

AKo  a  complete  Line  of  high  power  linear  amplifiers  for  commercial 
anil  military  use  and  industrial  power  generators  for  plasma  generation. 
Please  cell  or  write. 


TEMPO/FMH 

TEMPO/FMH2  watt  VHF/FM  hand  held.  6  channel 
capability,  solid  State,  12  VDC,  144-148  MHz  (any  2 
MHz),  includes  2  pair  of  crystals,  charging  terminals 
for  ni-cad  cells,  S-meter,  battery  level  meter.  So 
much  for  so  tittle*  Also  available  for  Commercial  & 
Marine  service. ..$199, 00 


TEMPO  VHF/UHF 
Power  amplifiers 

Power  amplifiers.  Solid  state  power 
amplifiers  for  use  in  most  land  mobile  applications.   In- 
creases the  range,  clarity,  reliability  and  speed  of  two-way 
communications.  FCC  type  accepted  models  also  available. 

Tempo  VHF/ONE 

Advanced  design  syntnesi^ed  2*  meter 
transceiver  Features  5-digil  LED  receive 
frequency  display  and  full  2-meter  band 
coverage  <14$  to  148  MH2K  automatic 
repealer  split,  all  solid-state.  10  watts 
xjtput  £495,     SSS  adapter 


TEMPO  CL146A 

VHF/FM  mobile  transceiver  for 
2  meter  amateur  band,  144  to  1 48 
MHz  coverage.  Compact,  ruggedly 
built  and  completely  solid  state. 
One  Channel  supplied,  ,  .2  of  your 
choice  f  ree...S239.00 

TEMPO 6N2 

Power  amplifier  For  6  and  2  meter  op  ation,  Small,  reliable  and  in- 
expensive. One  fuU  KvV  of  power  for  $$B  operation.  Features  two 
Ei mac  8874  grounded  grid  triodes,  built-in  solid  state  power  supply, 
built-in  antenna  relay. ..SB95.00. 

The  TEMPO  2002...  for  2  meters  only. .5745,00 
The  TEMPO  2006...  for  6  meters  only. .£795.00 

Please  come  in,  call  or  write  for  complete  information  on  any  of  the 
superb  products  listed. 


/ 


11240  W.  Olympic  Blvd.,  Los  Angeles,  Calif.  90064 
911  N.  Euclid,  Anaheim,  Calif,  92801 
Butler,  Missouri  £4730 


213/477-6701 
714/772-9200 
816/679-3127 


PrCA  Mtetf  St 


-:♦■:* 


-t- 


STAFT 


Ul 

7400 
CONTROL 


60Hi— • 


I8WPW 


CLOCK 
PULSES 


U3 
7493 
BINARY 
ADDRESS 


CONTROLS  ft  RESETS  COUNTERS 
TO  ZERO 


STOP  CONTROL  AT 
END  OF  MESSAGE 


PULSE 
EVERY 
16  PULSES 


U5 
7493 
BINARY 
ADDRESS 


J—f 


Bert  Kelley  K4EEU 
2307  S.  Clark  Ave. 
Tampa   FL  33609 


KEYING 
TRANSJSTORS 
02TQ3 


CODE   CHARACTER  OUTPUT 


jjti     FOR  KEYING  POSITIVE 
VOLTAGES 


TO  n 


FOR  KEYtWG  NEGATIVE 
VOLTAGES 


Q>\LY  7  OF 
16  OUTPUTS 
SHOWN- 


■Ml  54 


6   U4 


J 


DIODE  "KEY  DOWN 


y 


-O  +5V 


s 


k 


^ 


U7 

MONITOR 
OSCILLATOR 


Fig,  1.  Block  diagram  of  CW  fDer. 


\ 


ETC. 


Super  Cheapo  CW  IDer 

-  -  for  FM  repeaters  and  RTTY 


Side  view  of  board  showing  construction  of  matrix. 


This  device  automatically 
generates  your  call 
letters  for  the  FCC  required 
CW  identification  and  can  be 
started  by  either  a  push- 
button or  a  pulse  from  other 
equipment.  If  you  have  been 
hand  sending  CW  or  using  a 
mechanical  code  wheel  on 
RTTY,  here  is  a  way  to 
improve  operation  at  low 
cost.  It  also  has  an  audio 
output  that  can  be  used  as  a 
monitor  or  to  modulate  FM 
repeaters. 

The  IDer  is  complete  on  a 
small  4*'  x  6"  circuit  board 
with  built-in  power  supplyl 
provision  for  either  positive 
or  negative  voltage  keying 
without  relays,  monitor,  and 
an  adequate  128-bit  diode 
memory.  Its  simple  design  is 
its  best  feature  because  the 
TTL  logic  required  is  cheap 
and  available.  The  diode 
memory  is  easily  programmed 
or,  if  necessary,  changed 
when  needed.  Contrast  this 
with  more  sophisticated 
designs  using  programmable 
ROMs  which  must  be  pro- 
grammed correctly  the  first 
time  with  no  mistakes.  The 
code  speed  Is  derived  from 
the  ac  line  for  a  fixed  18 
wpm.  This  eliminates  a  few 
parts,  and  adjustment,  but 
fully  complies  with  regulation 
97.87(h).  Last,  but  equally 
important,  a  circuit  board  is 
available  to  help  you  in  con- 
struction. 


46 


Circuit 

The  block  diagram  (Fig,  1} 
shows  the  functions  of  the 
integrated  circuits.  U1  is  a 
start/stop  control  and  resets 
U2,  U3  and  U5  so  they  start 
each  sequence  from  the  same 
point.  A  push-button  or  pulse 
sets  U1,  the  control  line  goes 
low,  and  U2  starts  dividing  60 
Hz  pulses  by  four,  driving  U3. 
The  BCD  output  of  U3  deter- 
mines the  status  of  U4,  a  four 
line  to  sixteen  line  decoder/ 
multiplexer  —  actually  a  sort 
of  single  pole,  16  position 
rotary  switch.  As  U3  counts, 
U4  advances  and  grounds 
each  of  the  sixteen  outputs  in 
sequence.    In    the   meantime, 

U5  is  counting  each  time  U4 
finishes  a  complete  sweep, 
and  with  U6  is  used  to  select 
the  eight  output  lines  A 
through  H,  so  that  only  one  is 
active  for  each  sweep  of  U4. 
This  multiplies  the  16  posi- 
tion output  of  U4  by  a  factor 
of  eight,  giving  a  matrix  with 
a  128  position  or  Hbit" 
capacity.  When  U6  has  com- 
pleted its  sequence,  U5  gen- 
erates a  pulse  which  auto- 
matically resets  U1,  and  con- 
cludes the  transmission. 

The  eight  input  lines  to  U6 
are  pulled  to  a  logic  one  by 
2200  Ohm  resistors  mounted 
vertically  on  the  circuit 
board.  The  inverted  output  of 
U6  then  remains  low  and  the 
keying  transistors  are  inactive 
unless  the  scanning  sequence 
is  started  and  reaches  points 
in  the  matrix  where  diodes 
are  connected.  They  allow  U4 
to  ground  inputs  of  U6 
without  short-circuiting  all 
the  connections  together.  If 
we  assume  the  IDer  is  at  rest, 
pin  1  of  U4  is  grounded,  and 
the  input  line  A  of  U6  is 
positive  via  the  2200  Ohm 
resistor.  Since  this  is  the  at 
rest  or  starting  point,  no 
output  Is  wanted  and  there- 
fore this  position  has  been 
omitted     from     the     circuit 

board  layout,  When  the 
button  is  pressed,  the  matrix 
Is  scanned  from  the  resting 
point  A0  through  A1,  A2, 
etc.,  to  A15,  then  B0,  B1 ,  B2, 
etc.,  until  operation  con- 
cludes at  HI 5.  Viewing  the 
trail  side  of  the  circuit  board, 


it  is  in  reverse  to  the  way  you 
read  a  paragraph  in  a  maga- 
zine. The  schematic  {Fig.  2) 
shows  an  example  of  the  IDer 
as  programmed  for  "DE 
K4EEU/' 

Q2  and  Q3  are  high 
voltage  keying  transistors.  If 
you  are  keying  a  positive 
voltage,  only  Q2  is  installed. 
For  negative  keying,  add  03 
and    a    Ik    base    resistor    as 


Front  view  of  CW  IDer. 

shown.  Naturally,  Q2  can  be 
used  to  operate  a  relay  if  you 
want  to  key  an  isolated 
voltage  in  a  B  plus  line,  for 
example. 

Monitor 

The  555  timer  makes  a 
simple  and  effective  monitor. 
The  frequency  will  be  about 
800  Hz  with  components 
shown,  a  square  wave  which 


is  more  than  adequate  to 
drive  a  small  speaker  directly. 
The  tone  is  all  right  for  moni- 
toring but  may  be  cleaned  up 
with  a  simple  low  pass  filter. 

Parts  and  Construction 

A  circuit  board  layout  is 
given  In  Fig,  3  for  those  who 
want  to  make  their  own.  An 
epoxy,  undrilted,  but  plated 
circuit  board  with  parts  list  is 


AH  parts  mounted  on  board.  Note  ample  reserve  space  in  diode  matrix. 


47 


*5VO 


START 


-VWHt   2ZOOfl{a) 


FUSED  I  IT  VAC       h 


\A     13      12      II       ID      J       6       7       6      ■■       4        3       ?        | 

KEYING  OUTPUT 
POSIT I VE  OH  NEGATIVE  VOLTAGES 

EPTiO 


Ll^F 
^        ^WSC  DISC 


SPEAKER 


*5V 


Fig.  Z  Schematic  of  CW  IDer  programmed  for  "DE  K4EEU,  " 


Fig.  3.  PC  board. 


available  from  me  for  $8 
postpaid  US  and  Canada 
only.  Parts  locations  are 
screened  on  the  board  to 
make  construction  fast  and 
easy. 

The  HEP  transistors  are 
shown  because  they  are 
stocked  by  many  local  parts 
houses  as  universal  replace- 
ments. RCA  has  a  similar  line 
and  SK-3018,  SK-3103,  and 
SK-3025  may  be  substituted 
for  Q1,  Q2  and  Q3.  The 
remaining  parts  are  sold  by 
advertisers   in  this  magazine. 

Note  that  the  mounting 
screws  on  the  LM309K  regu- 
lator are  also  circuit  connec- 
tions, and  verify  that  the 
regulator  output  is  5  V  within 
a  few  tenths  of  a  volt,  Diodes 
may  be  either  silicon  or 
germanium,  but  should  be 
checked  on  an  ohm  meter. 
They  are  mounted  vertically 
with  cathode  band  toward 
the  circuit  board. 

The  speaker  impedance  is 
not  critical.  Once  the  holes 
are  drilled  with  a  #60  drill  all 
parts  can  be  mounted  on  the 
circuit  board  and  the  unit 
bench-tested  in  about  one 
hour,  The  completed  device 
can  be  installed  in  a  small  5" 
x7"  x3"  chassis  or  mounted 
in  vacant  space  in  other 
equipment  such  as  a  RTTY 
demodulator. 

Programming 

This  is  done  by  installing 
diodes  at  locations  where  a 
tone  is  wanted  on  the  matrix 
according  to  the  following 
rules:  The  first  bit,  A0,  is 
reserved  for  standby.  A  dash 
is  three  bits,  or  three  diodes 
in  a  row;  a  dot  is  one  bit,  or 
one  diode;  a  space  is  one  bit, 
or  no  diode.  Three  vacant 
spaces  between  characters, 
and  seven  bits  or  vacant 
spaces  between  words.  An 
L-shaped  bus  is  formed  of 
stiff"  plated  wire  and  con- 
nected above  the  board 
between  each  A,  B,  Cp  D,  E, 
F,  G,  H  input  of  U6  and 
supported  at  the  other  end 
above  the  board  by  the 
vertical  2200  Ohm  resistor. 
The  anodes  of  the  vertically 
mounted  diodes  are  soldered 
to  these  buses.  ■ 


43 


FACTORY  DIRECT  ONLY" 


1 


WILSON  204  MONOBANDER  PLUS  DB33 


REAL 
MONO 

PERFORMANCE 

ON 

10-15-20 


The  Wilson  204  is  the  best  and  most  economical 
antenna  of  its  type  on  the  market.  Four  elements  on  a 
26  boom  with  Gamma  Match  (Wo  balun  required) 
make  for  high  performance  on  CW  &  phone  across  the 
entire  20  meter  band. 


The  204  Monobander  is  built  rugged  at  the  high  stress 
points  yet  using  taper  swaged  slotted  tubing  permits 
larger  diameter  tubing  where  it  counts,  for  maximum 
strength  with  minimum  wind  loading.  Wind  toad  99.8 
lbs.  at  80  MPH.  Surface  area  3,9  sq.  ft.,  Weight  50  lbs,. 
Booms  2"  OD, 


All    Wilson    Monoband   and   Duoband   beams   have   the   following   common    features: 


Taper  Swaged  Tubing 
Full  Compression  Clamps 
No  Holes  Drilled  in  Elements 
2"  or  3"  Aluminum  Booms 


•  Adjustable  Gamma  Match  52  £2 

•  Quality  Aluminum 

•  Handle  4kw 

•  Heavy  Extruded  Element  to  Boom  Mounts 


SPECIAL  on 
Wilson  Hand  Held  220  and  450 


2202  SM 

FREQUENCY  RANGE  220  ■  225  MHz 


•  6  Channel  Operation 

•  Individual  Trimmer t  ort  all  TX/fiX  Cryitalf 

•  All  CryitalSi  Plug  In 

■  12  KM;  Ceramic  Filter 
-   10  7  ind  455  KC  IF 

■  .1  Microvolt  Senutmty  For  20  dB  Quitting 
«  Weight    I  lb.  14  &j\  let*  Battery 

■  03 iter/  indicator 

•  Size    M/Ixl   3/4  *  2  7/8 

•  S wit cfi able  1  it  2.5  Watts  Output 
9  ir  voc 

■  Current  Drain-    RX    14  MA,  TX   500   MA 

•  Micro iwilch  Mike  Button 

•  Unbreakable  Lexan  -   Cat* 


USES  SAME  ACCESSORIES  AS  1405 

XlliaS  SPECIAL 

'219.K 

INCLUDES 

1.2202SM 

2.  Flex  Antenna 

3.  223.50  Simplex  Installed 


4502  SM 

FREQUENCY  RANGE  420  ■  450  MHz 


•  £  Channel  Operation 

■  individual  Trimmer!  on  all  TX/flX  Cryitalt 

•  All  Crystal*  Plug  In 

•  12  KHz  Ceramic  Filter 

•  214  and  4S5    KC   IF 

•  .3  Mtcrotfolt  Sensitivity  for  20  dB  Quieling 

•  weight    1  lb-  14  oz    Jess  Battery 

•  Biltery  Indicator 

•  Si*e:  *  7/*  m  I   3/4  H  2  7/1 

•  Sw^chable  |  &    \-t  Watti  Output 
•  12  VDC 

•  Current  Drain:  RX    14  MA.   TX   500  MA 

■  Micitjvwitch  Mike  Button 

•  Unbreakable  Lexan  I   Caie 


USES  SAME  ACCESSORIES  AS  1405 

XITiaS  SPECIAL 

'269.W 

INCLUDES 
1.  4502  SM 

2.  Flex  Antenna 

3*  446,00  Simplex  Installed 


ACCESSORY  SPECIALS 


SPEC  1 AL 
DESCRIPTION                                PRICE 

BCI 

BATTERY  CHARGER 

13*  95 

BP1 

Id  EA.  A  A  COULD 
H1CAD  BATTERIES.  . 

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50 


Have  you  been  in  search 
of  an  antenna  with 
gain,  directivity  which  you 
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verified. 

The  antenna  consists  of 
two  equal  triangular  loops 
e^g'1  in  overall  length.  Both 
are  coupled  very  closely  by 
passing  the  loop  of  the  driven 
side  through  the  undriven 
side,  as  shown  in  the  diagram 
at  B. 

The  support  boom  can  be 
made  from  any  type  of 
material:  wood,  bamboo, 
aluminum,  PVC  tubing. 
Nylon  fishline  was  used  for 
guying. 

How  does  tt  work?  Fan- 
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The  ZF  Special  Antenna 


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On  10,  15,  and  20  meters, 
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The  antenna  I  am 
presently  using  has  4  ele- 
ments at  right  angles  to  each 
other,  with  all  the  vertical 
elements  connected  to  the 
center  conductor  of  the  coax 
and  all  the  horizontal 
portions  connected  to  the 
braid.  Needless  to  say,  the 
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all  bands.  * 


--  double -D  "beam" 


Fig.  1. 


20  t\.  SUPPORT  BOOM 


IflSULATCW 


75  OHM 

COAX 


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51 


n^ 


W.  J.  Prudhomme  WB5DEP 
1405  Rictilmd  Avenue 
Metaiiie  LA   70001 


CT700I  Clockbuster 


-  -  the  ultimate  clock/calendar 

(for  now) 


be  described  in  complete 
detail  later  in  the  article.  The 
integrated  circuit  makes  use 
of  a  60  Hz  timebase  fre- 
quency from  the  power  line 
to  count  the  hours,  minutes 
and  seconds.  There  are  also 
provisions  for  battery  backup 
should  the  power  line  fail, 
and  the  integrated  circuit  has 
its  own  internal  oscillator  to 
take  over  the  60  Hz  timebase. 
The  actual  frequency  is  deter- 
mined by  the  RC  circuit  con- 
nected to  pins  25  and  26  of 
the  integrated  circuit.  There 
are  no  particularly  critical 
parts  of  the  external  circuitry 
with  the  exception  that  you 
should  use  an  integrated 
circuit  socket  rather  than 
soldering  the  IC  directly  into 
the  circuit  The  reason  for 
this  is  that  the  MOS  type 
circuit  is  sensitive  to  static 
electricity  which  could 
destroy  some  of  its  inputs. 


For  several  months,  1 
have  been  toying  with 
the  idea  of  building  a  digital 
clock  using  one  of  the  many 
integrated  circuits  that  are 
out  on  the  market  today  (see 
the  ads  in  this  magazine),  A 
recent  sale  on  the  Cal-Tex 
CT7001  clock-on-a-chip  inte- 
grated circuit  was  too  much 
to  resist.  I  quickly  ordered 
one  along  with  six  readouts 
and  was  soon  on  my  way  to 


ACC  OUT  — 

ALARM  - 

IN  2 

IN  I 

IN  1 

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AM 
PM 


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2fi 
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£6 

CT7Q0I  25 

(TOP)  2* 
23 

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20 

IS 

10 

17 


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ftscour 

60H1  N 

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constructing  a  digital  clock. 
The  results  of  using  the 
CT7001  have  exceeded  my 
expectations,  and  this  article 
is  an  attempt  to  provide  you 
with  sufficient  information  to 
build  your  own. 

The  CT7001  has  many 
features  which  may  be 
selected  according  to  how  the 
various  scanned  inputs  are 
connected  to  the  digit  output 
pins.  The  chip  is  also  available 


in  either  seven  segment  out- 
puts  (CT7Q01)  or  BCD 
outputs  (CT7002). 

General  Description 

Fig.  1  is  a  block  diagram 
of  the  integrated  circuit  and 
external  connections.  All  that 
is  necessary  to  make  use  of 
the  Integrated  circuit  is  a 
power  supply,  4  or  6  read- 
outs, and  the  external 
switching   matrix   which  will 


Dl         D2i 


0  3       P4 


DS       D6 


AKDEFQ 


.1     I 


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I     i 


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IS  17  IS  IS  19  SOS        q  9 


l_l 

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10         ii 


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25 


26 


23 


24  £7 


C  T   7001 


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4 
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(4 

13 


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VSS 


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SUPPLf 


ACCESSORY 
OUT 


ACC ESS CRT 
CIRCUIT 


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|N5 


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SWSTCHENG 
MATRIX 


ALARM 
OUT 


ALARM 

CIRCUIT 


Fig,  L  Block  diagram  of  CT7001. 


The  particular  mode  of 
operation  is  determined  by 
connecting  various  digit  out- 
puts to  the  three  scanned 
inputs  of  INI ,  2  and  3,  The 
chip  was  designed  so  that 
setting  any  one  particular 
counter  such  as  the  time, 
alarm,  calendar,  etc.,  is 
possible  without  upsetting  or 
affecting  the  contents  of  any 
other  counter. 

Since  there  are  so  many 
options  available  with  the 
CT7001,  I  have  not  made  this 
a  detailed  construction 
article^  but  rather  a  descrip- 
tion of  how  to  apply  the 
CT7001  and  by  so  doing, 
allow  you  to  choose  the 
options  you  desire  in  con- 
structing the  digital  clock. 
This  way,  it  will  be  possible 
to  tailor  the  external  circuits 
according  to  your  own  in- 
dividual requirements. 

The  integrated  circuit  will 
accommodate  4  tn  6  seven 
segment  displays  as  shown  on 
the  block  diagram.  It  will 
direct  drive  luminescent  anode 
display  tubes,  and  the  applica- 
tion brochure  from  the  manu- 
facturer states  that  it.  will 
direct  drive  common  cathode 
LEDs,  However,  one  word  of 
caution    is  in   order.    It   will 


52 


direct  drive  common  cathode 
LEDs  as  long  as  the  segment 
current  does  not  exceed  five 
milliamps.  If  your  particular 
LED  will  draw  more  than  five 
milliamps  per  segment,  it  will 
be  necessary  for  you  to  incor- 
porate either  the  transistor 
driver  or  integrated  circuit 
driver  that  will  be  described 
later  in  the  article. 

To  summarize,  the 
CT7001  incorporates  a 
28/30/31  day  calendar,  12/24 
hour  clock  operation  with 
true  24  hour  alarm  setting, 
snooze  alarm,  50  or  60  Hz 
timebase,  6  digit  direct  drive 
display,  clock  radio  features, 
on  chip  60  Hz  backup  oscil- 
lator and  easily  settabfe 
counters  which  will  be  ex- 
plained in  the  following 
section. 

Operational  Modes  and 
Switching  Matrix 

Referring  to  Fig.  2,  we 
have  a  chart  showing  the 
scanned  input  options  which 
are  available  with  the  clock. 
The  first  input  is  INI  and  by 
connecting  various  digit  out- 
put pins  to  this  INI,  the 
operational  mode  of  the 
clock  will  be  changed 
accordingly.  Likewise,  the 
same  holds  true  for  inputs 
IN2and  IN3, 

For  example,  there  are 
three  display  modes  available, 
depending  on  the  connection 
of  IN3  to  either  D3  or  D4. 
With  no  connections  to  the 
CI  or  C2  inputs,  the  time  will 


be  displayed  for  eight  seconds 
and  the  calendar  for  two 
seconds.  If  the  C2  input  is 
closed  (D4  to  IN3),  only  the 
calendar  will  be  displayed  on 
a  continuous  basis.  Likewise, 
if  the  C1  input  is  closed  (D3 
to  IN3),  only  the  time  will  be 
displayed  on  a  continuous 
basis.  The  am  and  pm  outputs 
will  operate  during  the  clock 
and  alarm  display  modes 
when  the  clock  is  operating 
on  a  12  hour  basis.  If  it  is 
switched  over  to  a  24  hour 
clocks  the  am  and  pm  outputs 
will  not  be  available. 

This    means    that    if    the 
12/24   hour   input  is  closed 


Input  Pin 

Scan  Time 

Input  Name 

Def  in  it  ion,  Con  ne  ct  io  n 

INI 

D1 

Set 

Set  Counter 

IN1 

D2 

Set  H/M 

Set  Hour  or  Month  Digit 

IN1 

D3 

Cfock  Radio  Switch 

Clock  Radio  Switch  -  On 

IN1 

D4 

Mode  A 

Mode  A  -  Off 

IN1 

D5 

Mode  B 

Mode  8  -  On 

IN1 

D6 

50/60  Hz 

50  Hz  Input 

IN2 

D1 

Set  Calendar 

Set  Calendar  Counter 

IN2 

D2 

Set  Clock 

Set  Clock.  Counter 

IN2 

D3 

Set  Alarm 

Set  Alarm  Counter 

IN2 

05 

Set  Clock  Radio 

Set  Clock  Radio  Counter 

JN2 

D6 

Snooze  Switch 

Snooze  Switch  -  On 

IIM3 

D1 

Alarm  Switch 

Alarm  Switch  -  On 

IN3 

D2 

12/24  Hour 

24-Hour  Operation 

IN3 

D3 

CI 

See  note  beJow 

IN3 

D4 

C2 

See  note  below 

Front  view. 

(D2  to  |N3),  the  clock  will 
operate  on  a  24  hour  basis 
(00:00:00  to  23:59:59}. 
Should  the  12/24  hour  input 
be  opened,  the  clock  will 
display  12  hours  with  an  am 
and  pm  indication  both  on 
the  clock  display  and  the 
alarm. 

If  the  alarm  switch  is 
turned  on  {D1  to  IN3),  the 
alarm  output  will  go  high 
when  the  clock  counter  is 
coincident  with  the  preset 
alarm  counter.  The  alarm  out- 
put will  remain  high  until  it  is 
terminated  by  opening  the 
alarm  switch. 

While   the   alarm   is   func- 


Oef  inition.  No  Connection 

Set  Minute  or  Day  Digit 
Clock  Radio  Switch  -  Off 
Mode  A  -  On 
Mode  B  -  Off 
60  Hz  Input 


Snooze  Switch  -  Off 

Alarm  Switch  ■  Off 
12-Hour  Operation 
See  note  be  tow 
See  note  below 


Fig.  2.  Scanned  Input  Options.  There  are  three  display  modes:  (J)  If  the  CI  and  C2  inputs  are 
left  unconnected,  time  wit!  be  displayed  for  8  seconds  and  the  calendar  displayed  for  2  seconds; 
(2)  If  the  CJ  input  is  closed  (C2  open),  the  time  will  he  displayed  on  a  continuous  basis;  (3)  If 
the  C2  input  is  closed  (CJ  open),  the  calendar  will  he  displayed  continuously. 


tioning,  if  the  snooze  switch 
is  closed  momentarily  (D6  to 
IIM2),  the  alarm  will  be 
disabled  for  ten  minutes  and 
this  cycle  can  be  repeated  as 
many  times  as  desired  until 
the  alarm  is  disabled  by 
opening  the  alarm  switch. 

There  is  also  a  counter 
built  into  the  clock  chip  that 
can  be  set  in  one  minute 
increments  from  9  hours  and 
59  minutes  to  1  minute.  This 
feature  can  be  used  to  control 
some  external  appliance  and 
may  be  utilized  in  three 
different  ways  depending  on 
the  setting  of  the  Mode  A  and 
Mode  B  switches. 

When  Modes  A  and  B  are 
off,  the  accessory  output  will 
then  be  high  for  the  preset 
time  by  closing  the  accessory 
switch,  and  this  timed  cycle 

can  be  interrupted  at  any 
time  by  opening  the  switch. 
When  the  accessory  switch  is 
closed  again,  the  countdown 
will  continue  where  it  left 
off. 

If  Mode  A  is  on  and  Mode 
B  is  off,  the  accessory  will  go 
high  for  the  preset  time 
period  and  also  go  high  at  the 
alarm  time,  providing  the 
accessory  switch  is  on+  This 
mode  may  be  used  to  turn  & 
sleep/learning  tape  off  auto- 
matically and  then  wake  you 
up  at  the  preset  alarm  time. 


53 


— m 


The  third  possibility  is  to 
have   both    Mode   A   and   B 

turned  on  with  the  accessory 
switch  on.  This  will  allow  the 
accessory  output  to  go  high 
for  the  preset  time  only  at 
the  alarm  lime.  This  function 
may  be  used  to  turn  an  ex- 
ternal appliance  on  for  a 
certain  length  of  time  at  any 
desired   time.  The  individual 


counters  are  very  easy  to  set 
with  this  particular  integrated 
circuit  and  the  procedure  is  as 
follows: 

The  counter  to  be  set  is 
selected  by  closing  the  set 
calendar  clock  alarm  or  acces- 
sory switch,  which  is  accom- 
plished by  connecting  either 
Dl,  D2,  D3  or  D5  respec- 
tively to  the  IN2  input.  Then, 


VSS 


VDD 


2N2222A 


BLU7) 


{SEGMENT  DRIVER 
SEVEN  REQUIRED - 
SEGMENT7*    SHOWN! 


\  Bl  cl  el  El  Fl  Gl 


(I)  D1GJT 
SHOWM 


if  D2  is  connected  to  INI t  the 
hours  or  month  digit  will  be 
advanced.  Or  if  D2  is  not 
connected  to  INI,  the  minute 
or  day  digit  will  be  seL  Once 
this  is  determined,  connecting 
Dl  to  IN1  advances  the  digits 
of  that  particular  counter  at 
the  rate  of  one  digit  per 
second.  During  the  set  clock 
function,  connecting  Dl  to 
INI  also  sets  the  seconds  to 
zero  and  freezes  this  particu- 
lar register  until  the  clock  is 
started  again.  This  allows  you 
to  set  the  time  say  one 
minute  ahead  of  WWV  time, 
wait  for  the  tone,  then  switch 
the  function  switch  to  run  at 
the  right   moment,  With  this 


ZHZ2ZZA 

{DIGIT  DRIVER 
SIX  REQUIRED- 
DJ  ONLY  SHOWN! 


feature,  it's  a  cinch  to 
synchronize  the  clock  with 
WWV, 

The  calendar  display  for 
this  particular  integrated  cir- 
cuit is  very  unique.  It  has  an 
internal  memory  which  can 
determine  which  months  have 
28,  30  or  31  days.  It  will 
count  the  correct  number  of 
days  for  each  month  and 
advance  lo  the  next  month  at 
the  end  of  the  last  day  of  the 
previous  month.  The  only 
day  which  has  to  be  manually 
set  is  February  29,  This 
means  that  once  the  calendar 
is  set,  it  will  only  have  to  be 
reset  once  every  leap  year  on 
February  29.  When  I  think  of 
all  the  times  I  have  had  to 
manually  reset  the  calendar 
on  my  calendar  watch,  this 
one  feature  is  well  worth  the 
price  of  the  chip. 

Typical  Circuits 

Now  to  discuss  some 
actual  circuits  you  can  use  to 
build  a  digital  clock.  It  is 
possible  to  incorporate  either 
common  cathode  or  common 
anode  LEDs  in  the  display. 
As  mentioned  previously, 
direct  driving  of  the  LED 
segments  can  only  be  used  if 
the  particular  LED  that  you 
are  using  Is  a  common 
cathode  with  a  current  draw 
of  five  milliamps  per  segment 
or  less.  Figs,  3  and  4  show  a 
typical  application  for  tran- 
sistor driving  common 
cathode  and  common  anode 
LEDs,   Six   digit  driver  tran- 


DI5PLAV5  ARE   OLTO4  OR  EQUIVALENT 

HRS/UOS     MLWS  J  DAYS  5EC5 

Or        D£  DJ      B4  08       DG 


Fig,  3,   LED  interface  for  common  cathode.  RL  is  sized  to 
limit  current  for  specific  LED  used. 


im 


ZHZ22 


voe 


VDD 


PUT  ORiVtR 
SIX  ftlOUtRED- 
Dl  ONLY  5HOHNI 


ISEGWEHT  DRIVER 
El  .l*.  REQumtD- 
SEGUt^  ~l~  SriC*v: 


Fig.  4.  LED  interface  for  common  anode.  RL  is  sized  to  limit 
current  for  specific  LED  used. 


Fig.  5.  Improved  LED  interface  using  SN75491  and  SN? 5492 
integrated  circuits  (for  common  cathode  LED).  SN75491  — 
quad  segment  driver;  SN75492  -  hex  digit  driver,  Notes:  fl) 
For  both  SN75491  segment  drivers,  pins  3y  5,  10  and  12  are 
connected  to  pin  1  /  through  150  Ohm  %  W  resistor.  (2)  Vss  " 
7iAto9  VdcflO  Vdcmax). 


54 


yHfaoduceb 

(\  211  PL  L  SVN1HESIZER  Si  Advanced  All  So  Versatile/^ 


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Specifications 
RF  Output 30  Watts 

Infinite  VSWR  proof 

Sensitivity 0.3u  v720dB  Qt. 

Selectivity   -6dB  @  ±6.5  kHz. 

~58dBP±15  kHz; 

-90dB@  ±30  kHz. 
Desense /Over load  ...  W/luV  de- 
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55 


fCKGlT  DRIVER  DETAlLS-QQjpuj 
I  ALT  VO 


VDD 


COMMON  CATHODE  LED'S 

TO* 


ALL  fHWLSiHL  l*iSU 


[2  6  VAC 

eoHtiHiHjrr 


VDD 


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TO  Tp 

F3SORY      ALARM 
CtRCUIt  CIRCUIT 


, gftLJACCE^^Ht 


F/g.  6.  Typical  clock  circuit  for  common  cathode  readouts.  Note:  Each  of  the  SN7549J 
segment  drivers  has  pins  3,  5,  JO  and  12  connected  to  pin  1 1  through  a  ISO  Ohm  14  W  resistor. 
*Choose  RL  to  limit  LED  current  to  fess  than  5  mA  (typically  2  7k). 


sistors  are  required  as  well  as 
seven  individual  segment 
drivers.  Since  the  displays  are 
multiplexed,  all  segments  in 
ihe  display  are  wired  in 
parallel.  This  greatly  reduces 
the  number  of  drivers  and 
load  resistors  that  are  re- 
quired in  a  typical  circuit. 

1 1  is  also  possible  to  use 
integrated  circuit  drivers  for 
the  digits,  which  greatly  re- 
duces  the  amount  of  external 
wiring.    Fig.    5    indicates    an 


improved  LED  interface  using 
SN75491  and  SN75492  inte- 
grated circuits.  This  diagram 
is  for  a  common  cathode 
installation.  The  SN75492  is 
a  hex  digit  driver  and  the  two 
SN7  5491s  are  quad  segment 
drivers.  For  both  of  the 
SN75491  segment  drivers, 
pins  3,  5t  10  and  12  are 
connected  to  pin  11  through 
a  150  Ohm,  lA  Watt  resistor. 
The  application  sheet  on  both 
these  integrated  circuits  indi- 


cated that  the  maximum 
supply  voltage  is  ten  volts  and 
it  is  probably  better  to 
operate  them  between  TVS  to 
9  volts  dc  to  avoid  any 
damage  to  ihe  integrated  cir- 
cuits. 

In  my  particular  clock,  I 
had  already  etched  the  circuit 
board  before  I  realized  that  it 
would  be  possible  to  use  the 
improved  interface  integrated 
circuits.  Consequently,  my 
particular  clock  is  a  hybrid, 


using  six  transistor  digit 
drivers  and  two  SN75491 
quad  segment  drivers  as  a 
typical  application.  This  is 
shown  in  Fig.  6  and  inciden- 
tally, this  diagram  is  a  typical 
application  which  allows  you 
to  incorporate  all  the  func- 
tions that  are  available  within 
the   clock   integrated  circuit. 

In  order  to  keep  the  front 
panel  of  the  clock  as  simple 
as  possible,  I  located  the 
display  select,  12/24  hour, 
Mode  A  and  Mode  B  switches 
on  the  rear  apron  of  the 
clock*  The  set/function 
switch,  the  set  counter,  and 
the  hours/minutes  selector 
along  with  the  accessory  and 
alarm  switches  were  located 
on  the  front  panel  of  the 
clock,  I  used  LEDs  of 
different  colors  to  indicate 
the  am  and  pm  settings  of  the 
clock  and  also  an  LED  for 
each  of  the  accessory  and 
alarm  switches  to  indicate 
when  these  switches  were 
turned  on.  This  feature  helps 
to  remind  you  to  turn  off  the 
alarm  or  accessory  when  you 
don't  want  to  be  awakened 
early  on  a  Saturday  morning. 

There  are  various  options 
in  regard  to  the  alarm  circuit, 
and  Fig.  7  shows  a  typical 
alarm  circuit  using  a  tran- 
sistor driver  interface  to  turn 
on  a  programmable  unijunc- 
tion transistor  oscillator 
driving  an  internal  8  Ohm 
speaker.  A  potentiometer  can 
be  incorporated  into  the 
circuit  to  vary  ihe  lone  of  the 
alarm  output  to  suit  your 
own  particular  preference. 
The  output  from  this  oscil- 
lator is  sufficient  to  awaken 
all  but  the  most  ardent 
sleeper. 

A  friend  of  mine  included 
another  unijunction  in  his 
clock  to  produce  an  alarm 
similar  to  a  police  siren.  How* 
ever,  the  side  effects  the 
wavering  alarm  tone  had  on 
his  wife  prompted  him  to 
quickly  change  the  circuit 
back  to  a  steady,  soothing 
tone, 

A  transistor  driver  circuit, 
similar  to  the  one  used  to 
turn  on  the  alarm,  can  be 
used  to  operate  a  12  volt  dc 
relay.  The  contacts  from  this 


56 


relay  can  be  used  to  control 
some  type  of  accessory  func- 
tion such  as  a  clock  radio, 
lamp  or  appliance.  In  my 
particular  installation,  I  am 
using  it  to  switch  1 20  volts  ac 
to  an  accessory  socket  at  the 
rear  of  the  clock  which  is 
used  to  turn  on  a  small  radio. 
However,  it  can  also  be  used 
to  turn  on  some  external 
appliance  or  other  similar 
(unction.  The  circuit  diagram 
is  shown  in  Fig.  8. 

Various  power  supply 
options  are  available 
depending  on  your  own 
personal  requirements  and 
the  amount  of  regulation  that 
is  desired.  Fig.  9  shows  a 
typical  power  supply  with  a 
PNP  power  transistor  used  to 
help  regulate  the  output  for 
the  unit.  Battery  backup  is 
provided  by  two  nine  volt 
batteries  installed  with  a  six 
volt  zener  diode.  CR2  is  in- 
stalled to  prevent  the  battery 
from  supplying  power  to  the 
displays  when  the  normal 
power  has  failed.  The  battery 
is  only  used  to  operate  the 
integrated  circuit  with  its  on- 
board oscillator  to  keep  the 
clock  functioning  during  a 
power  failure.  A  variation  to 
this  circuit  may  be  used  to 
display  the  time  for  short 
periods  to  conserve  battery 
power.  Simply  connect  a 
momentary,     N.  O.     SPST 


push-button  switch  across 
CR2.  This  will  allow  you  to 
bypass  the  diode  to  display 
the  time. 

In  some  cases,  it  may  be 
objectionable  for  the  leading 
zero  to  be  displayed  during 
clock  operation  and  also 
during  calendar  display,  it  is 
possible  to  blank  the  leading 
zero  by  means  of  a  transistor 
and  a  few  resistors.  Since 
segment  F  is  the  only  seg- 
ment not  required  to  form 
the  digits  one  or  two,  it  can 


Top  view,  showing  alarm  speaker 

be  used  to  uniquely  describe 
zero.  If  segment  F  is  present 
during  D1  time,  the 
2N2222A  transistor  will  turn 


off  the  Dl  to  the  display 
while  preserving  the  Dl  signal 
to  the  input  matrix.  Fig.  10  is 
taken  from  a  Cal-Tcx  applica- 


TO  60  Hi 

rNPUT 

\\ 


13  VDC 

UNREQ 

ii 


C-R3 
IN  4001 

-H— 


l£.6VAC 
300  mA 


ffi 


TO 

DISPLAYS 
4 


1-IEVOC] 
VDD 


'50M  F 
"35  V 


VSS 


■  1 i  VDC 


FROM 
ALARM 


FREQUENCY 
ADJUST 

/ 


OUTPUT 
(P3N  3  1 


. — *wv 


Fig.  9.  Power  supply  for  the  CT700J  clock.  During  normal 
operation,  all  power  Is  supplied  from  the  ac  power  supply. 
During  a  power  failure,  the  clock  continues  to  operate  from 
the  battery  backup  composed  of  two  9  volt  batteries.  To  limit 
current  drain  on  the  batteriest  a  diode  blocks  power  to  the 
displays.  A  push-button  bypass  switch  across  diode  CR2  may 
be  installed  to  momentarily  view  the  display, 


VOD 


1TD  DISPLAY  DRIVER) 


Fig,    Z  PUT  =  programmable  unijunction  transistor  (Radio 
Shack  276- i  19  or  equivalent). 


+ 12  VDC 


FflOto 

ACCESSORY 
OUTPUT    -w» f 


2N2222A 


(PIN  2)         4.7K 


c 


=bjcJ-  — -*£ 


K.I 


ITO 
/ACCESSORY 


22K 


i 

SF  TO  INPUT 

<TQD>5PLA*      OFMATfll* 
DRIVER1 


Fig,  8,  K1  =  12  V  dc  coil  relay  suitable  for  switching  accessory 
loads  for  miniature  size. 


Fig.  10.  Zero  suppressing  the  Dl  digit.  Since  segment  F  is  the 
only  segment  not  required  to  form  digits  1  or  2,  It  can  be  used 
to  uniquely  describe  ft  If  segment  F  is  present  during  Dl  time, 
the  2N2222  A  will  turn  off  the  Dl  to  the  display,  white 
preserving  the  Di  signal  to  the  Input  matrix. 


57 


lion  note  on  how  the  circuit 
should  be  connected  to  zero 
suppress    the    leading    zero. 

Since  I  have  not  incorporated 
this  feature  in  my  particular 
clock,  I  can't  vouch  for  the 
values  of  the  resistors  to  be 
used,  bul  I  assume  that  they 
are  the  normal  values  that  are 
used  in  the  other  driver  tran- 
sistor circuits.  You  might  try 
a  4.7k  resistor  for  the  base 
and  a  22k  resistor  for  the  bias 
resistor. 


Rear  view. 

For  those  of  you  who 
desire  more  accuracy  than  the 
power  line  regulation,  or  for 
that  matter,  high  accuracy 
when  the  power  line  fails,  it  is 
possible  to  incorporate  a 
crystal  oscillator  as  an  ex- 
ternal timebase.  This  is  shown 
in  Fig.  11  using  a  100.800 
kHz  crystal  with  a  one 
megohm  resistor  and  a  5-50 
pF  variable  capacitor.  The 
frequency  can  be  trimmed 
with  the  variable  capacitor  to 


result  in  a  very  stable  external 
timebase  whose  accuracy  is  a 
function  of  the  crystal  used. 

Conclusion 

The  clock  has  been  in 
operation  for  several  weeks 
now  using  only  the  timebase 
from  the  power  line  fre- 
quency to  determine  the 
accuracy  of  the  clock.  This 
timebase  has  proven  to  be 
adequate  for  most  operations. 


In  checking  lis  accuracy  in 
reference  to  WWV  lime 
signal,  I  have  only  noticed  a 
few  seconds  variation  over  a 
couple  of  weeks.  This  high 
accuracy  is  due  to  the  fact 
that  the  power  line  frequency 
is  corrected  from  time  to 
time  so  that  its  average  devia- 
tion cancels  out.  As  a  result, 
the  power  line  is  a  reliable 
source  for  a  60  Hz  timebase, 
barring  momentary  power 
lapses.  When  this  happens, 
the  chip  displays  one  more 
feature  —  at  the  moment 
power  is  restored,  the  clock 
begins  counting,  but  displays 
ail  8s.  This  is  to  let  you  know 
that  the  count  is  not 
accurate.  By  momentarily 
closing  the  set  counter 
switch,  the  clock  display  will 
appear.  Keep  this  in  mind  the 
first  time  your  clock  is  turned 
on,  as  all  8s  is  a  normal 
indication  until  the  set 
counter  switch  is  closed. 

In  closing,  I  highly  recom- 
mend the  CT7001  digital 
clock/calendar  IC,  and  should 
you  decide  to  build  your  own 
digital  clock,  it's  a  good  idea 
to  obtain  the  basic  applica- 
tion notes  from  Cat-Tex 
Semiconductor  along  with 
the  supplementary  applica- 
tion notes  listed  in  the  refer- 
ences. ■ 


\  M£0 
I/4W 


PIN  EE 


CT  TO  01 


HMZ5  (CfSC  OUT) 


CRYSTAL-  lOOflOOKHl 


Fig,  Ih  External  timebase.  In 
necessary  to  connect  the  60  Hz 
ANfflQ7). 


this  mode  of  operation,  it  is 
input  (pin  23)  to  Vss  (Cal-Tex 


References 

(1)  CT7Q01  Digital  Clock/Calendar  Circuit,  October,  1973 

(2)  Supplementary  information  on  CT7001  —  dated  January,  1975, 

(3)  AN#I08  -  Display  oscillator. 

(4)  AN#103  -  LEO  interface  for  common  anode. 

(5)  AN #102  -  Display  options* 

(6)  AMNIOS  -  Colon  blanking  during  calendar. 

(7)  AN^rl07  —  External  nmebase. 

AH  references  listed  are  available  from;   Cat-Tex  Semiconductor,  inc., 
3090  Alfred  Street,  Santa  Clara  CA  95050. 


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59 


The  Transceiver 

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—  such  things  as  individual  temperature  compensated  integrated  circuit  voltage  regulators  for  final  bias  control 
and  VFO  supply.  And  toroid  inductances  in  the  ten  and  fifteen  meter  low  pass  filters,  LED  indicators  for  offset 
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EXPORT:  5715  LINCOLN  AVE 
CHICAGO.  ILLINOIS.  60646 


60 


Since  1969,  the  year  in  which  TEN-TEC  introduced 
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Thent  in  1972,  a  break-through  —  the  100  watt  "405" 
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The  harsh  jangling  of  the 
phone  grabbed  me  by 
the  eardrums,  and  cruelly 
vibrated  me  awake.  Slowlyr 
groggily,  I  fumbled  at  the 
bedside  phone,  resolving  to 
leave  it  off  the  hook  the  next 
Friday  night.  It  seemed  that  I 
had  just  dropped  off  to  sleep, 
and  a  quick  look  at  the  clock 
confirmed  that  impression;  it 
was  9  am,  and  I  had  turned 
the  rig  off  only  three  hours 
ago.  Trying  to  work  Australia 
with  my  minimal  antenna 
system  was  as  fruitless  as 
hunting  with  a  water  pistol  — 
all  night  and  no  luck. 

The  phone  had  reached 
my  ear  by  now,  and  I 
mumbled  something  into  the 
mouthpiece.  "Good  morning, 
Karl!"  said  an  all  too  awake 
and  cheerful  voice,  '*!  just 
passed  my  Advanced  exam 
and  I  wanted  you  to  know/' 

"Ken,  are  you  kidding  me? 
You  just  got  your  General 
three  weeks  ago!"  Now 
completely  awake,  I  found 
this  news  to  be  both  amazing 
and  just  a  little  embarrassing 
—  this  kid  had  done  in  six 
months  what  had  taken  me 
three  years  to  do. 

"Well,  Karl,  I  had  a  day 
off  from  school t  and  I  have 
been  studying  for  at  least  two 
weeks  now,  so   I  decided  to 


give  it  a  try/'  He  decided  to 
give  it  a  try,  I  thought;  no 

denying  that  the  kid  had 
plenty  on  the  bail. 

"Well  that's  just  great,  it's 
fantastic,  actually,  I  gave  you 
your  Novice  not  more  than 
six  months  ago.  Congratu- 
lations! Not  many  hams  can 
beat  that;  not  bad  for  a 
converted  CBer." 

He  signed  off  and  I  turned 
over  in  bed,  not  to  sleep,  but 
to  think  on  his  brief  career  in 
ham  radio,  which  had  been 
nothing  short  of  astounding,  I 
felt  more  than  a  little  satis- 
faction   and   pride.    He   had 

done  the  work,  of  course,  but 
I  had  been  lucky  enough  to 
provide  the  proper  guidance 
and  to  help  send  him  on  his 
way. 

It  had  started  one  evening, 
while  listening  on  the 
Chicken  Band  (our  local  nick- 
name for  CB).  Amid  the  usual 
strange  chit  chat  and  madeup 
calls,  something  had  aroused 
my  interest.  There,  he  was 
back  again,  "Yes,  Little 
Chicken,  and  Red  Hen,  this  is 
KBC  1234  (I  can't  remember 
the  exact  call).  I  was  just 
saying  that  CB  is  OK  for 
some  things,  but  everything 
I've  heard  about  ham  radio 
makes  me  think  that  it's  a  lot 
more    fun,    and    interesting 


too."  I  couldn't  agree  more,  I 
thought;  let's  hear  more.  "All 
the  things  IVe  heard  about  it 
sound  real  neat,  like  talking 
to  other  count  ries,  using 
Morse  code  —  I  still 
remember  that  from  the 
Scouts  —  and  even  building  or 
fixing  your  own  gear.  You 
can  use  hundreds  of  Watts 
and  not  worry  about  the 
FCC.  It  sounds  like  a  great 
hobby,  but  it's  hard  to  get 
started,  1  sure  wish  I  had 
someone  to  help  me  out,  It's 
like  the  difference  between 
flying  a  kite  and  flying  an 
airplane/'  Not  a  bad  analysis, 
and  he  was  right.  CB  does 
have  its  worthwhile  uses,  if 
the  legitimate  stations  can  get 
out  from  under  the 
cacaphony  of  QRM  from  all 
those  "Little  Chickens"  on 
the  band. 

I  broke  in,  using  WSEWF's 
CB  call  and  rig  (which  I  had 
been  testing),  and  asked  him 
to  drop  over  to  my  shack  that 
afternoon,  to  get  that  help  he 
was  looking  for.  Expressing 
surprise  and  thanks,  the 
young  man  said  his  name  was 
Ken  and  that  he  lived  just 
around  the  corner  from  my 
house.  That  was  my  first  and 
last  CB  contact,  for  that  rig 
was  sold  the  next  day, 
W5EWF  having  despaired  of 


the  way  the  band  had 
developed  since  its  early  days. 
That  one  contact  made  for  a 
happy  result,  however:  the 
addition  of  a  bright,  talented 
and  very  enthusiastic  new 
ham  to  our  fraternity. 

Ken  was  right  on  time  for 
our  first  meeting,  and  1 
quizzed  him  on  his  back- 
ground, so  1  would  know 
where  to  start.  As  it  turned 
out,  he  had  a  good  start, 
having  retained  all  of  his  Boy 
Scout  Morse  code  (at  a  speed 
of  about  two  words  a 
minute),  and  having  studied 
basic  electronics  in  high 
school.  All  he  needed  was 
exposure  to  actual  ham  radio, 
as  well  as  guidance  in  his 
studies.  He  went  off  clutching 
copies  of  "How  To  Become  A 
Radio  Amateur"  and  MThe 
Radio  Amateur's  License 
Manual,11  not  to  mention 
several  copies  of  73,  An  hour 
of  twenty  meter  phone 
seasoned  with  the  forty  meter 
Novice  band  had  whetted  his 
appetite. 

Before  I  knew  it,  I  was 
giving  Ken  his  Novice  test. 
Naturally,  he  was  nervous, 
and  he  wrote  hunched  over 
the  forms,  in  intense 
concentration.  After  it  was 
over,  I  could  not  help  but 
notice  that  the  answers 
(which  I  had  accidentally 
seen)  were  all  correct. 
Although  I  reassured  him, 
Ken  was  anxiously  waiting 
for  the  mailman  for  the  next 
month  or  so,  calling  me  up 
every  other  day  (after  three 
weeks  had  gone  by), 
wondering  if  such  a  long 
delay  was  normal 

Then  one  day,  Ken  came 
running  up  as  I  shoveled  snow 

in  my  driveway.  Giving  the 
last  shovelful  a  heave,  I 
straightened  up  and  greeted 
him. 

Ml  made  it!"  he  shouted. 
'Tm  a  Novice,  Pm  a  ham!" 

"That's  great,  Ken  —  but  I 
knew  you'd  make  it.  What's 
your  call?'1  I  wondered  how 
far  down  the  list  they  had 
gotten, 

"I'm  WN9QDL!" 


62 


-Well,  WN9QDL,  why 
don1!  you  hustle  on  over  to 
your  QRP  Heath  rig  and  I'll 
work  you,"  Snow  shoveling 
really  never  excited  me  that 
much  any  way,  I  thought,  as  I 
headed  for  the  shack. 

One  thing  led  to  another, 
and  one  day  about  mid- April, 
the  new  Novice  became  a  new 
Technician,  and  then  (after 
borrowing  some  of  my  code 

tapes  and  a  Mule  technical 
advice    on     theory    and     its 

practical  application),  guess 
who  was  a  General?  I  was 
only  a  little  bit  surprised  at 

that,  for  Ken  had  been 
working  hard.  We  put  up 
some  improved  antennas  and 
I  loaned  him  my  rig  so  he 
could  try  phone  for  a  while, 
and  got  almost  daily  landline 
reports  on  how  he  was  doing. 
It  seemed  to  me  that  the 
thrill  of  being  off  the  limited 
Novice  bands  would  kind  of 
slow  down  the  climb  up 
through  the  license  grades, 
while  he  concentrated  on 
making  lots  of  contacts.  Well, 
I    was   sure   wrong  on    that 


score.  His  radio  library  had 
been  steadily  expanding  to 
the  point  that  I  was 
sometimes  borrowing  books 
from  him,  and  they  were  all 
well  used  when  I  received 
them  -  he  had  been  studying, 
So  now  Ken  was  an 
Advanced  class  ham.  As  I  got 
dressed,  I  counted  the 
months  since  he  had  received 
his  first  call  -  six  months,  to 
the  day.  Perhaps  there  were 
more  good  potential  hams 
marking  time  on  CB;  a  little 
encouragement  might  be  all 
that  would  be  needed  to  find 
them  and  bring  them  into  the 
hobby.  I  resolved  to  listen  in 
on  27  MHz  some  more.  Just 
then,  the  telephone  rang 
again,  interrupting  my 
thoughts.  It  was  Ken  a^in, 
asking  to  borrow  my  21  wpm 
73  code  practice  tape;  he  said 
he's  just  started  working  on 
his  amateur  Extra  and  his 
records  only  go  to  18. 
Hmmmr  I  wonder  if  he  can 
help  me  with  my  code  - 
maybe  I'll  get  that  Extra  class 
myself!" 


MORE  RANGE 


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The  radio 


KENWOOD'S 


Kenwood's  well  deserved  reputation  for  fine  craftsman- 
ship and  superb  performance  has  never  been  more  evi- 
dent than  in  the  TS-820*  As  a  result  of  a  host  of  innov- 
ative features  being  brought  together,  the  820  offers  a 
degree  of  versatility,  performance  and  pleasure  second 
to  none. 


The  Kenwood  TS-820  is  destined  to  be  the  world's  new 
standard  of  excellence  in  amateur  radio  for  years  to 
come  , .  .  a  true  "Pacesetter' 


Built-in  monitor 
cuit   allows  you  to  hear  your  own 
voice   by  sampling  the   RF   signal 
Especially  useful  for  adjusting  the 
RF  Processor 

The  TS-820  uses 
an  efficient  noise  blanker  circi 
another  Kenwood  exclusive  A  spe- 
cial crystal  fiher  assures  unsurpassed 
efficiency  in  eliminating  unwanted 
pulse  noises 

VFO-  82G 

The  VFO-820        -olid  state  remote  VFO  designed  exclusively  for 
use  with  the  Kenwood  TS-820  setter.  The  VFO-820  has  rrs 

Own  RJTcircuit  and  cr  i  fully  compatible  with  v 

optional  digital  disp  TS-820  The  perfect  extra  to  any 

Pacese 


A  single  pushbutton 
ritch  offers  the  operator  unprece- 
dented versatility  The  digital  hold 
circuit  will  lock  the  counter  and  dis- 
play at  any  frequency,  but  wilt  allow 
the  VFO  to  tune  normally.  Ever 
wanted  to  return  to  a  certain  spot 
on  the  band  and  forgotten  the  fre- 
quency? That  won't  happen  again 
with  the  new  digital  hold  feature  on 
the  Kenwood  TS  820, 

An  MF 
circuit  provides  quick  time  constant 
compression  using  a  true  RF  co 
pressor  as  opposed  to  an  iF  clippe 
Amount  of  compression  is  adjustable 
to  the  desired  level  by  a  convenient 
front  panel  control- 


The  IF  SHIFT  control 
ies  the  IF  passband  without  changing 
the  receive  frequency  This'lFshifi* 
control  is  located  on  the  front  panel 
and  provides  excellent  unwanted  sig- 
nal reject  control  or  pass  band  lim- 
ing '  The  820  moves  the  signal  across 
the  IF  pass  band  not  the  pass  ban 
across  the  signal. 


Nt  Easy,  one  touc 

activation  of  the  attenuatot  supplies 
20  dB  of  padding  on  receive. 

A  voice- activated  microphone 
s  built  into  the  TS  820  with 
VOX  GAIN.  ANTIVOX,  and  VOX  DE- 
LAY controls  placed  on  the  front 
panel  for  convenient  adjustment  any 
ie. 


■ 


eat  u  res 


160  METERS  •  Full  band  coverage 

Pi  employs  the  latest 

phase  lock  loop  circuitry  The  single 
conversion  receiver  section  perfor 
manct  offers  superb  protection 
against  unwanted  cross  rnodulaiio 
And  now  PLL  allows  the  frequency 
to  remain  the  same  when  switching 
sidebands  (USB.  LSB  CW)  and  elim- 
inates having  to  recalibrate  each  time. 

R{  The  I. 

earity  of  the  TS  820*s  final  amplifier 
stage  is  now  one  of  the  best  on  tf 
air  Third  order  inter  modulation  prod- 
ucts are  35  db  or  greater  below  the 
output  signal.  RF  Negative  Feedback 
from  the  PA  plate  circuit  to  the  driver 
cathode  permits  a  high  degree  of  lin- 
earity at  the  high  power  level  of  the 
final  tubes 

During  receive. 
an  easy  to  read  meter  functions  as 
an  S-meter,  The  same  meter  displays 
ALC  level  plate  current.  RF  outpt 
and  plate  voltage  during  transm 
Includes  COMP  setting  for  adjusting 
the  compression  level  of  the  built-in 
speech  processo 

The  TS  820 
completely  solid  state  except  for  the 
driver  (12BY7A)  and  the  final  tube 
Rather    than   substitute  TV  sweep 
tubes  as  final  amplifier   inb-  a 

state  of  the  art  amateur  transceiver 
Kenwood  has  employed  tw  sky 

S-2001 A  (equivalent  to  6146B)  tubes. 
These  rugged,  time-proven  tubes  are 
known  for  their  long  life  and  superb 
linearity  The  input  power  of  the  TS 
820  is  conservatively  rated  at  160  W 
DC,  200  W  PEP  Tubes  run  cool  with 
the  aid  of  a  noiseless  fan  (standard) 
mounted  on  the  rear  pa  ■  he  above 

tube  and  power  combination  mini 
mizes  the  possibilities  of  TVI   and 
helps  to  maintain  the  Kenwood  rep- 
utation for  excellent  audio  quality 

it  READ*  optional) 

A  digital  counter  display  can  bn  e- 
ployed  as  an  integral  part  of  the  VFO 
readout  system.  Counter  mixes  the 
carrier.  VFO,  and  first  heterodyne 
frequencies  to  give  uxact  frequency 
Figures  the  frequency  down  to  10  Hz 
and  digital  display  reads  out  to  100 
Hz.  Both  receive  and  transmit  fre- 
quencies are  displayed  in  easy  to 
read.  Kenwood  Blue  digits 

ncludes  the  same  satin 
smooth   planetary  drive   found   on 
other  fine  Kenwood  mo  plus  spa* 

ctal.  high-pre  gears  to  add  a 

new  "monoscale  f  feature  for  easier 
frequency  readout  LSB,  USB,  and 
CW  operating  frequencies  can  be 
accurately  read  from  the  same  po* 

The  filaments  of 
nree  vacuum  tubes  may  be  turned 
off  during  periods  of  "receive  only 


During  CW  reception,  a  special  filter 
is  used  to  aiter  the  audio  frequency 
response  to  provide  a  more  comfort- 
able  easy  to  copy  tone 

he  VFO. 
heart  of  any  SSB  transceiver,  is  an 
exclusive  Kenwood  design  using  FET 
technology 

Other  features  include: 

•  Built-in  25  kHz  calibrator* 

•  Built-tn  speakc 

•  CW  Stdetone  and  semi-break 

•  Rear  panel  terminals  for  linear 
amplifier   IF  OUT,  RTTY.  and  XVTR 

•  Handy  phone  patch  IN  and  OUT 
terminals 


Che  TS  -  5SO 

Why  wa>t  any  longer  for  a  ng  that  offers  top  performance,  depend- 
ability and  versatility  the  TS-520  has  proven  itself  in  the  shacks 
of  thousands  of  discriminating  amateurs  in  field  day  sites,  in  DX 
and  contest  stations,  and  m  countless  mobile  installations 
Superb  craftsmanship  is  evident  throughout  rn  its  engineering 
concepts  as  well  as  its  construction  and  styling  craftsmanship 
that  is  a  Kenwood  hallmark 
Maybe  the  Kenwood  TS-520  is  the  one  you  have  been  waiting  for 


t/te oeceteeftteb 


(mjjsptmt& 


///e  wYk/Mt/y  i 


The  SP-5  20  is  an  external  speaker  designed  for  use 
with  the  Kenwood  TS-520  The  SP-520  can  be  used 
in  place  of  the  tranceivers  built-in  speaker  for  better 
readability,  The  speaker's  cabinet  matches  the  TS-520 
from  panel  to  provide  a  clean  looking  integrated  station. 


The  VF0-520  is  a  solid  state  remote  VFO  designed  to 
match  the  TS-520  perfectly.  It  allows  VFO  controlled 
cross  channel  operation  when  connected  to  the  trans- 
ceiver A  built-m  RIT  circuit,  with  an  LED  indicator, 
permits  receiver  incremental  tuning. 

TV-502 

The  TV- 5  02  trans  verier  puts  you  on  2-meters  the  easy 
way  Simply  plug  it  in  and  you're  on  the  air.  Operates 
in  the  144.0*145.7  MHz  frequency  range  with  a  145  0- 
146  0  MHz  option.  TheTV-502  is  completely  compat- 
ible with  the  TS-520  and  the  TS-820 


KENWOOD'S 


'm/t± 


Kenwood  developed  theT-599D  transmitter  and  R-599D-rr.      /er  for  the  most 

discriminating  amateur 

The  R-599D  is  the  most  complete  receiver  ever  offered-  It  is  entirely  solid-state. 

superbly  reliable  and  compart    It  t         rs  the  full  amateur  band,  10  through 

160  meters   CW  LSB,  USB.  AM  and  FM. 

TheT-5990  is  solid-state  with  the  exception  of  only  throe  tubes,  has        It- in 

powei  supply  and  full  metering.  It  operates  CW  LSB.  USB  and  AM  and,  ol 

course,  is  a  perfect  match  to  the  R-599D  receiver. 

II  you  have  never  considered  the  advantages  of  operating  a  receiver/transmittei 

combination        maybe  you  should-  Because  of  the  larger  number  of  controls 

and  dual  VFOs  the  combination  offers  flexibility  impossible  to  duplicate  with  a 

transceiver. 

Compare  the  specs  of  the  R-599D  and  the  T599D  with  any  other  brand 

Remember   the  R-599D  is  all  solid  state  (and  includes  four  filters)  Your  choree 

will  obviously  be  the  Kenwood 


KENWOOD'S 


Dependable  operation,  superior 
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full  band  coverage  with  a  frequency 
range  of  170  KHz  to  30.0  MHz 
Receives  AMP  SSB  and  CW     Feature 
targe,  easy  to  read  drum  dials  with 
fast  smooth  dial  action     Band  sprea 
is  calibrated  for  the  10  foreign  broad- 
cast bands,  easily  tuned  with  the  use 
of  a  built  in  600  KHz  calibrator 
Automatic  noise  li miter     3  way 
power  supply  system  (AC /Batteries 
External  DC) . .  .  take  it  anyplace 
Automatically  switches  to  battery 
power  in  the  event  of  AC  power  far  lure 


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The  Kenwood  HS-4  headphone  set  adds 
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adjustable.  The  frequency  response  of  the 
HS-4  is  tailored  specifically  for  amateur 
communication  use.  (300  to  3000  Hz, 
8  ohms). 


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been  designed  expressly  for  amateur 
radio  operation  as  a  splendid  addition  to 
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and  LOCK  switches,  and  a  microphone 
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impedance,  (600  or  50k  ohm). 


TRIO  KENWOOD  COMMUNICATIONS    INC. 
116  EAST  ALONDRA/GARDENA  CA  90248 


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KENWOOD'S  EXCITING  NEW  2-METER  MOBILE  TRANSCEIVER  • 

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Full  coverage  144-148  MHz,  800  channels  in  5  KHz  steps  •  600  KHz 
repeater  offset  •  Continuous  tone-coded  squelch  (CTCS)  for  transmit 
and  receive  or  transmit  only  with  tone  elements  optional  *  Tone  burst 
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band  coverage  (144  to  148  MHz)  •  Automatically 
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reverse  •  Or  accomplish  the  same  by  plugging  a 
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EDITORIAL 


by  Wayne  Green  W2NSD/t 


ATLANTIC  CITY! 

The  Trenton  computerfest  last 
Spring  was  such  a  remarkable  success 
that  another  computer  convention  in 
the  same  general  area  was  organized 
T , ,  this  time  by  a  group  of  three  hams 
,  * ,  and  in  Atlantic  City  for  the  end  of 
August.  They  named  it  Persona] 
Computing  '76, 

PC- 76  was  a  success  by  any 
measure.  There  were  over  75 
exhibitors  and  over  3000  attendees  (at 
S5  to  S7.50  per  head),  Judging  from  a 
show  of  hands  at  my  talk  (the  room 
was  jammed  full  and  several  hundred 
were  turned  away  at  the  door),  and 
from  the  number  of  people  who  came 
to  the  73  Magazine /Kilobyte  booth, 
about  one  third  of  those  present  were 
hams.  Since  the  computer  hobby  is 
duck  soup  tor  hams  to  get  into,  I 
suppose  t  shouldn't  be  alJ  that 
surprised. 

This  was  the  first  public  announce- 


ment of  the  coming  of  Kilobyte 
Magazine,  and  I  was  most  gratified  by 
the  enthusiasm.  A  very  simple 
explanation  of  the  need  for  Kilobyte 
was  that  I  wanted  a  computer  hobby 
magazine  that  t  could  understand.  An 
awful  tot  of  people  agreed  with  me 
and  signed  up  for  subscriptions  to 
Kilobyte  .  .  .  about  three  times  what 
we've  ever  done  with  73  at  any  ham 
convention!  More  surprising  was  that 
75%  of  them  signed  up  for  three  year 
subscriptions  .  .  .  and  the  first  issue 
won't  be  out  until  December. 

MITS  was  there  with  their  latest 
equipment  set  up  and  running,  A  few 
of  the  firms  didn't  show  up  . . .  Irnsai 
let  their  dealers  do  the  showing  .  „> 
Sphere  had  one  dealer  there  with  a 
unit.  Quite  a  few  new  manufacturers 
of  small  computer  systems  showed  up 
and  won  converts  to  their  hardware.  It 
was  an  exciting  convention, 

I  got  into  my  usual  troubles.  A  few 


days  before  the  convention  I  got  a 
request  from  the  group  running  it  to 
tape  the  technical  sessions.  There  were 
going  to  be  as  many  as  five  going 
simultaneously  and  they  couldn't 
handle  It.  Hmm  .  .  I'd  have  to  get 
some  more  cassette  recorders  and  have 
at  least  five  people  there  to  make 
tapes  ,  .  .  plus  a  couple  more  to  sell 
subscriptions  at  the  booth.  It  would 
be  expensive,  but  it  would  be  good 
PR.  A  man  in  the  booth  would 
probably  be  able  to  sell  an  average  of 
$600  per  hour  in  subscriptions,  and 
Big  Bill  Edwards,  our  advertising 
manager,  sells  about  £20,000  per  hour 
in  advertising  during  a  show  like  that. 

The  idea  was  for  us  to  tape  the 
talks  and  then  make  copies  to  be  given 
to  computer  clubs  for  use  during 
meetings  .  .  .  and  to  salt  additional 
copies  of  the  tapes  at  $4,  which 
wouldn't  really  pay  for  the  effort,  bui 
would  help  take  some  of  the  sting  out. 

All  went  well  for  the  first  three 
hours  .  .  .  then  came  the  word  .  .  .  no 
more  taping.  1  gather  that  one  of  the 
computer  hobby  magazines  made  a 
big  complaint  about  it  and  all  of  the 
money  that  73  and  Kilobyte  would 
make  out  of  the  deal,  \  was  angry 
and  delighted.  A  lot  of  people  and 
clubs  would  miss  first  rate  talks  as  a 
result  of  the  politics,  and  that  was 
irritating,  I  was  glad  because  It  saved 
us  an  awful  lot  of  work  and  expense 
. , .  probably  for  little  return  of  any 
kind. 

It  was  a  pity,  since  73  is  so  well  set 
up  to  handle  this  type  of  thing.  The 
tough  part  is  having  enough  people  to 
make  the  tapes  . , .  and  then  editing 
them  down  a  bit  to  fit  a  one  hour 


cassette from  there  on  it  is  easy 

.  ,  .  except  for  the  safes  or 
distribution,  This  means  tetters  to 
clubs,  handling  orders,  keeping 
records.  And  the  sales  of  cassettes 
means  writing  ads,  having  them  set  in 
type  and  published  (a  page  ad  in  73  is 
not  cheap  .  .  .  over  Si 000  these  days}, 
so  anything  advertised  has  to  sell  and 
sell  well. 

Last  year  at  Dayton  I  tried  to  set  it 
up  so  that  we  could  tape  the  more 
interesting  talks,  only  to  have  an 
RTTYer  put  in  a  very  loud  protest  at 
"commercialism"  ...  he  would  tape 
for  free.  As  far  as  I  know  he  taped  one 
lousy  talk  and  very  few  people  ever 
got  a  copy  of  ft  -  while  thousands  of 
ham  clubs  were  prevented  by  him 
from  having  very  interesting  material 
for  meetings  .  .  .  and  the  Dayton 
Hamvention  missed  out  on  a  way  to 
get  fantastic  publicity  both  via  the 
audiences  of  thousands  of  clubs  and 
via  ads  for  the  tapes  in  73. 

A  lot  of  people  go  to  conventions 
in  order  to  hear  the  talks,  and  a  lot 
more  would  if  they  were  exposed  to 
more.  And  one  of  the  most  frustrating 
things  at  a  convention  is  to  have  two 
sessions  going  on  at  the  same  time, 
neither  of  which  can  you  bear  to  miss! 
t  noticed  that  the  Boston  convention 
had  their  talks  taped  by  a  commercial 
outfit  and  the  tapes  were  being  made 
available  for  considerably  more  than 
73  would  charge,  I  do  think  the  idea  is 
a  good  one,  but  the  cost  should  be 
kept  down  to  ham  levels  and  not  just 
be  a  way  for  some  commercial  outfit 
to  make  a  big  killing, 

Outside  of  the  taping  brouhaha,  the 
incredibly     miserable     hotel,     the 


Here's  the  Apple  computer  system  up  and  running  a  game  of  Life.  Note  the 
tiny  cassette  I/O  board  at  the  right?  This  is  a  complete  computer  and  video 
generator,  ail  on  one  board.  Any  wonder  there  was  a  lot  of  interest  in  this 
system  at  PC-76? 


The  Jolt  2K  PROM  board  is  shipped  in  a  plastic  foam  package  inside  a  carton, 
complete  with  detailed  instructions.  The  PRQMs  are  shipped  mounted  on 
conducting  foamf  to  be  plugged  in  after  receipt.  Jolt  sells  their  boards  in  kit 
form  or  assembled.  Thetr  7K  assembler  is  supplied  on  four  PRQMs  .  .  .  not  a 
bad  deaf  for  under  $JQG  including  PRQMs. 


70 


Jimmy  Chiang  checks  out  Sphere  boards  after  final  assembly  and  debugs  them. 


sauna- 1  ike  atmosphere  much  of  the 
time  in  the  convention  hall  ...  it  was 
a  resounding  success.  Atlantic  City  is 
difficult  to  get  to  .  .  .  too  far  from  any 
large  airport  for  many  exhibitors  (a 
great  portion  came  in  from 
California),  The  boardwalk  and 
amusements  were  tacky,  but  if  you 
have  a  chance  to  get  into  a  penny 
arcade  (they  are  25d  now)  don't  miss 
the  computer  games  they  have  for 
you.  You'll  find  yourself  jumping 
around  and  screaming  with  delight  at 
the  tank  game  or  the  dogfight  flying 
games.  These  are  expensive,  but  worth 
it  We  found  one  arcade  where  eight 
people  could  play  at  onceH  each 
driving  his  own  tank  and  shooting  at 
the  other  seven.  The  games  are  quite 
sophisticated,  so  be  sure  to  give  em  a 
try  the  next  time  you  see  one. 

These  arcade  games  are  just  a  hint 
of  some  of  the  goodies  coming  for 
home  computer  use.  The  new  six 
game  television  toys  are  now  on  the 
market  and  are  fun  (under  SGO  some 
places  .  .  .  Unisonic}.  but  they  are 
simple  compared  to  some  of  the 
microprocessor  games  that  are 
coming,  The  arcade  games  use  an  FS 
FairchSJd  microprocessor  and  are  run 
by  software.  It  won't  be  long  before 
those  programs  are  available  for 
computer  hobbyists. 

I/O  A  WINNER 

A  large  percentage  of  the  hams  at 
trie  Atlantic  City  computer  conven- 
tion and  sauna  said  that  the  I/O 
articles  in  73  had  been  their  introduc- 
tion to  hobby  computing.  The  fact  is 
that  aside  from  Interesting  the  people 
already  in  the  computer  industry  in 
going  into  their  work  as  a  hobby. 
there  has  been  tittle  effort  so  far  to 
attract  outsiders  to  hobby  computing, 

One  big  problem  is  that,  other  than 
the  material  in  73,  there  has  been 
practically  nothing  published  which  is 
understandable  to  the  beginner,  The 
series  of  articles  which  ran  In  73 
introducing  newcomers  to  the  world 
of  computing  have  been  gathered  Into 


a  book  called  Hobby  Computers  Are 
Here.  This  is  being  sold  through  radio 
stores  for  S4.95  by  73  Magazine. 

The  computer  hobby  magazines 
have  gotten  into  the  hands  of  people 
who  are  more  interested  in  esoteric 
articles  for  professionals  than  in  help- 
ing novices  come  up  to  speed  in  this 
difficult  field.  Kilobyte  Magazine 
promises  to  help  solve  this  impass  by 
publishing  a  high  percentage  of 
articles  written  for  the  beginner  . .  . 
and  further,  there  will  be  a  glossary  of 
the  technical  terms  and  buzzwords  in 
each  issue, 

73  has  so  far  withstood  the  tempta- 
tion to  try  and  promote  the  I/O 
sect  ton  of  the  magazine  to  computer 
hobbyists.  While  this  would  make  for 
better  results  for  I/O  advertisers,  it 
might  be  somewhat  detrimental  to 
ham  advertisers,  since  only  about  26% 
of  the  computer  hobbyists  are  into 
hamming  so  far.  This  may  change.  The 
current  issue  of  Computer  Notes ,  the 
official  publication  of  MITS,  has  a 
lengthy  editorial  on  the  benefits  of 
amateur  radio  for  computerists  .  . . 
and  president  Ed  Roberts  is  hard  at 
work  aiming  at  a  General  ticket  as 


This  is  Steve  Jobs,  the  president  of  Apple  and  the  chap  who  designed  the 
system.  How  many  twenty  year  old  computer  designers  do  you  know  with 
their  own  manufacturing  firms? 


soon    as    possible.    Perhaps   the   two 
fields  will  grow  even  closer  together, 

VISITING 

During  August  I  made  a  quick  trip 
around  the  country  to  see  how  the 
hobby  computer  industry  was  doing 
. , ,  and  to  update  myself  on  the 
similar  trip  I  made  the  year  before. 

My  first  visit  was  to  Ray  Holt  and 
the  Jolt  computer.  This  is  an 
interesting  development,  and  far  too 
little  has  been  written  about  it.  Ray 
has  agreed  to  explain  some  of  the 
interesting  ideas  he  has  built  into  the 
system  in  an  article  for  Kilobyte.  I 
suspect  that  Ray  would  be  a  whole  lot 
busier  if  more  people  understood 
what  he  has  done  with  the  Jolt. 

Next  was  a  visit  to  ImsaL  They'd 
just  moved  to  a  new  and  larger  plant, 
but  refused  to  let  me  see  anything  or 
take  any  pictures  of  the  operation. 
That's  the  first  time  I've  ever  run  tino 
anything  like  that  and  I  didn't  know 
what    to    make   of    it. 

Apple  Computer  was  a  surprise  ,  , . 
a  corner  of  a  garage  in  a  home,  Steve 


Jobs,  twenty  years  old.  designed  and 
built  the  system  with  programming 
help  from  friend  Steve  Wosniak.  He 
has  some  remarkably  good  ideas  in  the 
system  and  I  was  very  impressed,  I 
strongly  suggested  that  they  pack  the 
system  off  to  Atlantic  City  for  the 
PC-76  show  coming  up.  They  did,  and 
Steve  came  back  with  a  bunch  of 
orders  and  dealers  (about  40  orders.  I 
believe)  ...  not  bad!  He's  going  to 
have  his  hands  full  as  his  company 
grows  rapidly.  Steve  has  promised  an 
article  on  his  design  for  Kilobyte, 

Todd  Anderson  of  Byte  Shop  -2 
has  promised  an  article  on  the  Z  80 
computer  system  the  Byte  Shops  will 
be  manufacturing  soon,  Todd  is  giving 
classes  on  the  fundamentals  of 
computers,  and  has  promised  articles 
for  Kilobyte  on  the  same  subject. 

One  of  the  really  exciting  visits  was 
with  Bill  Godbout  in  Oakland.  He  sells 
an  incredible  amount  of  IGs  and  asso- 
ciated parts,  His  warehouses  are  piled 
up  to  here  with  stuff  , .  .  and  any  ham 

Continued  on  page  t73 


Video  generator  board  kits  at  Sphere  awaiting  delivery  of  a  few  more  needed  parts  such  as  7493  fCs.  Parts  are  mounted  on 
foam  plastic  with  both  parts  numbers  and  valuss  printed  on  a  sheet  on  top  of  the  foam.  This  makes  it  simple  to  find  and 
use  parts  as  the  kit  is  assembled. 


71 


Imagine  a  microcomputer  with  alt  the  design  savvy,  ruggedness. 
and  sophistication  of  the  best  minicomputers 

Imagine  a  microcomputer  supported  by  dozens  of  interface,  memory, 
and  processor  option  boards.  One  that  cart  be  interlaced  to  an  indefinite 
number  of  peripheral  devices  including  dual  floppy  discs.  CRT's,  line 
printers,  cassette  recorders,  video  displays,  paper  tape  readers,  tele 
printers,  plotters,  and  custom  devices. 

Imagine  a  microcomputer  supported  by  extensive  software  including 
Extended  BASiC,  Disk  BASIC,  DOS  and  a  complete  library  ol  business, 
developmental,  and  industrial  programs 

Imagine  a  microcomputer  that  will  do  everything  a  mini  will  do,  only 
at  a  fraction  o!  the  cost 

You  are  imagining  the  Altair1*  8800b.  The  Altair  8800b  is  here 
today,  and  it  may  very  welt  be  the  mainframe  of  the  70  s 

The  Altair  880Ob  is  a  second  generation  design  of  the  most  popular 
microcomputer  in  the  field,  the  Altair  8800    Built  around  the  8800A 
microprocessor,  the  AM  air  8800b  is  an  open  ended  machine  that  is 
eornpalible  with  all  Altair  8800  hardware  and  software.  It  can  be  con 
figured  to  match  most  any  system  need. 

Introductory  prices  for  the  Altair  8800b  are  S840  for  a  kit  with 
complete  assembly  instructions,  and  $1100  for  an  assembled  unit  Com- 
plete documentation,  membership  into  the  Allair  Users  Club,  subscrip 
tion  to  "Computer  Notes'*  access  to  the  All  air  Software  Library  and  a 
copy  of  Charles  J.  Sippl's  Microcomputer  Dictionary  are  included 
BankAmencard  or  Master  Charge  accepted  for  mail  order  sales  Include 
$8  for  postage  and  handling. 

Shouldn't  you  know  more  about  the  Altair  8800b?  Send  for  our  free 
Altair  Informal  ion  Package  or  contact  one  of  our  many  retail  Altair 
Compuler  Centers. 

MITS,  Inc  1976/2450  Alamo  S.E. /Albuquerque,  New  Mexico  87106 


tm 


Redesigned  front  panel,  Totally  synchro- 
nous logic  design.  Same  switch  and  LED 
arrangement    as    original    Altair    8800. 
New  back-lit  Duralith  (laminated  plastic 
and  mylar,  bonded  to  aluminum)  dress 
panel    with    multi-color    graphics.    New 
longer,   flat   toggle  switches.   Five   new 
functions  stored  on  front  pancf   PROM 
including:  D1SPLAV  ACCUMULATOR  (dis* 
plays  contents  of   accumulator),    LOAD 
ACCUMULATOR  (loads  contents  of  the 
8  data  switches  (A7-AO)  into  accumulator! 
OUTPUT  ACCUMULATOR  (Outputs  con- 
tents of  accumulator   to   I/O  device 
addressed    by   the    upper    8    address 
switches],   INPUT   ACCUMULATOR   (in- 
puts to  the  accumulator  from  the   I/O 
device),    and    SLOW    (causes    program 
execution  at  a  rate  of  about  S  cycles  per 
second  — for  program  debugging). 


Fulf  18  slot  motherboard, 

Rugged,    commercial    grade    Optima 
cabinet* 

New  front  panel  interface  board  buffers 
all  lines  to  and  from  8800b  bus. 

Two,  34  conductor  ribbon  cable  assem- 
blies. Connects  front  pane*  board  to  front 
panel  interface  board.  Eliminates  need 
for  complicated  front  panel /bus  wiring. 


• 


New,  heavy  duty  power  supply  I  8  volts 
at  18  amps,  +  18  volts  at  2  amps,  18  volts 
at  1  amps.  110  volt  or  220  volt  operation 
(50/60  Hz).  Primary  tapped  for  either 
high  or  low  line  operation 

New  CPU  board  with  8080 A  micro 
processor  and  Intei  8224  clock  generator 
and  8216  bus  drivers.  Clock  pulse  widths 
and  phasing  as  well  as  frequency  are 
crystal  controlled.  Compatible  with  all 
current  Altair  8800  software  and 
hardware. 


Price,  specifications  suDi  est  to  change    Pi  ease  allow  up  to  60  day  5  to*  deitveiy 


REPORT 


by  John  Craig 


PERSONAL 

COMPUTING 

'76 

We  just  returned  from  Atlantic  City 
NJ  after  a  tremendous  weekend  at  one 
of  the  best  convent  ions  the  hobby 
community  has  had  yeL  The  conven- 
tion was  sponsored  by  the  Southern 
Counties  Amateur  Radio  Association 
of  New  Jersey,  Inc,  The  whole  thing 
was  practically  a  three-man  show, 
with  the  bulk  of  the  work  and 
coordination  being  done  by  John 
Diiks  K2TQN  Dave  Jones  WA2AML, 
and  Jim  Main  YVB2UGN  With  over 
3,000  in  attendance,  you  can  bet 
these  three  gentlemen  {and  their 
associates)  had  their  hands  full  1 

About  the  only  thing  I  found 
lacking  were  booths  set  up  for  indi- 
viduals to  display  their  systems.  Since 
ham  radio  is  one,  if  not  the.  area 
which  has  found  some  truly  inter- 
esting applications  for  microprocessor 
systems,  it  would  seem  there  could 
have  been  some  fascinating  exhibits 
set  up  by  local  hams.  Needless  to  say, 
an  adjustment  to  the  Si 00  fee  for  a 
booth  would  be  necessary  before 
many  folks  would  even  consider 
bringing  their  systems  to  Atlantic  City 
for  just  show. 


KILOBYTE 

Personal  Computing  76  provided 
the  "launching  platform"  for  our  new 
magazine.  Kilobyte.  (As  you  probably 
know,  the  publisher  of  Kilobyte  m 
also  the  man  who  started  8yte 
magazine  .  .  .  and  it  turns  oat  he  has  a 
neat  sense  of  humor  when  it  comes  to 
such  things  as  magazine  namesf)  The 
Kilobyte  booth  was  one  of  the  most 
popular  at  the  convention  and  I'm  not 
sure  if  it  was  because  we  had  some  of 
the  most  interesting  merchandise  on 
display  or  because  we  had  some  of  the 
most  interesting  (and  cute)  young 
ladies  behind  the  counter  I  Besides  the 
Kilobyte  subscriptions  (which  were 
being  bought  left  and  right K  we  had 
recent  back  Issues  of  73 \  computer 
and  ham  books,  code  tapes,  and  much 
more.  We  also  had  a  Kilobyte  drawing 
for  a  Windjammer  cruise  for  two 
through  the  Caribbean.  Byron  Young 
of  Pasadena  TX  was  the  lucky  winner 
Of  that  little  jaunt. 

One  of  the  questions  we  heard  most 
concerning  Kilobyte  was,  "What  is  it 
going  to  provide  that  the  other 
magazines  don't?"  It's  for  sure  we'd 
be  spinning  our  wheels  if  we  didn't 
have  plans  for  Kilobyte  to  be  unique 
and  special.  One  of  the  things  we  will 
definitely  be  providing  through  the 


pages  of  Kilobyte  will  be  ancles 
dealing  with  both  hardware  and  soft- 
ware for  the  beginner.  Now,  stop  and 
think  about  that  for  a  moment:  There 
are  hardware  types  and  software  types 
in  this  computer  "business"  and  it's 
very  seldom  that  a  person  is  well- 
versed  in  both  areas.  If  you're  one  of 
the  hardware  group  who  enjoys 
designing  and  building  state  of  the  art 
circuits,  it's  very  likely  you  have  a  lot 
to  learn  about  the  programming  end 
of  things.  And,  if  you're  a  top-notch 
programmer,  you  probably  have  a  lot 
of  questions  about  the  hardware  end, 
(Heck,  you  might  even  have  those 
questions  if  you're  a  mediocre  pro- 
grammer I J  Then(  of  course,  there's  the 
poor  guy  just  getting  started  in  this 
whole  mess  who  doesn't  have  much  to 
carry  him  through  except  deter- 
mination and  a  keen  desire  to  learn, 

These  articles  are  going  to  be  just 
what  you've  been  looking  for.  We're 
not  going  in  for  straight  tutorial 
material  .  .  .  instead,  you'll  be  reading 
articles  which  have  good  practical 
examples  we  can  all  relate  to,  and 
good,  useful,  practical  applications. 

Kilobyte  will  also  be  covering  appli- 
cations in  both  the  home  and  small 
businesses  (and  you  can  be  sure  that  a 
lot  of  these  "hobby  '  efforts  are  going 
to  be  shifting  over  in  the  direction  of 
developing  small  business  systems). 
You  can  be  Just  as  sure  of  keeping 
Up-to-date  on  developments  in  this 
area  through  Kilobyte. 

We're  looking  for  programs  for  the 
Kilobyte  Software  Ubrtry,  This  rs 
going  to  be  the  place  for  getting 
applications  programs,  games,  educa 
tional  programs,  diagnostics  and  other 
software  for  making  your  home 
system  something  more  than  just  an 
ol'  light  blinker.  It's  going  to  be  a 
fantastic  deal  for  you,  the  program- 
mer, because  you  will  have  a  means  of 
marketing  your  programs  and  being 
paid  a  royalty  on  each  copy  sold. 
(These  programs  are  going  to  be  distri- 
buted throughout  the  country  at 
computer  stores,  as  well  as  being 
advertised  and  sold  through  73  and 
Kilobyte.)  It's  going  to  be  great  for 
everyone  because  we'll  finally  have 
somewhere  to  go  for  the  software 
we've  all  been  craving! 

PETERBOROUGH, 
NEW  HAMPSHIRE 

After  the  Atlantic  City  convention, 
I  drove  up  to  New  Hampshire  with 
?J\  computer  engineer,  Jim  Muehlen 
This  was  my  first  trip  to  the  northeast 
and  I'm  still  in  a  state  of  shock  over 


the  fact  the  toll  road  charges  we  paid 
during  that  trip  were  almost  double 
the  cost  of  the  gasoline  I 

Looking  at  the  brighter  side  of 
things  ...  let  me  tell  you  about 
Peterborough!  It's  a  truly  beautiful 
and  quaint  little  New  England  town 
with  some  of  the  friendliest  people 
you'll  find  anywhere.  And,  if  you're 
ever  passing  through  around  eat  in' 
time,  be  sure  and  stop  at  the  Folkway 
Restaurant  for  some  fine  dishes  (and 
some  unusual  company  ...  such  as 
Carl  Helmers,  the  editor  of  BYTE). 

The    group    at    73   is   a   sight   to 

behold,  also.  Some  wonderful  and 
dedicated  people  put  together  this 
magazine  you  all  enjoy  so  much.  The 
house  In  which  alt  this  takes  place  is  a 
200  year  old  mansion  which  has  mom 
rooms  than  any  one  man  could  count 
in  a  lifetime,  it's  a  beautiful  piace 
with  a  lot  of  atmosphere,  and  if  you 
ever  read  one  of  Wayne's  "ads"  for 
help  up  in  Peterborough,  you  could 
do  worse  than  to  answer  it, 

STEVE  CIARCIA'S 
VIDEO  GAME  ARTICLE 

The  October  73  had  an  article  by 
Steve  Ciarcia  entitled,  ''Hey,  Look 
What  My  Daddy  Built!"  It  described 


the  construction  of  a  video  game  using 
the  6  game  AY5-8B00  chip  manu- 
factured by  Generai  Instruments.  It 
teems  there  aren't  too  many  places 
where  one  can  get  hold  of  this  chip. 
He  (Steve)  has  been  detuged  with 
requests  on  where  to  get  it,  and  the 
phone  at  73  hasn't  stopped,  either, 
We've  been  tokJ  that  the  chip  is 
available  for  S3 9. 95  from  Advanced 
Micro- Computer  Products,  P.O.  Box 
17329,  Irvine  CA  92713.  The  latest 
Heathkit  video  game  (released  in 
October)  uses  the  same  chip  and  sells 
for  $49.95. 


NEW  PRODUCT 
REVIEW 

Oliver  OP-80A 
Tape  Reader 
The  OP-80A  "high  speed"  paper 
tape  reader  is  probably  one  of  the 
least  expensive  and  easiest  devices 
you're  going  to  run  across  for  getting 
programs  into  your  computer.  Unlike 
most  other  paper  tape  readers,  you 
won't  have  to  worry  about  mechanical 
repairs  and  alignments  ,  . ,  since  the 
movement  of  the  tape  is  accomplished 
by  pulling  it  through  the  reader.  Then, 
on  the  other  hand,  you're  not  going  to 

Continued  on  page  121 


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IMSAI  8080 


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IMSAI  8080  Kit,  $540.00 
IMSAI  8080  Assembled,  $829.00 
IMSAI  4K  Low  Power  Memory  Board, 


OTHER 

PRODUCTS  OF 
EXCEPTIONAL 
MERIT 

The  I/O  board  and  printer  were  developed 
for  our  In-House  commercial  products.  They 
are  extremely  well- built,  of  high  Quality  and 
are  excellent  for  the  discriminating  hobbyist 


thittkT  "WW  tn  5ot**h  If,     a,n  Ken,, 

,         ,   m  ^h  „f°  '«  give  »le  \  °f  Us  Ang*'*"'  ofa  sm  . 

,n    Ser»  '*-' benefit    Mv  *inu,'  C"I'foL      a/I 

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lod°r.    dTty-  ^^'^<ni^^^l^^c4 

\         mas  H*  Lf'fo""*  uL  off*'**  1  A°v^ber'7^Pr^es- 

atm°*t  on  ,    lent>  ^e  eTUv  ^'mlai,    °8°  »*<**»  *"*  *» 

of,?*  Wto!'*»C?  FOCAL     '  Qnd  "'eat?* 

Abased ku  °U      <*nno?  l*S4L  /,£. *j**J 

better 


MMI  Model 


PENER 


6  FORTS  of   parallel   which  can  be  anv  combination  of  in  and  out 

tsof  tware  control) 

5  PORTS  In  and  1  out,  2  in  and  4  out, ate, 

2  PORTS  set ial  interface,  or  20  mil  current  loop  and  one  R5  232  or 

both  PORTS  either  typ*. 

Board  select  1 1 0  to  9600  baud. 

Kit  oriee ..,....*... .  $219  95/each 

DECWRLTER    LA   36    1 1    30   CPS   printer  brand  new   En   box  from 
factory,  air  shipped  to  your  door    ..♦♦,♦., $1  776*00 


MMI  Model  40P 

5k?  dot  matrix  impact  type 

40    column     alphanumeric    printer     w/PS,     case     and     interface    tp 

IMSAI/MiTS 

Double  size  print  under  software  control  —  1 ,25  lines  per  second. 

Assembled  price £599-00/each 

Introductory  price .  ,  »  h .  $51  9.00/each 


TERMS:  Cast),  check,  or  money  order.  We  cannot  accept  any  charge  cards;  however  your  bank  will  advance  you  the  cash  — 

your  payments  are  the  same.  Make  out  your  check  and  mail  to: 

UlkCRDPRaCESSDR  ITlflRhETinG,  inC 

1724  SANTA  FE  AVENUE,  LONG  BEACH,  CA  90813 

Inquire  as  to  quantity  club  discounts  -  IMSAI  products  only. 


COMPUTEP 


COMPUTER 


•  COMPLETE  WITH  2K  OF  MEMORY 

•  SERIAL  INTERFACE 

•  STANDARD  ROM  MONITOR  (Motorola  MC  B830L7) 

•  4K  AND  8K  BASIC  AVAILABLE 


Always  the  best  value  in  hardware  and  now  an  outstanding 
selection  of  software  too.  What  more  could  you  want  in  a 
computer  system?  For  less  than  four  hundred  dollars  you 
get  everything  you  need— ready  to  connect  to  a  terminal 
and  go  to  work.  No  surprises  no  funny  business,  just  good 
reliable  hardware  in  a  very  practical  system  that  may  be  ex- 
panded to  meet  almost  any  later  need, 

Memory  and  interfaces  are  not  extra  cost  items  in  our 
system,  A  standard  Motorola  MIKBUG®  ROM  monitor 
makes  the  system  completely  compatible  with   Motorofa 

®  Motorola 


software  and  eliminates  any  need  for  console  switches  and 
light.  Data  may  be  entered  from  the  terminal  in  convenient 
hexidecimal  form,  The  power  supply  is  adequate  to  operate 
a  fully  expanded  system  with  up  to  24 K  of  memory  and  up 
to  eight  (8)  interfaces— simultaneously. 

See  the  6800  and  our  peripheral  equipment  at  your  nearest 
dealer,  or  write  for  a  complete  description. 

MP-68  COMPUTER  KIT-with  serial  interface, 

2k  of  memory  and  ROM  monitor  $395.00  ppd 


Southwest  Technical  Products  Corporation,  219  W.  Rhapsody,  San  Antonio,  Texas  73216 


See 


computer  equipment  at  your  local   dealer 


CALIFORNIA 
The  Electric  Brain  Computer  Store 
700  Village  Parkway,  Suite  L 
Dublin,  Ca.  94566 
(415}  828  7480 

Computerware 
830  First  St. 
Encinitas,  Ca.  92024 
(714)  436-3512 

Cvberciux 

Microcomputer  Applications 
1210  Santa  Fe  Dr. 
Encinitas,  Ca.  92024 
(714)  279-4189 

A-VID  Electronics  Co. 
1655  East  28th  St. 
Long  Beach,  Ca.  90S06 
(213)426-5526 

The  Byte  Shop  Computer  Store  #  1 
1063  El  Camino  Real 
Mountain  View,  Ca.  94040 
(415)969-5464 

The  Computer  Center 
8205  Ronson  Rd, 
San  Diego,  Ca.  921 1 1 
(714)  292-5302 

Computer  Store  of  San  Francisco 
1093  Mission  St, 
San  Francisco,  Ca.  94103 
(415)  431-0640 

The  Byte  Shop  Computer  Store  #  2 
3400  El  Camfno  Real  ■ 
Santa  Clara,  Ca.  95051 
(408)  249-4221 

The  Computer  Store 
820  Broadway 
Santa  Monica,  Ca.  90401 
(213)  451-0713 

FLORIDA 

Electronics  for  Yachting,  Inc. 
2001  S.W.20th  St. 
Ft.  Lauderdaler  FL  33315 
(305)  525-3479 

Computer  Assoc,  Inc. 

6900  f\L  Kendall  Dr,,  Suite  A103 

Miami,  Fl.  33156 

Marsh  Data  Systems 

5405-B  Southern  Comfort  Blvd. 

Tampa,  FL  33614 

(813)  886-9890 

Microcomputer  Systems,  Inc. 
144  S,  Dale  Mabry  Ave, 
Tampa,  FL  33609 
(813)  879-4301 

GEORGIA 
Atlanta  Computer  Mart 
509 1-B  Buford  Highway 
Atlanta,  Ga,  30340 
(404)  455-0647 


ILLINOIS 

American  Microprocessors 
Equipment  &  Supply  Corp. 
241  Indian  Creek  Rd. 
Prairie  View,  11,60069 
(312)  634-0076 

INDIANA 
The  Data  Domain 
111  S.  College  Ave. 
Bloornington,  In.  47401 
(812)  334-3607 

KANSAS 

Midwest  Scientific  Instruments,  Inc. 
220  W.  Cedar 
Olathe,  Ks.  66061 
(913)  764-3273 

KENTUCKY 
Cybertronics 
312  Production  Ct. 
Louisville,  Ky.  40299 
(502)  499-1551 

LOUISIANA 
Baxter's  T.V. 
7964  Jefferson  Hwy, 
Baton  Rouge,  La,  70809 
(504)  924-5303 

MARYLAND 
The  Computer  Workshop,  Inc. 
5709  Fredrick  Ave. 
Rockville,  McL  20852 
(302)  468-0455 

MASSACHUSETTS 
Computer  Warehouse  Store 
584  Commonwealth  Ave, 
Boston,  Ma,  02215 
(617)  261-2701 

Control  Concepts 

P.O.  Box  272 

Needham  Heights,  Ma,  02194 

NEVADA 
Johnson  T.V.f  Inc. 
2607  E,  Charleston 
Las  Vegas,  Nvr  89104 
(702)  382-5553 

NEW  HAMPSHIRE 
Aircom,  Inc, 
Route  16-B 
Union,  N.H. 03887 
(603)  473-2323 

NEW  JERSEY 

William  Electronics  Supply 
1-863  Woodbridge  Ave. 
Edison,  N.J.  08817 
(201)  985-3700 

Midwest  Enterprises,  I'ric, 

815  Standish  Ave. 
Westfield,  N, J.  07090 
(201)  233-7090 


NEW  YORK 
Synchro-Sound  Enterprises 
193-25  Jamica 
Hollis,  N,Vfi  11423 

Audio  Design  Electronics 
487  Broadway,  Room  512 
New  Yorkr  N.Y.  10013 
(212)  226-2038 

Computer  Mart  of  New  York,  Inc. 

314  Fifth  Ave, 

New  York,  N.Y,  10001 

(212)  279-1048 

Waco  Trading  Co.,  Inc. 
239  Park  Avenue  South 
New  York,  N.Y.  10003 
(212)  674-0470 

OHIO 

ELS  Systems 
2209  N.  Taylor  Rd. 
Cleveland  Heights,  Oh.  44112 
(216)  249  7820 

PENNSYLVANIA 
Martin  J.  O'Boyle  &  Assoc. 
P.O.  Box  9094 
Pittsburgh,  Pa.  15224 
(412)  361-1602 

UTAH 
The  Computer  Room 
1455  South  1100  East 
Salt  LakeCityr  Ut.  84105 
(802)  466-7911 

TEXAS 

Printing  Si  Office  Supply  Co. 

of  Texas,  Inc, 

130  One  Shell  Plaza 

Houston,  Tx.  77002 
(713)  228-8966 

The  Micro  Store 
634  S.  Central  Expressway 
Richardson,  Tx.  75080 
(214)  231-4088 

WASHINGTON 
Retail  Computer  Store 
410  IM.E,  72nd  St. 
Seattle,  Wa.  98115 
(206)  524-4101 

WISCONSIN 
The  Milwaukee  Computer  Store 
6916  W.  North  Ave. 
Milwaukee,  Wi.  53213 
(414)  259-9140 

FOREIGN 
Computer  Resources 
Chaussee  cle  Charieroi,  80 
1060  Brussels,  Belgium 

SDS  Technical  Devices,  Ltd. 
1138  Main  St. 

Winnipeg,  Man.  R2W  3F3  Canada 
(204)  589-4803 

The  Entryphone  Co.,  Ltd. 

172  Ifield  Rd, 

London  SW  10  9AG,  England 

01-373-8571 


^m 


Louis  I  Mutton  K7YZZ 
1 223S  S,E.  62nd  St. 
Bellevue   WA  98006 


Ham's  Computer 


-  -  CW/RTTY  the  easy  way 


For  several  years  I  have 
experimented  with, 
built,  and  operated  different 
items  of  SSTV  equipment. 
From  that  experience  I  tried 
my  hand  at  building  an  all 
solid  state  RTTY  TVT  which 
was  recently  described  in  73 
Magazine. l  In  monitoring 
ham  RTTY  transmissions  on 
the  West  Coast,  it  was  noted 
that  the  subject  of  microcom- 
puters and    their  application 


to  ham  radio  was  being 
discussed  in  increasing  fre- 
quency. My  curiosity  was 
aroused  about  this  new 
development  in  ham  radio. 

I  was  fortunate  in  being 
able  to  visit  Dr.  Robert 
Suding  W0LMD  several  times 
during  business  trips,  and 
observed  the  development  of 
the  microcomputer  that  is 
now  marketed  by  The  Digital 
Group  of  Denver,  Colorado.2 


For  my  ,(hands-onM  experi- 
ments in   microcomputers,   I 

purchased  their  type 
8080-4BD  kit,  1  feel  that  I 
was  probably  like  other  hams 
and  did  not  have  the  slightest 
notion  of  how  this  thing 
worked,  but  figured  to  just 
jump  in  and  have  a  go  at  it,  I 
must  say  it  has  been  a  very 
interesting  project.  I  am 
slowly  learning  to  live  with 
the  new  system  and  to  use  it 


ffS«*o! 


in     some    practical    applica- 
tions. 

System  Description 

The  8080-4 BD  system  as 
shown  in  the  block  diagram 
consists  of  several  PC  boards 
and  the  components  that 
must  be  mounted  on  the 
boards.  This  includes  the 
standard  mother  board,  a 
CPU  board  with  2K  of 
memory,  an  8K  memory 
board  using  2102  ICsl  a  video 
display  and  cassette  interface 
board,  and  a  4-port  parallel 
I/O  board. J  The  mother 
board  will  accommodate  two 
more  8K  memory  boards  and 
three  more  4-port  I/O  boards. 
Low  profile  sockets  are  used 
for  mounting  all  ICs.  An  un- 
mounted surplus  keyboard 
with  ASCII  encoded  output 
was  also  purchased  from  The 
Digital  Group. 

A  12  inch  transistorized 
black  ^nd  white  TV  set  was 
used  for  the  video  display. 
The  display  consists  of  16 
lines  of  32  characters  per  line. 
For  the  cassette  "Read11  and 
"Write"  modes,  I  use  a  Super* 
scope  Model  C-104  as  recom- 
mended in  the  technical 
literature  that  accompanies 
the  kit.  Power  supplies  in 
both  kit  and  assembled  form 
are  available  from  The  Digital 
Group,  but  I  chose  to  build 
my  own.  The  cabinet  for  the 
mother  board,  PC  boards  and 
power  supply  was  salvaged 
from  an  old  obsolete  tube 
transmitter.  I  also  fabricated 
a  cabinet  for  the  keyboard 
assembly.  The  TV  set  was 
modified  to  accept  video 
input  from  the  computer. 

Included  in  the  parts  from 
The  Digital  Group  is  a  pre- 
recorded tape  cassette  that  is 
used  to  initialize  the  system 
and  to  test  out  the  memory 
card.  It  also  has  a  game  pro- 
gram, a  program  to  make  the 
unit  act  as  a  digital  counter,  a 
bicentennial  demonstration 
program,  and  a  ham  CW  and 
RTTY  program.  The  bicen- 
tennial program  on  the  tape 
prints  an  American  flag  on 
the  TV  screen  to  the  accom- 
paniment of  The  Star- 
Spangled     Banner,     As     Dr. 


M 


78 


Sudmg  says,   "So  what  else 
would  you  expect  in  1976?" 

Assembly  of  the  System 

It  is  stressed  in  the  data 
furnished  with  the  kit  that 
the  builder  should  have  some 
experience  in  building  elec- 
tronic equipment  other  than 
assembling  detailed  kits  from 
Benton  Harbor.  The  data 
does  not  give  that  kind  of 
step-by-step  instructions.  The 
quality  of  the  PC  boards  is 
first  class,  with  gold-plated 
connector  contacts  and 
double-sided  boards  with 
through-plated  holes.  General 
instructions  on  how  to 
assemble  each  PC  board  are 
given,  with  a  description  of 
how  the  circuit  works.  A 
schematic  diagram  is 
furnished  for  each  board, 
along  with  a  general  parts 
layout  for  that  particular 
board*  Testing  and  trouble- 
shooting information  is  also 
furnished  in  the  data  package. 

In  assembling  my  system,  I 
discovered  one  board  that 
was  missing  all  the  bypass 
capacitors.  They  were  imme- 
diately replaced  when  The 
Digital  Group  was  advised  of 
the  shortage.  Another  board 
had  one  low  cost  IC  missing 
which  I  replaced  from  my 
junk  box.  Another  board  had 
one  extra  IC  in  the  kit.  After 
the  unit  was  finally  assembled 
and  ready  to  test,  I  ran  into 
several  bugs*  The  characters 
on  the  video  monitor  were 
not  complete,  and  it  looked 
more  like  a  foreign  language 
than  English.  I  found,  after 
consultation  with  Dr.  Suding, 
that  I  had  a  bit  missing  on  the 
data  lines  going  into  the  video 
board.  This  was  determined 
to  be  caused  by  a  lack  of 
through-plating  in  one  of  the 


holes   in   the   mother  board. 

The  next  bug  was  that  a 
portion  of  the  dot  structure 
was  missing  in  the  characters 
being  displayed.  This  was 
found  to  be  caused  by  a 
defective  Motorola  (MCM 
6571  L)  character  generator 
chip  which  was  promptly 
replaced  (once  again)  by  The 
Digital  Group*  The  last  bug 
was  that  the  encoder  chip  (Tl 
TMS^SQGO)  in  the  keyboard 
had  to  be  replaced  (as  one 
row  of  keys  was  dead).  With 
those  bugs  out  of  the  way  the 
system  worked  as  designed. 
The  power  supply  shown 
in  the  diagram  was  home- 
made, and  provides  all  the 
voltages  required  at  the 
specified  current  loads*  I  had 
to  salvage  an  old  63  volt  20 
Amp  transformer  and  rewind 
it  with  a  new  secondary  for 
the  high  current  5  volt  load. 
A  second  winding  was  also 
added  for  the  +12  volt  line. 
The     crowbar     circuit     was 


I2  INCH 

TV 
MONITOR 

STANDARD  MOTHER  BOAR0 
EXPANSE  FOB  — 
3EAHK  MEMORY  BOARDS 
4EA  4  PORT   I/O  BOARDS 

* 

PQ*ER   SUPPLY 
-5Y 

*\Zv 

-IZV 

ASCII 
ENCODED 
KEYBOARD 

I 

^T 

'        * 

^^— ^-l. 

_T~^      U 

r1        u 

CASSETTE 

TAPE 
RECOrtOEfl 

A  PORT 

TV-CA5SE1  TL 
INTERFACE 

8090  CPU 

AND 
2K  MEMORY 
#    BOARD 

9  K  MEMORY 

EC 
* 

ARD 

BC 

* 

JARD 

MM 

* 

kRD 

Fig.    7.  Block  diagram  of  microcomputer  system  at  K7YZZ. 
*/ terns  basic  to  the  8Q8Q-4BD  kit. 


added   to    protect   all   those 

expensive  ICs  on  the  memory 
and  CPU  card.  Discussions 
with  Dr.  Suding  indicated 
that  anything  less  than 
50,000  uF  in  the  5  volt 
power  supply  filter  might 
lead  to  unwanted  noise  prob- 
lems. I  located  just  what  was 
needed  in  a  local  surplus  store 
and  ended  up  with  a  55,000 
uF  unit. 

The  cabinet  for  the 
computer  is  I8/2  inches  wide 
by  9  inches  high  by  12  inches 
deep,  I  cut  two  large  square 
holes  in  the  top  and  riveted  in 
a  perforated  grille  for  better 
circulation  of  cooling  air.  A  4 
inch  fan  is  mounted  on  the 
compartment  divider  bulk* 
head  between  the  power 
supply  compartment  and  the 
PC  board  compartment.  The 
air  is  directed  over  those 
warm  memory  chips.  I  have 
had  no  problems  with  over- 
heated ICs.  The  MPC-1000  5 
volt  10  Amp  regulator  is 
mounted  on  a  very  large  heat 
sink  on  the  back  bulkhead, 
out  in  the  open  air.  This  way 
it  does  not  dump  its  heat  into 
the  unit. 

The  12  inch  TV  set  was 
modified  as  per  a  TV  type- 
writer article  in  BYTE  Maga- 
zine* The  level  of  the 
video  signal  from  the  com- 
puter was  more  than  the  TV 
set  could  handle,  and  re* 
quired  additional  line  loading 


before  the  set  began  to 
display  the  signal  on  the 
screen  at  an  acceptable 
brightness  and  contrast  level. 
The  builder  should  not  use  a 
TV  set  that  does  not  have  a 
power  transformer  providing 
power  line  isolation.  Be  sure 
that  the  set  does  not  have  a 
"hot"  chassis  with  series 
string  heater  tubes.  That  type 
will  really  fry  the  ICs  in  a 
computer. 

I  found  that  when  playing 
the  cassette  into  the  com- 
puter I  could  not  monitor  the 
audio  signal,  so  I  modified 
the  recorder  by  adding  a  100 
Ohm  resistor  across  the 
output  jack  switch  contacts 
so  that  the  speaker  was  in  the 
circuit  even  when  an  audio 
line  plug  was  connected  to 
the  recorder  output.  It  is  con- 
venient to  monitor  the  mark 
frequency  tone  as  the  pro- 
gram  playback  begins  and 
ends. 

Initial  Test 

When  power  is  applied  to 
the  system  there  should 
appear  on  the  top  of  the  TV 
screen  "Read  8080 
INITIALIZE  Cassette."  If 
this  message  appears,  all  is 
well.  The  first  program  on  the 
audio  cassette  furnished  with 
the  kit  is  loaded  in  the  re- 
corder* At  the  start  of  the 
mark  frequency  tone  the 
"Reset"  button  on  the  com- 


79 


2 


SPECIFICATIONS: 


I  III  iriTI  :1 1  i  111  1 1!  11  IfM  II E 


8K  SC  -  8  Specifications: 


Access  Time: 


Current  Req 


emory  Chip: 


Voltage  Supply: 
Battery  Standby: 


500  ns  Max,  (225  max 

on  request) 

Less  than  200  ma  per 
1024  words  maximum 

AMD    91L02   APC    (low 
power  IK  x  1) 


+  5  to   +10 


Address  Select; 


1.5  to  2  Volt, 
Automatic  power 
loss  sensing   circuit. 
Eliminates  need  for 
switches. 

8  ea.  Spst.  switches 
in  a  Dip  IC  package 
(No  longer  any  need 

for  a  soldering   iron 
to  change  address,) 

+  5  Volt   regulated:      4  ea.  7805  regulators 

with  individual  heat 
sinks  to  run  cooler. 


Waft  States: 


NONE!  Your  wait  light 
will  not  burn  because 
of  a  memory  waft 
state, 


ALL   ADDRESS,     CONTROL,    AND   DATA 
OUT   LINES   FULLY  BUFFERED 

Circuit  Board 

Double  sided,  G10  glass  epoxy  board 
Plated  through  holes.  5  mil  tin  minimum 
Solder  reflow  processed 
Solder  mask  on  both  sides  of  PC  board 
Component  lay  out  silk  screened  on 

component  side  of  PC  board 
Gold  plated  edge  contacts 
No  Jumper  wires  used 
Professional  layout  techniques  used 


ALL   ADDRESS,    CONTROL,    AND    DATA    OUT    LINES 

FULLY   BUFFERED 

QUANTITY,    DEALER,    AND   CLUB    INQUIRIES   INVITED 

PLUG    IN-COMPATIBLE  WITH  ALTAIR'    AND   IMSAI* 

IC  SOCKETS  INCLUDED 
$295.00  Kit  -  S394.00  Assembled  —  $2.00  Shipping  and  handling 


•LIMITED  TO  CAPACITY  OF  STANDBY  BATTERY 


111 


SEALS 


ELECTRONICS 

BOX  11651,  KNOXVILLE,  TN.  37919 


Special 


FOR 


£ 


READERS  ONLY 


WITH  EVERY  PRE-PAID  ORDER  OF  $500  OR 
MORE,  WE'LL  GIVE  A  Til  200  CALCULATOR 
ABSOLUTELY  FREE. 

ORDERS  IN  BY  THE  10TH  OF  DECEMBER 
WILL  ARRIVE  IN  TIME  FOR  CHRISTMAS. 

TWX  #810-583-0075 


2>4 


(EfjrtatmaB 


fam  all  nf  «h 

at 

liiDtllLiDiii 

ELECTRONICS 


BOX  11651,  KNOXVILLE,  TN.  37919 


DEALERS  &  DISTRIBUTORS* 


Mr.  Peter  Bickerdike 

CHANNEL  RADIO  &  ELECTRONICS 
18  East  Ortega  Street 
Santa  Barbara    CA    93101 
Phone;  805  965  8551 

THE  COMPUTER  MART 
314  5th  Avenue 
New  York    NY    10001 
Phone:  212  279-7757 

THE  DATA  DOMAIN 
1  11  South  CoJtege 
Btoorrungton    IN    47401 
Phone:  812  334-3607 

THE  COMPUTER  MART 
625  W.  KateNa  Avenue,  #10 
Orange    CA    92667 
Phone:  714  633  1222 

*  COMPUTER  MART 
DISTRIBUTING  COMPANY 
Orange    CA 
714-633-4634 

THE  COMPUTER  MART 
1097  Lexington 
Waitham    MA    021 54 
Phone:  617  890  0677 

THE  COMPUTER  MART 
151   Kline  Blvd. 
Colonia    NJ   07067 
Phone:  201   574-2173 

*  HOBBYTRONIC  DISTRIBUTORS 
1218  Prairie  Drive 
Bloomington    IN    47401 

Phone:  81  2-336  6380 

*  MJB  RESEARCH  &  DEVELOPMENT 
36  W.  62nd  Street 

New  York    NY    10023 

Phone:  21 2-245-8530 

*  MCED  COMPANY 

Suite  101.  1600  Hayes  Street 
Nashville    TN    37203 
Phone:  615  329-1979 


81 


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puter  is  depressed  for  a 
moment.  The  computer  then 
begins  to  accept  the  digital 
data  recorded  on  the  tape.  As 
the  data  is  loaded  into  the 
computer,  the  TV  screen  will 
display  lines  of  a  running 
series  of  numbers  beginning 
with  1  through  7,  and  back  to 
0  through  7,  until  the  pro- 
gram is  loaded.  This 
represents  each  page  of  pro- 
gram data  being  loaded  into 
memory.  At  the  end  of  the 
program  tape,  the  mark  tone 
will  return  and  the  screen  will 
display  "8080  OP  SYSTEM" 
and  the  options.  Selecting 
item  4  of  this  listing  (hit  key 
4)  will  permit  the  operator  to 


begin  generating  a  program 
from  the  keyboard  beginning 
at  page  6.  Program  develop- 
ment using  this  tape  will  be  in 
the  octal  code  format.  Other 
prerecorded  programs  on  the 
tape,  such  as  the  "Memory 
Check,"  are  used  to  deter- 
mine if  all  of  the  memory  tCs 
are  OK.  The  tape  for  that 
program  is  loaded  and  key  6 
is  depressed.  The  TV  screen 
goes  blank  until  all  the 
memory  chips  are  tested. 
Then,  if  all  is  OK,  an  alpha 
sign  appears  in  the  upper  left 
hand  corner  of  the  screen  and 
another  run  is  automatically 
begun.  Each  successful  test 
provides  another  alpha  figure 


on  the  screen.  For  the  2K 
memory  the  check  time  is 
just  a  few  seconds;  for  the 
10K  memory  it  takes  about  a 
minute  to  run  the  test.  If  a 
defective  memory  IC  is 
located,  it  will  stop  the  lest 
and  print  on  the  TV  screen 
which  IC  is  defective  and  on 
which  circuit  board  the  IC  is 
located.  This  really  works>  as 
I  tried  some  known  bum 
chips  and  it  located  them 
very  promptly. 

At  first  I  was  very  appre- 
hensive about  pushing  that 
"RESET"  button,  or  switch- 
ing off  the  power  to  clear  the 
memory  for  a  new  program 
entry,    but   after   a   while    I 


found  that  it  did  not  damage 
the  machine,  I  became  more 
confident  of  the  machine  and 
its  operation. 

Operation 

The  Digital  Group  has 
established  a  branch  called 
The  Digital  Group  Software 
Systems,  which  supplies 
cassettes  of  games  and  other 
items,  such  as  a  Tiny  BASIC 
Extended.5  I  obtained  all  the 
games  (that  are  available  to 
date),  including  the  Tiny 
BASIC  Extended,  Most  of  the 
games  are  written  in  Tiny 
BASIC  and  must  have  the 
Tiny  BASIC  program  loaded 
in  the  computer  before  they 
can  be  played.  The  machine  is 
turned  on,  and  when  the 
i  nitialization  statement 
appears  on  the  TV  screen  the 
Tiny  BASIC  tape  is  loaded. 
Then  the  selected  game  tape 
is  loaded  by  keying  1  on  the 
keyboard  when  the  mark 
tone  appears  at  the  beginning 
of  the  tape. 

The  blackjack  game  is  fun 
to  play,  and  some  of  the 
locally  trained  (Las  Vegas) 
experts  tell  me  it  is  a  very 
well  written  program.  It  has 
all  of  the  game's  rules  well 
executed.  I  condensed  all  of 
my  games  onto  two  tapes.  I 
recorded  the  Tiny  BASIC 
program  at  the  beginning  of 
each  tape  and  then  recorded 
around  10  to  12  games  on 
each  tape.  There  is  still  plenty 
of  tape  left  tor  additional 
g^mes.  The  magnetic  tape 
cassettes  are  of  the  30  to  46 


A 


82 


minute  type.  Longer  tapes  are 
too  thin  to  make  good  re- 
cordings of  digital  data, 

A  new  ham  cassette  is  in 
the  works  at  The  Digital 
Group  Software 
Systems6  and  will  have 
expanded  capability  for  both 
sending  and  receiving  CWand 
RTTY  (with  up  to  8  storage 
slots  of  100  characters  each)* 

1  have  had  some  success  at 
trying  to  program  some 
games  using  the  Tiny  BASIC 
Extended.  (Incidentally,  the 
Tiny  BASIC  Extended  does 
not  have  floating  decimal  or 
square  root  math  capability.) 
I  feel  that  these  programming 
efforts  have  been  the  most 
informative  and  effective  way 
to  learn  just  what  you  can 
and  cannot  do  with  the 
machine.  Also,  you  can  be 
sure  that  it  will  tell  the  oper- 
ator when  he  has  goofed,  in 
no  uncertain  terms. 

Conclusions 

The  construction  of  the 
microcomputer  turned  out  to 
be    no    more   difficult    than 


most  SSTV  construction 
projects.  The  biggest  problem 
is  acquiring  an  understanding 
of  the  machine  and  learning 
the  Tiny  BASIC  Extended 
language.  Computer  terminol- 
ogy is  almost  like  listening  to 
a  foreign  language.  I  can 
assure  the  reader  that  after 
continued  exposure  to  this 
new  technology  the  terms 
and  functions  will  begin  to 
make  sense.  I  should  also  like 
to  warn  the  reader  that  this 
machine  is  addictive.  You  will 
find  yourself  sitting  in  front 
of  that  keyboard  for  hours 
trying  out  first  one  thing, 
then  another.  It  is  absolutely 
fascinating.  Try  it,  and  see  for 
yourself.  ■ 

References 
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Fig.  3„  (a)  TV  circuit  before  modification,  (b)  TV  circuit  after 
modification. 


*  * 


Build  This  Exciting  New 
TVT/'  Louis  Button,  73  Maga* 
zine,  March,  1976. 

2  The    Digital    Group,     PO     Box 

6528,  Denver  CO  80206. 
x 
The    cost    breakdown    for    the 

system's  major  components  is  as 

follows;    8080-4BD    four    board 

system  with    10K  RAM  -  $625; 

TV  set  (new  ICMart  unit,  12  inch 

solid  state)  —  S69;  surplus  key- 


board    with    ASCII    output,    less 

cabinet  -  $49  {plus  chipF  $10); 

tape  recorder,  Panasonic  SUPER - 

SCOPE,    model    CM  04    -   $119; 

power  supply,  cabinet,  fan  —  junk 

box  surplus, 
4 

Television      interface/'      Don 

Lancaster,  BYTE  Magazine,  Octo- 
ber, 1975. 

The  prerecorded  cassette  pro- 
grams and  games  are  sold  by  The 
Digital  Group  Software  Systems, 
Inc,  The  game  cassettes  with  soft- 


ware are  S5  each.  The  Tiny 
BASIC  Extended  program  with 
software  instructions  is  $5.  The 
Educator  tape  for  the  8080 
system  with  software  instructions 
is  $10.  There  is  a  Ham  cassette 
with  software  instructions  tor  $5. 
It  provides  Baudot  RTTY  send 
and  receive,  and  also  CW  send  and 
receive. 

Digital  Group  Software  Systems 
Inc,  PO  Box  1086,  Arvada  CO 
80001 . 


Not  just  a  pretty  face: 


Morrow's  presents  a  front  panel  with  brains—  $249.95 


Combination  front  panel  and 
CPU  board  speeds  program 
development  and  debugging 

Replaces  and  upgrades  ALTAIR/ 
IMSAI  front  panel  and  CPU 
boards ,  or  forms  the  nucleus 
of  a  custom  system. 

This  isn't  a  toy... or  a  con- 
versation piece... but  a  tool 
for  serious  program  develop- 
ment, rivalling  the  sophisti- 
cation of  many  minicomputer 
systems.  Granted  no  system 
can  make  bugs  go  away :  but 
this  one,  finally »  makes  chem 
manageable. 

Two  exclusive  operating  fea- 
tures give  control  over  real 
time,  allowing  you  to  work  on 
a  program  while  it's  running. 

The  "Control  Halt"™  feature 
uses  a  subtle  blend  of  hard- 
ware and  software  to  accom- 
plish the  following: 

•  Refuses  to  let  the  3080A  go 
dormant  after  a  HALT  command, 

•  Examine  and  alter  all  pro- 
cessor registers ♦, .memory  lo- 
cations ..  .and  1/0  ports. 

•  Start,  stop,  and  step  pro- 
grams either  via  a  HALT  in- 
struction or  the  front  panel.   CJ^ 


"   M 


■m  - 


|  .  I 


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0    m    # 
r. . 


o  o  © 

o  o  o 


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iiiiijutiiii  j  jijiii  in  ili  j  j  1 1 1  m  jii  j  i  mil  j  1 1 1 


The  "Slow  Step"™  mode  allows 
you  to  run  through  a  program 
at  a  variable  rate  from  1  to 
65 j 000  steps  per  minute.  The 
display  indicates  the  program 
counter  and  a  processor  regis- 
ter of  your  choice. 

Unambiguous  readouts  replace 
blinking  LEDs ;  a  12  pad  key- 
board replaces  time-consuming 
toggle  switches,  And  because 
the  front  panel/CPU  is  Altair 
buss  compatible,  you  can  build 
a  custom  svstem  around  this 
board  using  Altair  compatible 
peripherals.  Also  compatible 
with  any  software  written  for 
an  Altair  type  buss. 


We've  made  some  strong  claims 

in  this  ad and  given  the 

way  some  companies  advertise, 
you  have  a  right  to  be  skep- 
tical. In  order  to  dispel  any 
doubts,  we've  put  together  a 
complete  documentation  packet 
(schematic,  layout,  software, 
assembly  instruct ions ),  avail- 
able for  $5.00  postpaid.  You 
may  be  surprised  to  find  out 
we've  understated  our  case. 

BOX  6194 

ALBANY, 

iCA  94706, 


■ 


.«■> 


WSwwSSS 


83 


Dr.  Lance  A.  Leventhal 
Emulative  Systems  Co 
J 38  So,  Acacia  Avenue 
Solana  Beach   CA   9207S 


What's  All  This 

LSI  Bunk? 


-  -  an  ostrich's  eye  view 
of  the  microprocessor 


Fig.  I.  The  MITS  Affair  8800,  the  first  home  computer  (courtesy  afM/TS,  fncj. 


Last  year  a  small  com* 
pany  called  MITS  intro- 
duced a  new  product  that 
may  eventually  be  as  exciting 
as  the  first  crystal  radio,  first 
FM  receiver,  or  the  first  tele- 
vision  set.  The  product  was  a 
computer  in  kit  form  that 
cost  less  than  $500.  Fig.  1 
shows  the  completed  version 
of  the  MITS  Altai r  8800,  In 
this  article  we  will  explore 
how  such  inexpensive  com- 
puters became  possible  and 
how  we  can  use  these  new 
devices.  The  science  fiction 
dream  of  a  home  computer 
has  become  real;  already 
hobbyist  clubs  and  stores  that 
specialize  in  home  computers 
have  sprung  up  across  the 
country.  The  world  of  com- 
puters, which  was  formerly 
only  open  to  large  institu- 
tions and  specially  trained 
experts,  has  suddenly  become 
open  to  anyone  with  some 
time  and  some  space  in  a 
house  or  garage. 

Let's  start  at  the  beginning 
{last  year!).  How,  in  these 
days  of  75 tf  loaves  of  bread 
and  $3500  Volkswagens,  can 
a  computer  cost  less  than 
$500?  In  fact,  prices  for  com- 
puters and  such  items  as 
printers,  television  displays, 
and  extra  memory  continue 
to  go  down.  We  can  now  buy 
computers  and  the  devices 
that  go  along  with  them  from 
many  sources  for  prices  that 
seem  incredible. 

The  main  reason  for  these 
developments  is  the  emer- 
gence of  large-scale  integra- 
tion (LSI)  in  semiconductor 
technology.  Fig,  2  shows 
some  of  the  developments  in 
large-scale  integration  in  the 
last  ten  years.  Manufacturers 
can  now  place  the  equivalent 
of   10,000   transistors   on   a 


84 


piece  of  silicon  less  than  a 
quarter  of  an  inch  square;  this 
number  has  doubled  each 
year  for  the  last  ten  years  and 
is  likely  to  continue  doing  so 
for  the  next  ten  years.  LSI 
has  already  led  to  the  elec* 
tronic  calculator  and  the  elec- 
tronic watch-  In  the  early 
1970'$,  semiconductor  manu- 
facturers found  it  possible  to 
place  circuitry  that  would 
perform  all  the  functions  of 
the  central  processing  unit 
(CPU)  of  a  computer  on  one 
or  a  few  chips.  We  call  such 
computers  on  a  chip  micro- 
processors, Fig.  3  is  a  photo- 
micrograph of  the  Motorola 
6800,  one  of  the  most  popu- 
lar microprocessors;  note  the 
tremendous  amount  of  detail 
present  in  a  device  with  an 
area  of  less  than  one  twenty- 
fifth  of  a  square  inch.  Almost 
two  years  of  work  goes  into 
the  design  and  testing  of  such 
a  device;  however,  once 
designed,  the  chips  can  be 
produced  at  the  rate  of 
thousands  per  hour  for  a 
manufacturing  cost  of  a  few 
cents  apiece. 

A  Brief  Historical  Perspective 

The  main  reason  for  the 
low  price  of  hobby  com- 
puters is  the  use  of  micro- 
processors, A  microprocessor 
will  fetch  instructions  from 
memory  and  decode  them, 
accept  data  from  memory  or 
outside  sources,  perform 
arithmetic  or  logical  opera- 
tions and  save  the  results  in 
memory  or  send  them  to 
external  displays  or  other 
devices.  A  microprocessor 
will  thus  do  everything  that  a 
large  central  processor  will 
do,  even  those  which  are  the 
heart  of  enormous  computers 
like  the  IBM  370,  Burroughs 
6700,  or  Control  Data  7600. 
Yet  the  microprocessor  is 
built  on  one  or  a  few  chips  of 
silicon  and  costs  only  $10  to 
$100, 

The  microprocessor  is  an 
outgrowth  of  MOS  LSI  tech- 
nology, MOS,  metal  oxide 
semiconductor,  is  the  name 
for  a  device  fabrication 
process  which  j  I  lows  very 
complex  devices  to  be  placed 
on   a  single   chip.  The  MOS 


LSI  technology  uses  masking 
processes  which  we  can  com- 
pare to  those  used  in  photo- 
graphy. The  manufacturing 
cost  of  MOS  LSI  devices,  like 
the  developing  costs  of 
photographs,  is  relatively 
independent  of  the  amount 
of  detail  involved.  The  cost  of 
developing  a  picture  with  a 
million  precise  details  is  the 
same,  in  terms  of  paper  and 
chemicals,  as  the  cost  of 
developing  a  picture  taken 
without  removing  the  lens 
cap-  Of  course,  the  more 
detailed  photograph  requires 
a  better  camera,  more  atten- 
tion to  layout,  and  greater 
photographic  skill;  it  is  also 
less  likely  to  turn  out  cor- 
rectly. The  production  of 
complex  MOS  LSI  chips  is 
similar  to  the  development  of 
detailed  photographs.  Since 
the  production  cost  of  a  com- 
plex chip  is  not  markedly 
different  from  that  of  a 
simple  chip,  the  more  that 
can  be  placed  on  a  single 
chip,  the  cheaper  the  overall 
system  will  be.  Such  a  single- 
chip  system  will  require  fewer 
packages  and  connectors,  less 
power,  less  labor,  and  a 
smaller  amount  of  other  sup- 
porting circuitry  and  equip- 
ment. LSI  thus  results  in 
lower  total  cost  if  we  can  use 
the  same  LSI  devices  over  and 
over  again,  LSI-based  systems 
will  also  be  smaller,  cheaper 
to  run,  and  more  reliable. 

MOS  LSI  techniques  were 
first  used  to  create  compact, 
low  power  memories.  In  the 
late  1960rs,  these  techniques 
were  used  to  create  electronic 
calculators;  the  first  such 
devices  were  multi-chip 
systems  which  retailed  for 
several  hundred  dollars  but 
could  do  little  more  than 
today's  $10,00  or  $15,00 
devices.  Remember  that  just 
ten  years  ago  the  large 
mechanical  calculator  and  the 
slide  rule  were  the  state  of 
i he  art.  In  the  early  1970's, 
the  quickly  changing  calcula- 
tor market  made  semicon^ 
due  tor  manufacturers  look 
for  new  ways  to  produce 
more  general  and  more  flex- 
ible devices  which  could  be 
produced    in    large    volumes 


Manufacturer 

The  Digital  Group 

Denver,  Colo. 
E  and  L  Instruments 

Derby,  Conn. 
EBKA  Industries  Inc. 

Oklahoma  City,  Ok  la. 
Electronics  Product  Associates,  Inc. 

San  Diego,  Calif. 
Gnat  Computers 

San  Diego,  Calif, 
IMS  Associates 

San  Leandro,  Calif. 
Infinite  Inc. 

Cape  Canaveral,  Fla. 
Martin  Research 

Nonhbrook,  I II, 
MITS 

Albuquerque,  Mew  Mex. 
MOS  Technology 

Norrisiown,  Pa* 
Mycro-Tek 

Wichita,  Kan. 
Ohio  Scientific  Instruments 

Hiram,  Ohio 
Pen  a  co  Corp. 

Los  Altos,  Calif , 
PCM  Corp. 

San  Ramon,  Calif. 
Polymorphic  Systems 

Goleta,  Calif, 
RCA 

Sorrier vi lie,  N.J. 
Southwest  Technical  Products 

San  Antonio,  Texas 
Sphere  Corp. 

Bountiful,  Utah 
Wave  Mate 

Gardena,  Calif. 


Microprocessor  Used 

Intel  8080.  Zilog  ZSO,  Motorola 

6800.  8i  MOS  Tech  6502 
Intel  8080 

MOS  Technology  6502 

Motorola  6800 

Intel  8080 

Intel  8080 

RCA  COSMAC 

Intel  8080 

Intel  8080 

Motorola  6800 

MOS  Technology  6502 

Intel  8080 

MOS  Technology  6502 

Motorola  6800 
MOS  Technology  6502 

Intersil  6100 

Intel  8080 

RCA  COSMAC 

Motorola  6800 

Motorola  6800 

Motorola  6800 


Table  L  Manufacturers  of  educational  and  hobby  microcom- 
puters. Note:  Many  of  the  largest  manufacturers  of  micro- 
processors and  microcomputers  are  not  included  in  this  list 
because  their  products  are  intended  for  industrial  applications. 


and  yet  could  be  modified  by 
the  calculator  manufacturers 
to  meel  new  or  custom  re- 
quirements. 

The  first  microprocessor, 
the  Intel  4004,  was  developed 
for  a  calculator  manufacturer. 
Although  it  was  designed 
primarily  for  the  calculator 
market,  it  was  programmable; 
its  actual  functions  could  be 
changed  by  the  calculator 
ma  n  u  faclurer  rather  than 
being  fixed  by  the  semicon- 
ductor manufacturer.  The 
power  of  the  microprocessor 
and  its  advantages  over  hard- 
wired design  soon  became 
evident  to  other  industries. 
The  first  3  bit  microprocessor 
(the  Intel  8008},  directed 
largely  toward  manufacturers 
of  computer  terminals,  was 
introduced  in  1971 . 

The  complete  history  of 
the  microprocessor  is  thus 
only  five  years  long.  Already, 
though,     processors     are     in 


common  use  which  are  a 
hundred  times  as  powerful  as 
the  early  4004  and  8008; 
such  processors  can  do  more 
than  could  large  computers  of 
15  years  ago  which  cost  (in 
uninflated  money)  over 
$100,000.00.  Nor  have  we 
yet  come  close  to  reaching 
the  limits  of  microprocessor 
performance]  many  ol 
today's  limitations  will 
disappear  as  manufacturers 
continue  to  produce  more 
complex  LSI  chips, 

A  Microprocessor  Survey 

Let's  take  a  look  at  some 
of  the  existing  microproces- 
sors from  the  hobbyist's 
point  of  view.  We  will  pay 
particular  attention  to  those 
microprocessors  which  are 
widely  used  as  central 
processing  units  in  hobby 
computers. 

Cur  rent  microprocessors 
can    be    divided    into    three 


85 


Fust 

First 

First 

F  ifst 

a 

Intel 

Motorola 

Memory 

Multi-chip 

Singte-chip 

Microprocessor 

8080 

6800 

Chips 

Calculators 

Calculators 

t Intel  4004) 

f25G  bits) 

1  K  Memory 
Chips 

4K  Memory 
Chips 

1 GK  Memory 
Chips 

1966 


1968 


1970 


1971 


1973 


1974 


1975 


Fig,  2.  LSI  developments  from  1966  to  the  present. 


basic  categories: 

(1  )  Calculator-like 
processors 

(2)  Standard,  self-con- 
tained processors  with  a 
fixed  instruction  set 

(3)  Bit-sliced  proces- 
sors and  others  with  a 
user-defined  instruction 
set 

The  three  categories  include  a 
wide  range  of  computing 
power,  speed,  price,  and 
application  areas.  Category  2 
contains  atl  of  the  micro- 
processors used  in  hobby 
computers.  Therefore,  we  will 
briefly  describe  categories  1 
and  3  and  focus  our  attention 
on  category  2. 

Category  1,  the  calcu- 
lator-like processors,  contains 
the  simplest  and  cheapest 
devices,  Typical  processors  in 
this  category  are  the  Intel 
4004  and  4040,  Rockwell 
PP5-4,  Texas  Instruments 
TMS-1000,  American  Micro- 
Systems  9209,  and  National 
SC/MP.  Many  of  these 
devices  are  much  like  calcu- 
lators; they  are  often 
specially  designed  or  have 
special  instructions  to  handle 
keyboards  and  lighted  dis- 
plays and  to  perform  simple 
decimal  arithmetic.  However, 
these  microprocessors  are 
user-programmable  (unlike 
calculator  chips)  and  can  be 
used  in  a  wide  variety  of 
applications.  Besides  ad- 
vanced calculators,  such 
devices  have  been  used  in 
character  printers,  games, 
household  appliances,  paper 
tape  readers,  test  sets,  func- 
tion generators,  counters, 
microfilm  readers,  tele- 
phones, tuners,  valves,  scales, 
cash  registers,  and  time  and 
attendance  terminals.  We  may 
have  hundreds  of  these 
devices  in  a  single  store,  fac- 
tory, or  laboratory, 

The  devices  of  category  1 
represent  the  smallest  amount 


of  computing  power  that  can 
be  purchased  as  a  single  unit. 
Complete  systems  based  on 
these  devices  cost  only  $5  to 
$30  in  large  quantities.  They 
are  used  mainly  in  applica- 
tions requiring  low  cost,  low 
speed,  and  relatively  limited 
processing  power*  Such 
microprocessors  are  most 
often  found  in  large  volume 
applications  as  simple  con- 
trollers for  systems  whose 
speed  is  limited  by  human 
interaction  or  slow  mechani- 
cal devices.  These  processors 
generally  have  very  short 
word  lengths  (most  can  only 
handle  4  bits  at  a  lime)  and 
are  thus  unsuited  to  systems 
requiring  complex  calcula- 
tions, high  data  rates,  or  great 
accuracy*  Although  these 
simple  processors  do  not 
attract  much  attention  from 
writers  or  researchers,  they 
are  still  probably  the  most 
widely  used  in  terms  of 
volume  because  of  their  low 
cost. 

We  should  note  that  com- 
puter speed  is  relative.  We 
often  call  a  computer  slow  if 
it  can  only  execute  100,000 
instructions  a  second!  A  large 
computer  may  be  able  to 
execute  10,000,000  instruc- 
tions in  that  same  time  but 
the  "slow"  computer  still 
seems  to  work  at  lightning 
speed  to  the  average  observer. 

Category  3,  the  bit-sliced 
processors,  are  largely  in- 
tended as  building  blocks  for 
special -purpose  computing 
elements.  Typical  micro- 
processors in  this  category  are 
the  National  IMP,  Intel  3000, 
Advanced  Micro  Devices 
2900,  Monolithic  Memories 
6701,  Texas  Instruments 
SBP0400,  and  Fairchild 
Macrologic.  Unlike  the 
devices  in  categories  1  and  2, 
the  bit-sliced  processors  are 
not  self-contained  CPUs, 
Rather,  they  involve  a  whole 


family  of  elements  including 
a  2  or  4-bit  processor  slice 
which  the  user  must  combine 
to  form  a  CPU.  Such  a  CPU 
will  generally  involve  30  to 
50  discrete  packages.  These 
microprocessors  are  thus 
intermediate  between  the 
self-contained  CPUs  and  the 
discrete  circuitry  that  is  cur- 
rently used  to  make  large 
computers. 

Most  of  the  bit-sliced 
processors  are  much  faster 
than  standard  micro- 
processors, but  significantly 
more  expensive  and  harder  to 
use.  CPUs  based  on  these 
processors  typically  cost 
$500  to  $1500,  Typical  appli- 
cations include  disk  con- 
trollers, minicomputer  CPUs, 
test  equipment,  intelligent 
terminals,  and  signal 
processing  equipment.  In  the 
near  future,  the  bit-sliced 
processors  may  become  the 
basis  for  most  minicom- 
puters. However,  the  cost  and 
the  number  of  elements  re- 
quired for  a  CPU  will  have  to 
be  significantly  reduced 
before  such  devices  can  be 
used  in  hobby  computers. 

The  main  category  of 
microprocessors  with  which 
hobbyists  are  presently  con- 
cerned is  category  2,  the  stan- 
dard, self-contained  proces- 
sors with  a  fixed  instruction 
set*  These  processors  are 
intermediate  in  performance 
between  calculators  and  mini- 
computers (i.e.,  between  cate- 
gories 1  and  3).  They  are 
complete  CPUs  on  one  or  a 
few  chips  and  require  only  a 
small  amount  of  supporting 
circuitry.  Prices  range  from 
$20  to  $200  in  single  quan- 
tities (not  including  memory, 
I/O,  or  other  system  require- 
ments). Most  of  these  devices 
will  handle  8  bits  of  informa- 
tion at  a  time,  although  a  few 
can  handle  16  bits  at  once. 
The  most  widely  used  micro- 


processors among  hobbyists 
are; 

Intel  8080  (the  Intel  8008  is 
an  older,  less  powerful  ver- 
sion) 

The  Intel  8080  was  the 
first  device  in  this  category  to 
be  introduced  (in  1973)  and 
is  the  most  widely  used  CPU 
in  hobby  computers.  It  fs 
used  in  the  M ITS  Altair  8800, 
IMSAI  8080,  and  in  similar 
sets  from  Martin  Research 
and  other  sources.  The  Zilog 
Z-80  is  an  extended  version 
of  the  Intel  8080  with  a 
larger,  more  powerful  instruc- 
tion set  and  other  extra 
features. 
Motorola  6800 

The  Motorola  6800  is 
comparable  to  the  Intel  8080 
in  performance  (it  was  first 
introduced  in  1974).  It  is 
used  in  the  MITS  Altair  680 
and  other  hobby  sets  from 
Southwest  Technical  Pro- 
ducts, Sphere,  Wave  Mate, 
and  Ohio  Scientific  Instru- 
ments. 
MOS  Technology  6502 

The  MOS  Technology 
6502  is  also  comparable  to 
the  Intel  8080  and  Motorola 
680O  in  terms  of  perfor- 
mance. It  was  first  introduced 
in  1975  and  is  used  in  the 
JOLT  hobby  computer  and 
others.  The  MOS  Technology 
6502  is  somewhat  cheaper 
than  either  the  Intel  8080  or 
Motorola  6800,  but  not  as 
widely  used. 
National  PACE 

The  National  PACE  is 
slower  than  any  of  the  pre- 
viously mentioned  processors 
and  somewhat  more  expen- 
sive. It  will,  however,  handle 
16  bits  of  information  at  a 
time  (the  others  handle  8) 
and  has  a  more  powerful 
instruction  set.  Systems  based 
on  this  processor  are  available 
from  Godbout  Electronics 
and  from  Hamilton-Avnet 
{the  Pacer), 


a 


86 


101  Baste 
Computer  Games 

David  H.  AM  An  anthology  of  games 
and  simulations —from  Aeev*I>euccy  1o 
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Large  formal.  158  pp.  56,95  [gA] 

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with  the  Computer 

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With  the  Computer, 
2nd  Ed. 

Donald  Spencer.  Over  70#tmes+  puzzles* 
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^^ 


M  i  coprocessors 

A  co licet  ion  of  articles  from  Electronics 
magazine.  The  book  is  in  three  parts: 
device  technology;  designing  with 
microprocessors:  and  applications.  160 
pp.  1975  S 1 3.50  [9J] 


Microprocessors:  Tech- 
nology, Architecture 
and  Applications 


Tom    Dwyer   and    Michael   Kaufman. 

Ted  Nelson.  This  book  is  devoted  to  the  **This  is  a  fine  book,  mainly  for  young 

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stand  computers.  In  a  blithe  manner  the  detail,      many     examples     (including 

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aires,       binary      patterns,      computer  thought  having  been  given  to  the  use  of     describes  the  related  computer  structures 

architecture,  mini-computers,  big  com-  graphics  in  teaching*  This  is  the  best  of     and  electronic  semi -conduct  or  processes. 

ptttcri,     microprocessors,     simulation,  I  he   introductory  texts  on   BASICS—     Treats    both   hardware   and   software, 

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Daniel  ft,   McGlynn.  This  introduction 
to     the    microprocessor     defines    and 


Whole  earth  catalog  style  and  size.  A 
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Computer  Power  and 
Human  Reason 

Joseph  Weizenhaum*  in  this  major  new 
book,  a  distinguished  computer  scientist 
sounds  the  warning  against  the 
dangerous  tendency  to  view  computers 
and  humans  as  merely  two  different 
kinds  of  "thinking  machines"  Weizcn- 
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BASIC  Programming 
2nd  Ed 

Kemenv  and  Kuru.  **A  simple  gradual 
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giving  an  overview  of  commercially 
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Creative  Computing 
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Artist  and  Computer 

Ruth  Leaviit,  ed.  Presents  personal 
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Computer  Science: 

A  First  Course  (2nd  Ed,) 

Forsythe.  Keenan.  Organic  k.  and 
Stenherg.  A  new,  improved  edition  of 
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Mr.  Spock  Poster 

Dramatic,  large  (17"  x  23")  computer 
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CREATIVE  COMPUTING,  DeptT 
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Intersil  6  J  00 

The  Intersil  6100  is  a  new 
device  which  executes  all  the 

instructions  of  the  world's 
most  popular  minicomputer, 
Digital  Equipment  Corpora- 
tion's PDP-8.  The  advantage 
of  the  Intersil  processor  is 
that  a  tremendous  number  of 
programs  are  already  available 
for  ihe  PDP-8,  Systems  based 
on  this  processor  can  be 
obtained  from  PCM  Corp.  or 
Ohio  Scientific  Instruments. 
Other  processors  in  cate- 
gory 2  which  may  eventually 
be  used  in  hobby  computers 
include  the  Rockwell  PPS-8, 
Signetics  2650,  RCA  CDP 
1802  (COSMAC),  Fair  child 
F-8,  and  General  Instrument 
CP-160Q.  Table  1  contains  a 
list  of  some  manufacturers  of 
hobby  computers  and  the 
processors  they  use.  A  new 
entry  in  this  category  is  the 
Texas  Instruments  TMS9900 
which  handles  16  bits  at  a 
time  like  the  National  PACE 
but  is  just  as  fast  as  the  Intel 
8080  or  Motorola  6800,  The 
TMS9900  is  presently  more 
expensive  (about  $200  in 
single    quantities)    than    the 


other  microprocessors  men- 
tioned above,  but  offers 
much  more  processing  power. 

Of  course,  the  devices  in 
category  2  have  found  many 
applications  besides  hobby 
computers.  Among  the  more 
common  are  monitoring 
systems,  line  printers,  naviga- 
Hon  systems,  business 
machines,  test  equipment, 
security  systems,  program- 
mable terminals,  plotters, 
oscilloscopes,  machine  tools, 
Industrie  I -control  systems, 
message  switching  units, 
graphics  terminals,  and 
medical  instruments.  These 
processors  will  probably  con- 
tinue to  have  the  widest 
variety  of  applications  in  the 
near  future. 

Semiconductor   Technologies 

Now  let's  examine  the 
characteristics  of  the  semt- 
conductor  technologies  from 
which  microprocessors  are 
produced.  The  importance  of 
particular  features  will  be 
described  as  well  as  techno* 
logical  trends  that  may  be  of 
significance  to  hobbyists. 

The     First    question    that 


must  be  answered  is,  "What 
characteristics  are  desirable  in 
a  semiconductor  tech- 
no I  ogy?*'  Some  desirable 
characteristics  are  fairly 
obvious; 

Low  cost:  If  devices  from 
a  particular  technology  can 
be  produced  cheaply,  the  ulti- 
mate cost  will  be  lower.  Cost 
depends  on  the  complexity  of 
the  semiconductor  processes 
and  on  the  amount  of  ex- 
perience that  has  been 
acquired  with  a  particular 
process.  We  should  note  that 
semiconductor  prices  vary 
widely  and  manufacturers* 
list  prices  often  don' l  closely 
follow  the  actual  prices 
charged  by  distributors  or 
supply  houses. 

High  Density;  If  more 
complex  circuits  can  be 
placed  on  a  single  chip,  fewer 
devices  will  be  needed  to  per- 
form useful  functions.  More 
complex  chips  are  not  usually 
much  more  expensive  to  man- 
ufacture, but  require  fewer 
packages,  fewer  connections, 
less  board  space,  and  less 
power  than  a  larger  number 
of  simple  chips. 


Fig.  3.  A  Photomicrograph  of  the  Motorola  6800  microprocessor  (courtesy  of  Motorola  6800 
Semiconductor  Products^  IncJ, 


Low  power  consumption; 
If  the  circuits  produced  from 
a  particular  technology  re- 
quire less  power,  they  will 
need  smaller  power  supplies, 
use  less  energy,  and  produce 
less  heat.  Devices  that  use 
large  amounts  of  power  will 
need  expensive  power 
supplies  and  special  cooling 
mechanisms  such  as  fans  or 
air  conditioning. 

High  speed;  If  the  devices 
run  faster,  they  can  simply 
perform  more  work  in  a  given 
amount  of  time. 

Even  these  simple  charac- 
teristics can't  be  easily  com- 
bined -  devices  that  run  at 
high  speeds  usually  dissipate  a 
lot  of  power,  for  instance. 
Technologies  that  result  in 
high  speed  also  typically 
result  in  low  density  and  rela- 
tively high  cost.  Tradeoffs 
will  have  to  be  made. 

Other  useful  features  in  a 
technology  that  may  not  be 
quite  so  obvious  include: 

Compatibility  with  stan- 
dard TTL  circuitry;  If  devices 
made  from  a  particular  tech- 
nology can  be  readily  used 
with  the  standard  7400  series 
TTL  integrated  circuits,  they 
can  then  be  easily  and 
cheaply  interfaced  to 
peripherals  and  other  cir- 
cuitry. 

Ruggedness:  If  devices 
made  from  a  particular  tech- 
nology are  more  rugged,  they 
will  be  able  to  withstand 
te  mperature  variations, 
moisture,  power  surges,  noise, 
and  shock.  Devices  that  are 
vulnerable  to  various  condi- 
tions will  have  to  be  pro- 
tected by  means  of  special 
circuitry  or  packaging. 

Wide  availability  and 
support:  Technologies  that 
are  produced  by  many 
suppliers  and  heavily  sup- 
ported will  have  more  parts 
available,  more  compatible 
devices,  and  lower  prices. 
Such  a  technology  is  likely  to 
continue  in  use  for  many 
years. 

Standard  parts  and  large 
memories  in  the  same  or  com- 
patible technologies:  Tech- 
nologies thai  have  such 
devices  will  be  relatively  easy 
to  use  in  complete  computer 


systems. 

Microprocessors  are  cur- 
rently available  in  six 
different  technologies: 

PMOS  (^Channel  Metal 
Oxide  Semiconductor):  the 
oldest  MOS  technology;  high 
density  and  low  cost  but  rela- 
tively fow  speed;  not  in- 
compatible. 

NMOS  (N*Channel  Metal 
Oxide  Semiconductor):  the 
present  state  of  the  art  MOS 
technology;  high  density  and 
moderate  cost  and  speed;  can 
be  made  TTL  compatible. 

CMOS  (Complementary 
Metal  Oxide  Semiconductor): 
a  technology  widely  used 
when  low  power  consump- 
tion and  high  noise  immunity 
are  needed;  medium  -  in 
density,  cost,  and  speed;  can 
be  made  TTL  compatible. 

Schottky  TTL  (Schottky 
Transistor- Transistor  Logic): 
a  variation  of  standard  TTL 
i hat  offers  high  speed,  but 
high  power  consumption  and 
cost  and  low  density;  fully 
compatible  with  standard 
TTL, 

ECL  (Emitter-Coupled 
Logic):  A  very  fast  tech- 
nology that  is  very  expensive 
and  consumes  a  large  amount 
of  power;  not  compatible 
with  TTL. 

f2L  ( I  n  tegrated- 1  n  j  ecti  on 
Logic):  a  new  technology 
that  may  ultimately  combine 
the  speed  of  TTL  with  the 
density  of  MOS, 

A  comparison  of  these 
technologies  is  shown  in 
Table  Z  Clearly,  PMOS  and 
NMOS  rank  highest  in  the 
important  categories  of  cost 
and     density,    CMOS    ranks 


Cost  (1  =  Lowest) 
Density  (1  -  Most  Dense! 

Power  Consumption 
(1  -  Least* 

Speed  {1  -  Fastest} 

TTL  Compatibility 

Hugged  nes? 
<1  =  Most  Rugged) 

Availability  and 
Support  (1  -  Most) 

Standard  Paris  end 
Memories  i  1  *  Most ) 


PMOS 

1 


No 


5 


4 


NMOS 
2 

1 

4 
5 

Sometimes 


CMOS 
4 


1 
3 

Sometimes 


Schottky 

TTL 

3 
4 

E 

2 

Ves 


|2L 
6 


2 

3 

7 


ECL 
6 

6 

6 

1 
No 

6 


5 


Table  2    Comparison  of  semiconductor  technologies. 


highest  in  ruggedness  and 
lowest  in  power  consump- 
tion, ECL  Is  the  fastest,  while 
Schottky  TTL  is  the  easiest 
to  interface, 

At  the  present  time, 
NMOS  seems  to  have  the 
most  desirable  combination 
of  characteristics.  It  is  rela- 
tively cheap,  very  dense,  con- 
sumes little  power,  can  be 
made  compatible  with  stan- 
dard TTL  circuitry,  and  has  a 
family  of  large  compatible 
memories.  NMOS  can  be  used 
to  make  single-chip  micro- 
processors which  run  at 
reasonable  speeds.  Such  com- 
monly used  microprocessors 
as  the  Intel  8080,  Motorola 
6800,  MOS  Technology 
6502,  and  Fairchild  F-8  arc 
made  from  the  NMOS 
process. 

Furthermore,  new 
developments  in  the  NMOS 
technology  should  lead  to 
c  onsiderabte  i  mprovemen  ts. 
NMOS  memories  (like  the 
Intel  2115)  are  now  available 
that  are  as  fast  as  memories 


made  from  Schottky  TTL. 
The  maximum  size  of  the 
chips  that  can  be  produced 
from  NMOS  has  also  been 
increased.  New  NMOS 
processes  have  been  intro- 
duced that  can  be  easily  inter* 
faced  with  standard  TTL  cir- 
cuitry and  can  use  standard 
TTL  power  supplies.  Signifi- 
cantly increased  performance 
can  be  expected  in  the  next 
few  years  from  NMOS  micro- 
processors. 

As  for  the  other  tech- 
nologies, the  ones  that  will 
probably  be  the  most  inter- 
esting to  hobbyists  are  CMOS 
and  |2|_.  Only  a  few  proces- 
sors  (most  notably  the  RCA 
COSMAC  and  Intersil  6100) 
are  presently  available  in 
these  technologies,  but  none 
has  been  widely  used  in 
hobby  computers.  However, 
s  i  n  gle-chi  p  microprocessors 
would  appear  to  be  possible 
in  both  technologies  at  rela- 
tively low  prices.  Such 
processors  would  not  only  be 
faster  than  NMOS  processors, 


but  would  also  use  substan- 
tially less  power  and  would 
be  much  more  rugged.  Micro 
processors  and  large 
memories  in  these  technolo- 
gies may  become  available  to 
hobbyists  in  the  next  few 
years.  ■ 

References 

Bylmsky,  G,,  'Here  Comes  the 
Second  Computer  Revolution/' 
Fortune,  November  1974,  p.  134, 
"Computer  Store:  "Frantic  and 
Fun/        Datamation,     November 

1975,  pp.  143-145. 

Gilder,  J.  H.,  "All   About  Micro- 
computers/' Computer  Decisions, 
December  1975,  pp.  44-49. 
Heiser,   R.,  "Hobbyists  off  on  a 
Weeken  d  / r      Da  tarnation ,      M  ay 

1976,  pp.  201  203. 
Himmelfarb,  M.,  "The  Makings  of 
a    Mini/'    Digital   Design,   August 

i975r  p.  ea 

McWhorter,  E.  W.,  "The  Small 
Electronic  Calculator/'  Scientific 
American,  March  1976,  pp. 
88-98. 

Vacroux,  AtG.,  "Microcom- 
put  er  s ,  *  *  Scien  tiftc  A  merican ,  M  ay 
1 975,  pp.  32-40. 

Weisbecker,  J.,  "A  Practical  Low- 
Cost,  Home/School  Microproces- 
sor System/'  Computer,  August 
1 974,  pp.  88^98. 


jsMwrnra 


visiting  views  from  around  the  globe 


from  page  9 

Wednesday  and  said  he  was  told  at  the 
hospital  that  it  did  not  have  the 
proper  equipment  to  treat  Garden, 

By  thai  lime,  Smith  and  other  hams 
had  managed  to  get  Garden's  bail 
reduced  from  $9,000  to  S2J0O.  But 
liter  appeals  on  the  air  only  $1,700 
had  been  pledged. 

When    Johnston    learned    that    the 


courts  in  Mexicali  were  to  dose 
yesterday  for  a  30- day  recess,  he 
decided  to  go  there  and  plead  with 
Judge  Rafael  Moreno  Henrique*,  chief 
justice  of  the  Superior  Tribunal. 

"Why  should  this  boy  lie  there  and 
pay  with  his  life  for  a  minor  crime?" 
Johnston  said  he  asked  the  judge- 
Reduce  the  bail  to  an  amount  the 
hams  could  pay,  Johnston  pleaded, 
The  judge  agreed  to  do  so.  "He  was  a 
fine   gentleman/'   Johnston   said.    He 


added  that  all  government  officials  in 
Mexicali  cooperated  to  the  fullest  to 
free  Garden- 

Johnston,  who  is  coordinating  the 
fund-raising  effort,  said  that  he  had 
only  $22  in  hand  from  pledges  made 
to  htm  over  the  radio. 

The  17  SI 00  bills  used  to  free 
Garden  yesterday  were  supplied  by 
one  ham  who  asked  to  remain 
anonymous.  He  is  confident  that  the 
pledges  will  be  made  good. 

Another  ham  told  Hower  he  would 
make  good  any  shortfall  between  the 
pledges  and  the  bail 

Hower  said  the  hams  are  not 
judging  whether  Garden  is  guilty.  "If 
you  find  a  man  bleeding  in  the  middle 
of  the  road,  you  help  him/'  he  said. 

As  word  of  the  mission  of  mercy 


spread,   Johnston   got   a   call  from  a 
man  in  Oregon  yesterday 

"He  asked  me  if  the  company  that 
rescued  Robert  could  also  save  a  man 
in  Acapulco,"  Johnston  said.  "I  told 
him  that  we  are  not  a  company,  but  a 
fraternal  order  just  trying  to  be  of 
service." 

The  hospital  was  to  check  today  to 
see  if  Garden  is  a  former  serviceman 
ent tiled  to  VA  treatment. 

If  he  is,  about  the  only  reason  he 
could  be  turned  out  of  the  hospital 
and  refused  treatment  would  be  if  he 
had  been  dishonorably  discharged,  a 
hospital  spokesman  said. 

Martin  Gerchen 

Reprinted  from  the  Evening  Tribune 
(San  Diego),  Jufy  16,  1376, 


89 


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'Tarbeir  tapes  and  ICC.  Std.  tapes.  $50.00,  Wired  &  Tested. 

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*NOTE.  You  do  not  require  an  interface  with  the  3M1  and  3M3 
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Record  new  data  on  one  track  and  preserve  three  or  record 
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Rich  Didday 
1218  Broadway 
Santa  Cruz   CA   95062 


Fig,  L  Organization  of  the  "data  bank.  "Each  fife  is  stored  on  an  individual  cassette. 


The  Soft  Art 


of  Programming 


--  part 


(Here's  the  final  install- 
ment of  Rich  Didday  *$  series 
on  BASIC  programming.  The 
article  is  written  around  a 
recordkeeping  program  for 
computer  club  members  «  . . 
but  the  concepts  presented 
will  be  applicable  in  many 
other  areas  as  welL  For  the 
beginner,  a  lot  can  be  learned 
from  reading  and  analyzing 
the  program  —  which  holds 
true  for  experienced  program- 


92 


mers,  too.  I'd  like  to  invite 
you  readers  who  sit  down  and 
develop  the  machine  language 
routines  for  cassette  read  and 
write  to  submit  them  for 
publication,  OK?  —  Ed,) 

What  we  rve  been  doing:  In 
Part  I  we  went  over  ways  of 
learning  the  individual  ele- 
ments of  the  programming 
language  BASIC,  emphasizing 
that  good  programming 
involves  planning  things  out 


long  before  you  ever  write 
any  statements  in  BASIC 
(programming  is  a  lot  more 
than  just  coding).  We  played 
around.  We  had  fun. 

In  Part  II  we  began  to  put 
together  sequences  of  com- 
puter instructions  (BASIC 
statements)  in  order  to  carry 
out  a  substantial,  useful  task 
—  namely,  the  record-keeping 
requirements  of  our  com- 
puter club    We  saw  ways  of 


using  arrays,  ways  of 
est  i  ma  ting  how  much 
memory  our  program  would 

need  for  data  storage,  ways  of 
cutting  down  on  memory 
usage.  We  got  frustrated. 

In  this,  the  concluding 
part,  welt  finish  the  record- 
keeping program  by  pulling 
together  the  ideas  we  laid  out 
fast  time,  with  some  major 
improvements.  We  'II 
emphasize     the     notion     of 


developing  our  program  part 
by  part}  keeping  the  user '5 
convenience  and  our  overall 
objectives  clearly  in  mind. 
We  11  be  satisfied,  ready  to  go 
onward  and  upward. 

At     last!     We  Ye    finally 
ready     to    finish    our 

record-keeping  program. 
Before  plunging  Into  the 
details  of  the  finished  pro- 
gram, let's  be  sure  we  have 
the  big  picture  firmly  in 
mind. 

Fig.  1  shows  the  organiza- 
tion of  our  "data  bank," 
There  is  a  record  for  each 
member.  Each  record  consists 
of  six  fields  which  store 
specific  information  about 
that  member.  A  file  consists 
of  some  number  of  records, 
the  only  restriction  being  that 
the  number  of  records  on  a 
given  fife  can  be  no  more 
than  will  lit  in  memory  at 
once.  We'll  store  each  file  on 
a  separate  cassette  tape,  so 
we'll  use  the  lerms  file,  tape, 
and  tape  file  pretty  much 
interchangeably.  In  addition 
to  the  tapes  storing  member- 
ship records,  there  is  one 
marc  which  stores  a  directory 
which  well  use  to  enable  our 
program  to  decide  which  tape 
file  it  needs  to  find  a  specific 
member's  record.  The  direc- 
tory tape  together  with  the 
membership  record  tape  files 
make  up  the  library. 

Our  program  must 
initialize  and  maintain  the 
library,  calling  for  and  re- 
writing tape  files  as  the  need 
arises  (based  on  the  com- 
mands the  u*cr  gives  a\  the 
terminal).  The  four  com- 
mands ADD,  DELETE,  LIST, 
and  END  seem  sufficient  for 
our  needs.  Fig.  2  describes 
each  command  and  shows  the 
basic  structure  of  the  pro- 
gram. 

So  far,  the  only  difference 
from  last  month's  plan  is  the 
inclusion  of  a  directory.  It  is 
a  big  difference,  though, 
because  the  directory, 
coupled  with  a  more  reason- 
able  way  of  organizing  the 
records  (namely,  keeping 
them  in  alphabetical  order 
instead  of  in  no  order  like  last 


time),  will  make  the  system 

much  more  convenient  to 
use.  For  now,  let's  follow 
through  in  a  "top-down"  way 
and  code  the  main  structure 
of  the  program,  the  part 
shown  in  the  flow  chart  in 
Fig.  2.  We'll  leave  the  details 
for  subroutines  which  well 
work  out  one  by  one.  This 
general  strategy  is  sometimes 
called  "top-down  program- 
ming' and  sometimes 
"modular  programming,"  The 
idea  is  that  by  breaking  the 
problem  down  into  manage- 
able chunks,  you're  less  likely 
to  get  confused,  and  more 
likely  to  keep  all  your  objec- 
tives in  mind  as  you  go. 

The  Main  Program 

The  main  program  begins 
by  declaring  the  arrays  to 
store  membership  records 
(exactly    the    same    as    last 


FLUSH  CUR- 
RENT n    I 
AXO 
aiHECfO*4<       F 


C 


STOP 


Command 
END 


time)  and  the  arrays  which 
hold  information  about  each 
file  (i.e.,  the  directory  infor- 
mation). The  next  step  is  to 
initialize  a  number  of  the 
variables  which  well  use  to 
minimize  the  number  of  tape 
operations  required.  Also, 
there  Is  a  variable  which 
you'll  have  to  tailor  to  your 
own  system:  Rl,  which  tells 
how  many  records  can  fit  in 
memory  at  once. 

The  next  thing  the  pro- 
gram does  is  determine  how 
to  initialize  the  directory 
information.  If  this  is  the  first 
use  of  the  system  ever,  there 
is  no  directory  tape  yet,  so 
the  program  fills  zeros  into 
the  appropriate  parts  of  the 
directory,  and  gets  ready  to 
start  creating  the  first  file 
(which  will  eventually  be 
stored  on  cassette  tape  num- 
ber 1).  If,  on  the  other  hand, 


the  system  has  been  used 
before,  there  will  be  a  tape 
with  the  directory  informa- 
tion on  it,  and  the  program 
requests  the  user  to  mount  it 
and  read  it  in. 

Next,  the  program  offers 
to  print  a  summary  of  the 
available  commands  (that's 
handled  by  the  subroutine 
which  starts  at  statement 
3000,  which  we'll  get  to 
soon). 

Finally,  the  program 
enters  the  main  loop  (starting 
at  statement  2000)  which 
asks  for  a  COMMAND,  inter- 
prets it,  and  carries  it  out. 
The  program  segment  for  the 
END  command  begins  at 
statement  2040,  the  code  for 
the  LIST  command  begins  at 
2200,  the  ADD  at  2450,  and 
the  DELETE  at  2570.  If  the 
user  types  in  an  invalid  com- 
mand, control  passes  to  slate- 


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Action  Taken 

End  of  run.  If  the  file  currently  in  memory  has  b*ien  altered  in  any  way, 
write  it  out  to  its  cassette  tape.  If  the  directory  has  been  altered,  write  it 
out  also. 

Insert  a  new  record.  Ask  for  the  new  member's  name,  figure  out  what  file 
it  goes  on.  If  that  file  isn't  in  memory,  get  it.  Get  the  rest  of  the  member 
information  and  insert  the  new  record  in  alphabetical  order. 

Remove  a  record  from  the  library,  For  safety's  sake,  print  the  whole  record 
and  ask  again  before  deleting  it. 

Generate  3  mailing  list.  Go  through  the  entire  library r  starting  with  tape  file 
1,  printing  names  and  addresses  of  appropriate  members. 


Fig.  2  Basic  structure  of  the  record-keeping  program  with  each  command  described. 


93 


lA 


ment  2750. 

The  statements  which 
handle  the  commands  make 
frequent  use  of  subroutines 
to  carry  out  the  details.  As 
you  go  over  the  statements, 
keep  referring  to  the  flow 
chart  in  Fig.  2  to  see  how 
things  fit  into  the  overall 
scheme.  Incidentally,  even  if 
you  have  no  plans  whatsoever 
to  implement  this  program  on 
your  own  machine,  you'll 
learn  a  lot  by  making  sure 
you  see  how  the  program 
works,  and  by  trying  to  redo 
parts  of  it  in  different  ways, 
seeing  if  you  can  make  it 
cleaner  and  more  useful.  (I'm 
happy  with  it  the  way  it  is, 
but  everyone's  taste  and 
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The     Command     Summary 
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The  subroutine  which 
begins  at  statement  3000 
simply  prints  a  summary  of 
the  available  commands. 
Depending  on  your  taste,  it 
could  be  made  more  exten- 
sive, and  include  such  details 
as  how  to  load  and  start  your 
cassette  tape  equipment,  how 
to  store  the  tape  files,  and  so 
on,  On  the  other  hand,  if 
your  system  will  be  used  only 
by  people  who  are  very 
familiar  with  it,  the  sub- 
routine  could    be  shortened. 


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One  difference  from  last 
month's  scheme  is  that 
there's  no  longer  an  UPDATE 
command  for  altering  a  mem- 
ber's record.  Since  we're  now 
keeping  the  records  in  alpha* 
betical  order,  the  UPDATE 
command  isn't  as  simple  as 
before  —  if  the  spelling  of  the 
member  name  changes,  the 
program     would     have     to 


There  are  two  assumptions  that  heavily  influence  the  design  of  the  record -keeping  program.  First, 
I've  assumed  that  (eventually)  there  will  be  many  more  records  than  will  fit  in  memory  at  once.  If  in 
your  particular  application  that's  not  true,  you  can  simplify  the  program  substantially  (you  no  longer 
need  the  directory,  the  update  procedure,  nor  any  of  the  elaborate  tape  requesting  and  dumping 
machinations). 

The  second  assumption  is  that  we  have  only  one  simple,  slow  cassette  recorder  to  work  with.  That 
means  that  any  extra  work  the  program  can  do  to  avoid  reading  or  writing  tapes  will  be  well  worth  the 
effort.  By  keeping  the  records  in  alphabetical  order  and  by  keeping  a  directory  showing  where  each 
tape  file  starts,  we  can  figure  out  what  tape  file  a  particular  name  goes  on  immediately,  with  no  extra 
tape  reads.  By  keeping  track  of  whether  or  not  a  file  in  memory  has  been  altered,  we  can  avoid  any 
unnecessary  tape  write  operations. 

CHHECTOftY 

,- TOTAL    PJUMKfl  Or  NEC 0*0* 


3Q  246 


Of  M  PiWtT 
ACCORD  OH 
1*T*C    FiLE 


mjWflt*  OF   HIES 


1 

qu&l&.josT; 

5i 

2 

FONTAiN£,SAHuEL 

70 

a 

LAMBERT, JOHN  M 

64 

4 

TAruofi,  ROSE  S 

<2> 

■TMint  ARE  *■ 
RECORDS  OH  t\L%  4 


The  directory  at  a  particular  point  rn  time. 


Other  Key  Variables: 


Dl 


T1 


R1 


=  1  if  directory  has  been  altered 

at  any  time  during  the  current  run. 

=  1  if  the  tape  file  in  memory 
has  been  altered  in  any  way. 

=  the  maximum  number  of  records  per  file. 


94 


k 


remove  the  old  record  and 
insert  the  changed  version  of 
it  in  the  proper  place.  It 
seemed  simpler  to  me  to  just 
provide  a  DELETE  command 
and  let  the  user  do  updates 
with  it.  Again,  it's  a  matter  of 
taste.  If  you  feel  that  you'd 
rather  have  an  UPDATE  com- 
mand, or  you'd  like  to  add 
some  other  command,  the 
way  the  main  program  is 
organized  makes  it  easy  to  do 
so.  For  example,  suppose  you 
want  to  add  a  command 
called  PRINT  which  asks  for 
a  member's  name  and  then 
prints  the  corresponding 
record.  All  you'd  have  to  do 
is  insert  an  appropriate  test  at 
statement  2750,  insert  the 
appropriate  statements  at 
that  point,  and  shift  the  state- 
ments which  handle  illegal 
commands  down  to  the  end, 
like  this: 


una'  mil  &e*  mi 


wm *■•:.'. 


Nfft 
HMD 


asus 

cxjoam  top 
CO  to  moo 


ca~  mr« 


The    Get    Name,    File,    and 
Location  Subroutine 

This  subroutine  performs  a 
fairly  simple  task  concep- 
tually —  namely,  getting  a 
member's  name  from  the  user 
and  then  finding  where  it 
goes.  However,  since  the  right 
file  may  not  be  in  memory,  it 
can  take  a  fair  amount  of 
thrashing  around  to  accom- 
plish this  task. 

Getting  the  member's 
name  is  easy,  but  how  do  we 
use  the  directory  to  discover 
which  file  that  member's 
record  should  be  on?  The 
F$(  )  part  of  the  directory 
gives  the  first  member  on 
each  file.  We  begin  by  con- 
sidering file  number  1  (the 
variable  T2  stores  the  number 
of  the  tape  file  we're  con- 
sidering). If  there  is  only  one 
tape  file,  then  we're  done  — 
the  member  must  go  on  file 
1 .  If  there  are  more,  we  get  to 
line  4080,  If  the  name  we 
seek  comes  before  the  first 
name  on  file  2,  we*re  done  — 
again,  the  member  must  go 
on  file  1,  If  on  the  other 
hand,     the    name    we    seek 


comes  after  the  first  name  on 
file  2,  the  test  in  line  4080 
fails,  and  we  add  one  to  T2 
and  go  through  the  process 
again.  Eventually,  either  we 
come  to  the  last  tape  file  (and 
the  test  in  line  4070 
succeeds),  or  else  we  find  that 
the  name  goes  before  the  first 
name  on  file  T2+1  (and  the 
test  in  line  4080  succeeds).  In 
either  case,  when  we  exit  to 
line  4110,  we  know  that  the 
member  belongs  on  file  T2. 
Next,  the  routine  checks 
to  see  if  the  right  file  is 
already  in  memory  (line 
4120),  and  if  not,  we  flush 
out  whatever  file  Is  in 
memory  (using  the  flush  sub- 
routine which  begins  at  state- 
ment 7000)  and  request  the 
proper  file  (using  the  tape 
read  subroutine  —  line  6000). 
At  last  we  have  the  right  file 
in  memory  and  we  can  call 
the  search  subroutine  (line 
5000)  to  determine  where  the 
record  goes  in  the  file. 


fflFKT     V2U*Eh   I^AIX   Si«t    ffltlT  h  MIP'JL  I   *HtfTl»fc- 
"FM      WHAT  V»t   nrufl    'PI'   Fit    - 

ir  t:  •  ■    "im  #un 

if  r;  :<ri4  4UD 

in  " 

T|?   *JM 

»(w     ■***  OKtC  Mow* 


•  r 


■hr., 
■1.  ►. , 

*0K 


u-*  - 


IB.      -*■ 


Binary  Search  Subroutine 

The  next  subroutine  is  a 
key  one.  It's  the  subroutine 
that  searches  the  records  in 
memory  for  a  particular 
member's  name  {stored  in 
P$),  It's  different  from  last 
lime  because  now  we're 
storing  the  records  in  alpha- 
betical order  of  the  members' 
names.  The  main  reason  we're 
doing  that  is  to  minimize  the 
number  of  tape  operations 
the  user  has  to  do.  However, 
there's  an  added  benefit.  Our 
program  will  be  able  to  look 
up  records  much  faster  than 
before.  Why's  that? 

Imagine  how  horrible  it 
would  be  if  the  phone  com- 
pany listed  people  in  their 
phone  directory  in  the  order 
in  which  they  signed  up  for 
phones!  My  phone  book  has 
about  72,000  listings  in  the 
white  pages.  Even  if  I  could 
look  at  5  entries  per  second, 


it  would  take  two  hours  to 
find  a  number,  on  the 
average,    (That's   assuming    I 

didn't  go  bananas  first,)  Of 
course,  the  phone  company 
has  had  the  good  sense  to  put 
the  listings  in  alphabetical 
order,  and  we  all  know  how 
to  use  that  fact  to  enable  us 
to  find  a  number  in  a  few 
seconds.   Quite   a  difference. 

It's  easy  to  see  why  having 
the  entries  in  alphabetical 
order  is  such  a  big  deal.  If 
they're  not,  when  I  look  at  an 
entry  and  it  turns  out  not  to 
be  the  right  one,  I've  elim- 
inated just  that  one  possi- 
bility, On  the  other  hand,  if 
they  are  in  order,  and  I  look 
at  an  entry  near  the  middle  of 
the  phone  book,  if  it's  not 
the  right  one,  I  can  eliminate 
36,000  entries  from  further 
consideration  by  checking 
whether  the  name  I  want 
comes  before  or  after  the  one 
I  just  looked  at. 

It's  all  very  well  to  imagine 
looking  up  numbers  in  the 
phone  book  —  now  we  have 
to  devise  a  computer  program 
that  mimics  what  we  do.  The 
key  idea  seems  to  be  that  as 
we  go  along,  we  keep  nar- 
rowing down  the  region  of 
the  phone  book  in  which  the 
entry  must  lie.  Let's  use  two 
variables,  one  called  L  (for 
Low)  which  stores  an  array 
subscript  value  which  we 
know  to  be  lower  than  the 
position  of  the  name  we  seek, 
and  one  called  H  (for  High) 
that  stores  a  value  which  is 
higher  than  the  subscript  of 
the  desired  element.  Then, 
each  time  through  the  loop, 
we'll  look  at  the  array 
position  midway  between  L 
and  H.  If  it's  the  name  we  Ye 
looking  for,  we're  done.  If 
the  name  comes  earlier  than 
the  one  we  just  looked  at, 
we'll  adjust  H,  If  it  comes 
later,  we  adjust  L.  If  Land  H 
squeeze  together  before  we've 
found  the  name  we  want, 
that  means  that  the  name 
wasn't  in  the  array  at  all,  but 
that  it  should  be  at  location 
H.  Since  each  step  of  this 
procedure  can  eliminate  half 
of  the  remaining  possibilities, 
it's  called  a  binary  search 
procedure.     Follow    through 


_TZ 


LOW* 1 

HIGH-* —  no 
OF  EHTRI6S 


iO«*—  GUT  55 


I 


I  til  *     GuClt 


T 


Fig.  3,  The  binary  search  procedure. 


the  flow  chart  in  Fig.  3  with  a 
few  examples  to  get  a  feeling 
for  how  it  works. 


HEW 

BINAHV   IMMLff   RftL/TINE 

♦mil- 

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•  i  u 

MUM 

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'. 

HEM 

IN   Ml  Mi  IH  •    KIN   FILE      1    i 

MMo 

HE3 

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1-iM' 

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POSIT  KM 

W 

ma 

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Hn 

BjlUPMIi       *  H     %C7    *C"L**L     lltlM 

MHO 

r^i  it 

fOlMQ  AT  »Ollfi:  - 

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■    _ 

■      t.**  Mat 

M» 

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tv* 

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■  ltd 

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■      '■! 

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fltTURW 

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Utt 

P- 

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:pQ 

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HtltM 

the   input,   it  assumes  that's 

the  end  of  the  value,  so  that, 
for  example,  the  comma  after 
the  member's  last  name 
divides  the  entire  member's 
name  into  two  separate 
strings. 


t-mi 
en  ii 
6i?:i 
Eii  no 

CI  411 
tilbL/ 

nil 


«MMJI  *m  K14A  IJN 

mtt     v*  -  l#  t*/i;  m  »  j*<  ■  *  rtckfc 

m»  0  "-« 

*i 

**!M  ULtlJI 

'ii',""ni 

I  HI"!  1 1    H.tl 

I  I   l>tui   :<J=       -si 
INMllf   Til  1 1  \n»- 

'   i 

mtt  aauME  mmRaunw  n 


Read  Tape  Subroutine 

This  subroutine  is  fairly 
simple,  but  parts  of  it  depend 
on  the  details  of  your  cassette 
tape  interface.  Tve  assumed 
that  on  your  system,  you  can 
'Tool"  the  BASIC  interpreter 
into  accepting  input  values 
from  tape  through  INPUT 
statements.  On  our  system, 
we  dig  into  the  interpreter 
code  and  change  the  I/O  port 
specification  used  by  the 
routine  that  handles  terminal 
I/O-  After  the  desired  values 
have  been  read  in  from  the 
tape,  we  switch  it  back  so 
that  further  INPUTs  come 
from  the  terminal, 

The  sequence  of  state- 
ments from  6080  to  6140 
may  look  a  little  weird  unless 
you  recall  that  every  time 
BASIC  comes  to  a  comma  in 


■ 

tiO  ton 


HT    - 


KM 


Flush    Current    File   Subrou- 
tine 

If  the  file  that's  currently 
in  memory  hasn't  been 
changed  in  any  way,  Tl  will 
equal  0,  and  we  get  away 
with  doing  nothing  (and  the 
user  can  just  rewind  the  tape 
and  put  it  away  without 
waiting  for  the  file  to  be 
rewritten).  If  it  has  been 
altered,  we  copy  the  new 
version  back  to  cassette  tape 
for  storage  using  the  tape 
write  subroutine,  "52"  is  a 
parameter  which  tells  the 
tape  write  subroutine  where 
to  start  from  in  memory.  In 
the  "flush"  operation,  we 
want  to  write  the  entire  file, 
so  we  set  S2=0. 


95 


U 


I l_l_lli  Hjplij  I'  Tar 

*i  H.L*    HTH4& 

mtunn 


Tape  Write  Subroutine 

Like  the  tape  read  subrou- 
tine, this  one  is  simple  con- 
ceptually, but  depends  on 
your  ability  to  write  a 
machine  language  program  to 
"foot"  the  BASIC  interpreter. 
In  this  case,  we  want  to  make 
the  output  from  a  PRINT 
statement  go  to  the  tape 
machine  instead  of  the 
terminal.  If  that's  hopelessly 
messy  on  your  system,  you 
may  wind  up  having  to  write 
a  machine  language  routine  to 
handle  all  the  details  of 
memory-to-tape  operations. 
Maybe  someday  there'll  be 
standards  adopted  and 
accepted  so  we  don't  have  to 
keep  "reinventing  the  wheel11 
everytime  we  want  to  do  I/O! 


t«    4RM      T4I-C  ,W  n   fttfA&H' 


*!  JO         41 

JlJO    **M     »ii  *M=HHil  i,**6*j*ui   lUiHOMTW 

RlflU     Ml   |l 


Insert  New  Record  Subrou- 
tine 

This  subroutine  is  used  to 
carry  out  the  ADD  command. 
It,  like  the  search  routine,  is 
more  complex  than  last  time 
because  we  now  want  the 
records  to  be  in  alphabetical 
order.  If  you  look  back  at  the 
main  program,  you'll  see  that 
this  subroutine  is  called  after 
we're  sure  the  right  tape  file 
is  in  memory,  and  after  we've 
determined  where  the  new 
record  should  go  in  that  file 
(the  binary  search  routine 
returns  the  location  in 
memory  cell  "l").  In  order  to 
keep  the  records  in  order,  we 
have  to  shift  some  of  the 
records  already  in  the  file  to 
make  room  for  the  new 
entry. 

The  old  adage  "you  don't 
get  something  for  nothing" 
applies  here.  Although 
keeping  the  records  in  order 
lets  us  look  things  up  faster, 
it  makes  inserting  a  new 
record  slower.  With  last 
month's     scheme,     we     just 


Debugging:  Some  Tips 

The  first  principle  of  debugging  may  seem  obvious,  but  for  some  reason  it  gets  violated  all  the  time. 
You  ha\m  to  know  what's  supposed  to  be  going  on  before  you  can  teff  what's  wrong.  In  practical 
terms,  that  means  that  you  should  have  your  flow  charts,  plans,  and  notes  by  your  side  (and  you 
should  use  them)  as  you  try  to  figure  out  why  the  program's  responses  are  wacky,  why  you're  getting 
thai  error  message,  why  you  feel  nervous, 

BASIC  provides  some  nice  features  that  aid  debugging.  It's  easy  to  toss  STOP  statements  at  suspect 
places,  and  when  the  program  stops  there,  to  use  the  system  in  the  "console  mode"  to  investigate 
what's  happening. 

For  example,  when  I  ran  into  trouble  with  the  shift  routine,  I  typed 
11125  STOP 

and  ran  the  program  again,  When  it  stopped  at  1 11 25,  I  typed 
PRINT  SO,  FO 

and  the  system  responded 
■1  0 

That  told  me  why  (  was  getting  the  "subscript  out  of  range"  error  message,  but  why  was  SO 
starting  off  at  -1? 

The  important  thing  at  this  point,  and  the  thing  that  takes  some  discipline,  is  to  resist  the 
temptation  to  slap  in  the  first  fix  you  can  think  of  that  will  cure  the  immediate  symptom.  You'll  be 
much  better  off  if  you  take  your  time,  prowl  around  checking  values,  figuring  out  what  the  real 
problem  is.  In  this  case,  it  turned  out  that  my  whale  strategy  for  shifting  was  wrong.  If  1  had  fust 
changed  the  statement  that  set  SO  to  its  initial  value,  the  program  would  have  failed  in  other 
situations. 


stuck  the  new  records  in  the 
next  unused  location  in  the 
arrays.  Now  we  have  to  move 
records  (half  of  them  on  the 
average)  to  make  room  for 
the  new  record.  The  time 
difference  will  be  barely 
noticeable  compared  to  the 
tremendous  savings  we  make 
by  eliminating  tape  read  oper- 
ations, so  we're  still  miles 
ahead  with  our  new  scheme. 

After  adding  a  new  record, 
we  need  to  change  the  direc- 
tory and,  since  we've  just 
altered  the  die,  we  have  to 
make  sure  that  Tl  Is  1  to 
reflect  that  fact  (see  lines 
9200  through  9230). 

Before  we  RETURN, 
there's  one  more  thing  we 
have  to  check.  What  if  adding 
this  record  has  completely 
filled  memory?  If  so,  the  next 
ADD  command  would  cause 
the  file  to  overflow.  Since  Rl 
tells  how  many  records  are 
allowed  on  a  filet  we  see  if 
we've  hit  the  limit  in  line 
9260,  Remember  that  G(T) 
tells  how  many  records  are  on 
file  T  If  we  have,  we  initiate 
an  update  operation  by 
calling  the  update  subroutine. 


NrtVitHEII 


roa  Hi*      -i  i    ■ 

■WJU    MIM 

nam    i  r  > 

WVK    riciLi*  1  I  BCC 

HH   *t¥     QET  mt 


_  ■*■  _ 


Tt» 


■ 


Delete   A  Record  Subroutine 

This  subroutine  carries  out 
the  details  of  the  DELETE 
command.  It  uses  the  shift 
subroutine  to  shift  all  records 
after  the  one  to  be  deleted, 
updates  the  directory,  and 
notes  (by  making  sure  that 
Tl  is  1 )  that  the  file  has  been 
altered* 


PI  LI  N    '"■"    "D  -   '  "'  • 

■     L'liF  v*\  f  t  sue  i  •'  ■   ■ '  ■ 

MM 


LCI 


Shift  Subroutine 

This  routine  does  the  shift- 
ing required  by  the  insert  and 
delete  subroutines.  For  some 
reason,  it  was  a  real  pain  in 
the  neck  to  write.  It  seems 
like  such  a  simple  thing  to  do, 
and  now  that  I've  got  it  work- 
ing, it  looks  so  reasonable, 
but  .  , .  I  wrote  it  slightly 
differently  at  first,  only  to 
find  that  it  blew  up  the  first 
time  1  did  an  ADD,  The 
problem  was  that  G(T)  is  0 
before  file  T  has  any  records 
on  it,  and  the  way  I  had 
written  the  stupid  thing,  it 
tried  to  access  array  location 
-1-  Tm  sure  it  demonstrates 
some  Grand  Principle  about 
programming,  but  which  one 
I  don't  know.  Probably  some 
variant  of  Murphy 's  Law. 


hum  ■ 


D'l 


TO  I  r  rl  tl 
r'«w    np-v     O" 
tttM      kt '   =*' 
MHO       L 


MIS 

If  JO* 

una 


iet  etna  ■*< 

LET  t-3'Mi-lltlBUCl 

t,Et  www  imfroi 

PMULMSDI 
ktT  B-BC 


Update  Subroutine 

When  repeated  ADDs  have 
filled  up  a  file,  we  have  to  do 
something  about  it.  The  most 
reasonable  thing  to  do  seems 
to  split  that  file  in  half  and 
make  two  tape  files  out  of  it. 
Why  does  that  seem  reason- 
able? Another  option  would 
be  to  add  a  new  tape  file  at 
the  end  of  the  library,  and 
then  spread  the  records  from 
all  the  files  out  evenly.  Since 
that  would  mean  a  tremen- 
dous number  of  tape  reads 
and  writes  if  the  library  was 
big,  I  ruled  it  out  (we  don't 
want  people  sitting  around 
muttering  subversive  things 
like  "Why  don't  we  up  the 
club  dues  and  get  a  disk?"). 
After  I  had  ruled  out  the 
second  option,  1  came  up 
with  another  reason  for  ruling 
it  out:  If  a  particular  file  has 
overflowed,  it  might  be 
because  a  lot  of  club  mem- 
bers have  names  in  the  same 
part  of  the  alphabet,  so  it 
makes  more  sense  to  make 
more  room  right  around  that 
I  ite  than  to  make  a  little  more 
room  throughout  the 
alphabet. 

Since  the  update  yields 
two  tape  files  where  there 
was  one  before,  and  since  the 
tape  files  themselves  have  to 
be  kept  in  alphabetical  order 
for  the  directory  scheme  to 
work  right,   the  user  has  to 


A 


96 


Some  Possible  Improvements 

One  added  feature  that  would  be  worthwhile  would  be  for  the  LIST  command  to  convert  the 
member  names  to  the  "first  middle  last"  form  before  printing  out  Che  mailing  labels.  Most  people 
would  probably  rather  have  their  mail  addressed  to  them  that  way.  Your  version  of  BASIC  should 
have  built-in  string  manipulation  functions  which  will  make  it  easy  to  code  this  flow  chart: 


C.t44H—  CHfl* 
*  I 


PfllNT  EVERYTHING    AFTER 
THE    CHAft-TH     CHARACTER, 
THEN   A   BLANK, THEN   EVERYTHING 
BEFDUE   THE    CHAR-THi   CHARACTER 


I 


Another  problem  that  could  use  some  work  is  that  the  program  is  totally  unforgiving  about 
misspellings.  You  might  find  it  nicer  to  have  the  program  check  just  the  first  letter  of  the  commands, 
so  that  misspellings  like  the  one  in  the  sample  run  (DELTE  for  DELETE)  wouldn't  make  any 
difference.  A  similar  but  bigger  problem  is  that  if  you  don't  abbreviate  a  member's  name  the  same  way 
on  different  occasions,  the  program  will  treat  each  different  spelling  as  a  different  member.  One 
solution  would  be  to  write  a  subroutine  which  can  tell  if  two  names  are  "close."  It  could  decide  that 
two  names  were  "close"  if  the  last  names  were  the  same  and  the  first  names  have  a  lot  of  letters  in 
common.  Then  if  the  user  types  a  name  that  the  program  can't  find,  the  program  can  look  for  names 
that  are  "close"  to  the  one  the  user  wants.  If  the  program  manages  to  find  such  a  name,  it  should  then 
ask  the  user  if  the  two  names  actually  refer  to  the  same  person. 

One  fast  thing:  If  you're  tight  on  memory,  you'll  probabty  benefit  by  redoing  the  part  of  the 
program  that  decides  when  to  do  an  update.  If  you  have  the  program  count  the  number  of  characters 
on  each  file  instead  of  just  the  number  of  records,  you'll  be  able  to  squeeze  every  last  byte  out  of  your 
memory.  Hopefully  your  version  of  BASIC  has  a  built-in  function  that  computes  the  length  of  a  string 
(it's  called  LEN  in  Altatr  BASIC),  which  will  help  greatly. 


renumber  all  the  tapes  after 
the  one  being  updated.  That's 
a  possible  source  of  error,  so 
anyone  who  is  going  to  have 
access  to  the  system  should 
be  warned  about  it.  If  the 
tape  files  do  happen  to  gel 
out  of  order,  the  tape  read 
subroutine  will  catch  the 
error  (see  lines  6190  through 
6220),  but  it  might  take  a 
number  of  laborious  tape 
reads  to  get  things  working 
again. 

The  subroutine  should  be 
pretty  easy  to  follow.  It 
copies  the  second  half  of  the 
file  in  memory  to  the  new 
tape  and  then  updates  the 
directory  appropriately.  It 
leaves  the  rest  of  the  old  file 
in  memory,  and  since  it's  still 
file  number  Tp  nothing  has  to 
be  done  except  to  record  its 
new  (shorter)  length  in  the 
directory  (line  12240). 


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Using  The  System 

To  use  the  record-keeping 
program  on  your  system,  you 
need  to  copy  the  statements 
in    the    program,   fill   in   the 

calls  to  machine  language  sub- 
routines to  do  the  cassette 
tape  operations,  find  a  good, 
safe  place  to  store  the 
cassette  tapes  which  hold  the 
directory  and  files,  and  let  'er 
rip!  Here's  a  sample  run 
showing  some  of  the  features 
(I've  underlined  the  parts  I 
entered). 


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The  only  things  that  aren't 
demonstrated  in  the  sample 
run  are  the  mailing  LIST 
option,  which  prints  names 
and  addresses  (we  cut  them 
out    of    the    listing   and   use 


them  as  address  labels),  and 
the  update  operation,  which 
happens  whenever  a  file  gets 
full 

So  that's  the  record- 
keeping program.  In  one 
sense,  it's  finished  -  it  works, 
it  does  what  I  wanted  it  to, 
it's  useful.  In  another  sense, 
it'll  never  be  finished  —  as  it 
gets  used,  inconvenient 
features  come  to  light;  occa- 
sionally other  ways  to 
organize  it  enter  my  mind.  I 
guess  the  ultimate  record- 
keeping program  would  be 
one  that  did  absolutely  every- 
thing all  by  itself,  from  read- 
ing the  morning  mail,  to 
cashing  checks,  to  sending 
notices  to  people  who  are 
behind  in  their  dues,  to 
keeping  me  company  when 
nobody  is  around.  That  one 
will  have  to  wait  a  while. 

As  The  Smoke  Clears  . .  . 

Well.  We've  covered  an 
incredible  amount  of  material 
in  these  three  articles. 
Possibly  too  much,  Certainly 
too  much  to  absorb  com- 
pletely if  you  really  were 
starting  from  scratch  in  Part 
L  But  even  if  it  doesn't  all  fit 
together  for  you  yet,  I  hope 
the  feeling  of  what  it's  like  to 
program  got  across.  The 
feeling  that  when  you 
actually  start  doing  some- 
thing, you're  in  for  a  struggle 
at  times,  some  ups  and 
downs.  The  feeling  that  to 
create  a  finished  product  you 
have  to  keep  refining,  testing, 
and  revising  your  plans.  No 
one  has  ever  written  even  a 
medium-sized  program  by 
just  sitting  down  at  the 
terminal  and  pounding  out 
lines  of  BASIC.  If  that  was  all 
there  was  to  it,  it  wouldn't 
even  be  much  fun.  What  I 
really  like  about  program- 
ming is  that  it  involves  many 
apsects  of  life  itself:  dream* 
Ing,  planning,  testing, 
bringing  your  dreams  down 
to  the  hard  reality  of  what 
the  machine  can  do,  getting 
the  bugs  out,  refining  your 
plans,  finally  seeing  your  pro- 
gram run,  using  it,  and  then 
starting  to  dream  about  the 
next  grand  scheme*  It's 
great!  ■ 

97  Jn 


/ft**  ChJdstmas 

1/tJDnt 


35: 

lUaue.  TTlate. 


&  all  our  dealers 


Where  you  can  get 
the  Jupiter  II  computer 
system- a  computer 
for  all  reasons! 


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Now  were  on  TV! 


Wave  Mate  introduces  Jupiter  IIC, 

a  complete  computer  system 

incorporating  a  monitor  quality 

TV  interface.  This  svstem 

provides  everything  you  need 

to  create  and  run  application 

programs.  Jupiter  IIC  includes 

a  CPU  witli  8K  dynamic  RAM 

and  3K  ROM  memory;  video 

terminal  interface  and 

keyboard,  and  dual  audio 

cassette  tape  interface. 

The  TV  interface  features 

upper  and  lower  case  and 

Greek  character  sets,  and  dot  graphics.  The  dual  audio  cassette  interface 

provides  start/stop  operation  and  operates  at  300,  600?  or  1  200  baud. 

And  of  course  we  still  provide  these  high-quality  features:   burn-in 

tested  ICs,  socketed  IC's,  complete  documentation,  and  more. 


THE  COMPLETE  COMPUTER 
INCLUDING  PERIPHERALS 


■■csrsiijiiJMCUiiiB  i 

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ATTENTION: 
ORIGINAL  EQUIPMENT 
MANUFACTURERS 

Jupiter  IIC  provides  OEMs 
with  the  tools  to  get  systems 
into  the  field  faster  and  at 
lower  cost.  (1)  Use  Jupiter  IIC 
as  your  development  system. 
Perfect  for  development  of 
software  and  special  hardware. 
(2)  Use  Jupiter  IIC  for 
prototype  systems.  Only 
Wave  Mate  provides  the  tools  - 
wire  wrap  modules,  universal 
modules,  complete 
documentation  —  to  easily 
tailor  system  logic  and  add 
customized  interfaces  within 
the  basic  Jupiter  IIC  package. 


SOFTWARE 

All  Jupiter  IIC  systems  feature  a  sophisticated  monitor/debugger  package  including  a  versatile 
interrupt  system  and  I/O  monitor  call  instructions.  A  programmable  macro  editor  and  expanded 
assembler  are  also  provided.  Proposed  ANSI  standard  BASIC  is  included  with  Jupiter  IIC, 

THE  JUPITER  IIC  KIT:  $2850 

The  kit  includes  the  CPU,  software  debugger  and  monitor  module,  8K  dynamic  memory,  module 
cage,  power  supply,  front  panel,  video  interface^  cassette  interface,  and  all  the  documentation 
required  to  assemble,  run,  and  understand  the  system  as  well  as  modification  instructions  for  a 
black  and  white  TV  set* 

THE  JUPITER  IIC  ASSEMBLED  SYSTEM:  S3800 

All  components  of  the  Jupiter  IIC  kit  plus  two  audio  cassette  units  and  a  12~inch  black  and 
white  TV  set.  The  complete  system  is  shipped  with  all  components  assembled  and  tested* 


SPECIFICATIONS 
CPU 

MC  6800;  eight-level  interrupt, 
prioritized  and  maskable  by 
level;  single-cycle  and  block 
DMA 


DUAL  AUDIO  CASSETTE 

Complete  paper  tape  replace- 
ment; start/stop  motor  con* 
trot;  300,  600,  or  1200  baud 
{crystal  controfled);  error 
correction 


VIDEO  TERMINAL 
INTERFACE 

64  x  32  lines 

Upper  and  lower  case, 

plus  Greek  alphabet;  7x12  format, 

128  dot  (hor.)  x  96  dot  (vert.) 

graphics 


MEMORY 

8K  dynamic  RAM;  3K  ROM; 
IK  dual-port  static  RAM 

KEYBOARD 

Generates  fufl  1 28-character 
ASCII  set 


□  Send  details  on  Jupiter  II  systems 

□  Have  salesman  call 

Name   


P    TitJe    

I    Company 
I    Address  - 

I    City  

Phone  


~  State 


Zip 


SE 


UUmj.  Tfimta. 


WAVE  MATE  1015  West  190th  Street,  Gardena,  California  9D248 

Dept.  203 


Telephone  (213)  329-8941 


99 


2 


Dan  StogdUl  VE5DWC 
IB2  Victoria  Street 
Si.  Marys,  Ontario 
CANADA  NQM  2VQ 


Getting  By  the  Friden -8800 

Communications  Gap 


-  -  interface  made  easy 


Recently,  a  number  of 
Friden  keyboard* 
printers  and  associated  con- 
trollers have  appeared  on  the 
surplus  market.  This  article  is 
concerned  with  the  TM 
20K714  keyboard-printer  and 
its  companion  TM  20K715 
controller,  which,  in  combin- 
ation, formed  the  heart  of  the 


Burroughs  9350-2  Communi- 
cations Terminal.  While  these 
are  certainly  impressive 
looking  units,  hobbyists  have 
been  experiencing  difficulty 
in  getting  them  "on-line'* 
with  their  home  computer 
systems*  This  article  describes 
the  hardware  modifications 
and  the  software  which  were 

Photo  by  Doug  Wood 


implemented  to  overcome  the 
communications  gap  which 
existed  between  my  8800  and 
the  asocial  Friden. 

Hardware 

Hardware  modifications  to 
the  8800  and  the  Friden's 
control  unit  are  relatively 
straightforward. 


The  Allairj Friden  system.  The  8800  is  sitting  next  to  the  Friden  TM  20K714  keyboard-printer. 
The  TM  20K71 5  controller  (without  its  cover)  is  visible  under  the  table. 


The  input  and  output  of 
the    controller    is    RS-232-B 

compatible.  In  this  configura- 
tion, the  resting,  mark,  or 
logic  1  condition  is  more 
positive  than  +3  vojts  and  the 
space  or  logic  0  condition  is 
more  negative  than  -3  volts. 
The  El  A  serial  interfaces, 
which  are  being  used  by  most 
hobbyists,  conform  to  RS- 
232-C  specs.  This  configura- 
tion defines  the  logic  1  condi- 
tion as  more  negative  than  -3 
volts  and  the  logic  0  con- 
dition as  more  positive  than 
+3  volts.  Consequently,  for 
150  baud  serial  transmission 
to  and  from  the  Friden  it  is 
necessary  to  invert  the 
polarity  of  the  transmitted 
and  received  data  signals. 

Due  to  the  fact  that  I  have 
a  Processor  Technology  3P+S 
interface,  the  parts  necessary 
to  invert  the  signals  already 
existed  on  the  board  (see  Fig. 
1).  Pin  25  (the  "Tx  Out"  of 
the  UART)  was  connected  as 
usual  to  the  appropriate  gate 
of  1C5,  which  provides  the 
RS-232-C  output.  The  output 
of  this  gate  was  connected 
back  to  the  input  of  a  second 
gate  of  IC5,  The  output  of 
this  second  gate  now  pro- 
vided the  appropriate  polarity 
signal  for  transmission  to  the 
terminal,  Le.,  the  output 
signal  now  conformed  to 
RS-232-B  specs  as  a  result  of 


A 


100 


the  additional  inversion  pro- 
vided by  the  second  gate.  In 
order  to  receive  data  from  the 
Friden,  two  gates  of  IC10  on 
the  3P+S  were  similarly  cas- 
caded. The  additional  inver- 
sion provided  by  the  first  gate 
makes  the  Fr idea's  RS-232-B 
transmitted  signal  appear  as 
RS-232-C  to  the  second  gate. 
The  output  of  this  second 
gate  is  connected  to  pin  20, 
the  "Rev  In"  of  the  UART. 

For  those  of  you  who  have 
other  I/O  interfaces,  all  that 
is  required  is  to  connect  an 
inverter  (such  as  a  TTL  NOR 
gate)  between  the  data  pins 
of  the  UART  and  whatever 
circuitry  (be  it  transistor  or 
IC)  which  presently  boosts 
the  I/O  signals  to  the 
R5-232-C  level.  By  inserting 
the  inverters  between  the 
UART  and  the  existing  cir- 
cuitry, you  will  invert  the 
data  signals  and  still  maintain 
the  RS-232  drive  levels.  Such 
would  not  be  the  case  if  the 
TTL  inverters  were  external 
to  the  existing  circuitry. 

The  only  other  hardware 
modification  required  is  at 
the  25-pin  connector  of  the 
Friden's  controller.  Tie  pin  5 
(Clear  to  Send  Line)  to  pin 
20  (Terminal  Ready  Line). 
With  pin  5  positive  and  the 
ON-LINE  switch  activated, 
the  orange  ON-LINE  light 
will  be  illuminated,  con- 
firming the  status  of  the 
Friden.  The  Friden  is  now 
capable  of  transmitting  to, 
and  receiving  from,  the  8800. 

To  help  clarify  the  logic  of 
the  software  routines  which  I 

developed,  il  is  beneficial  to 
examine  the  terminal's  trans- 
mi  ssion  and  reception 
procedures. 

Keyboard  Transmission  Pro- 
cedure 

To  transmit  from  the  key- 
board, assuming  the  terminal 
is  operating  properly  "on- 
line," the  operator  presses  the 
TRANSMIT  key.  This 
initiates  the  transmit  mode, 
tights  the  TRANSMIT  and 
SEND  lamps,  unlocks  the 
keyboard,  and  causes  the 
transmission  of  an  STX  char- 


acter to  occur.  The  operator 
may  then  enter  a  block  of 
data,  terminating  it  by 
pressing  the  ETB  or  ETX  key. 
(Data  are  provided  to  the  line 
as  keyed,  and  also  stored  in 
the  terminal's  buffer  for 
possible  later  retransmission.) 
For  simplicity's  sake,  we  will 
not  make  use  of  this  retrans- 
mission feature.  Following 
transmission  of  the  ETB  or 
ETX  character,  the  SEND 
lamp  then  turns  off  and  the 
terminal  generates  a  Longi- 
tudinal Redundancy  Check 
(LRC)  character,  which  it 
also  sends  down  the  line  to 
the  computer.  The  terminal 
then  waits  for  an  ACK  status 
character  from  the  computer. 
If  this  is  received  when  the 
transmission  was  terminated 
by  an  ETB,  the  terminal  is 
cleared,  the  keyboard  un- 
locks, and  the  SEND  lamp 
comes  on.  The  last  block  of  a 
transmission  should  be 
terminated  by  an  ETX  char- 
acter. Now,  following  recep- 
tion of  an  ACK  character  by 
the  terminal,  the  TRANSMIT 
lamp  goes  out  and  the 
terminal  returns  to  the  idle 
mode. 

A  conventional  input 
routine  will  readily  accept 
data  from  the  Friden.  Since 
instances  of  these  are  com- 
mon,  I  will  not  get  into  a 
description  of  one  here.  How- 
ever, a  few  suggestions  con- 
cerning the  routine  are  in 
order.  You  may  choose  to 
have  the  routine  ignore  the 
STX  character,  since  it  is  not 
a  piece  of  valid  data  with 
reference  to  your  text.  How- 
ever, the  routine  should 
recognize  the  ETB/ETX  char- 
acters as  flags,  and  upon  their 
detection  send  an  ACK  to  the 
Friden.  Your  input  routine 
should  also  ignore  the 
terminal  generated  LRC  char- 
acter; like  i he  STX,  it  is  not 
relevant  to  the  actual  text 
being  transmitted.  You  could 
use  a  routine,  similar  to  the 
one  presented  later,  which 
will  use  the  LRC  for  detec- 
tion of  transmitted  errors, 
but  it  is  not  necessary  for  the 
input  routine.  (As  you  will 
soon  see,  the  LRC  character 
plays    a    major    role   in   oui- 


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BACK  P.4NL. 
21  PIN  CQMNECTCIR 


DATA  OUT 
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P3    25  PIN  PLUG 
fRO»*  THE 

TM  20  K  7>S 
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Fig.  L  The  Interconnection  between  the  Friden  *s  TM  20K7J5 

controller  and  the  Processor  Technology  3P+S  Interface.  Note 
the  cascading  of  the  top  two  gates  of  IC5  and  /ClQi  to  provide 
the  necessary  inversion. 


putting  data  to  the  Friden.) 
Note  that  it  is  important 
(necessary)  to  reply  to  trans- 
missions from  the  Friden  by 

sending  back  the  ACK  char- 
acter; otherwise,  the  key- 
board will  remain  locked  up 

and  the  TIME-OUT  and 
ERROR  lamps  will  come  on. 
Keep  in  mind  that  the 
Friden's  buffer  has  a  maxi- 
mum capacity  of  150  char- 
acters before  the  OVER- 
FLOW light  comes  on, 

Printer   Reception  Procedure 

When     the     terminal     is 

neither  transmitting  nor 
actively  receiving,  it  is  in  an 
idle  mode.  Message  reception 
begins  with  the  detection  of 
an  STX  character  from  the 
computer.  As  characters  are 
received,  they  are  placed  in 
the  Friden's  buffer.  Upon 
reception  of  an  ETB/ETX 
character,  the  terminal  gen- 
erates an  LRC  character  and 
looks  for  an  identical  LRC 
character  to  be  sent  down  by 
the  computer.  If  no  LRC 
errors  have  been  detected,  the 
terminal  transmits  an  ACK 
character  to  the  computer 
and  commences  to  print  the 
contents  of  its  (the 
terminal's)  buffer.  The 
terminal  resets  the  green 
RECEIVE  lamp  and  returns 
to  the  idle  mode  following 
reception  of  the  ETX  char- 
acter. 


The  software  presented 
below  causes  the  8800  to 
simulate  the  transmit  con- 
ditions which  existed  at  the 
Burroughs  B3501  (the 
Friden's  host  computer).  As 
can  be  seen,  the  requirements 
necessary  to  make  the  Friden 
accept  data  from  the  8800 
are  much  more  stringent  than 
the  conditions  required  to 
make  the  Friden  "talk"  to 
the  8800. 

The  Software 

For  explanatory  purposes, 
the  program  is  divided  into 
two  main  routines:  BUFF1N 
and  PRINT.  BUFF  IN  is  called 
up  by  the  output  routine  of 
my  MONITOR  program. 
{Any  general  output  routine 
can  be  used  to  call  BUFF  IN.) 
In  my  system,  as  the  MON- 
ITOR outputs  data  the  char- 
acters are  displayed  on  a  CRT 
display  and  stored  in  a  buffer 
area  in  the  8800 's  memory, 
for  eventual  transfer  to  the 
buffer  of  the  Friden.  When  a 
CR  character  is  detected, 
BUFFI N  calls  up  the  PRINT 
routine.  PRINT  is  responsible 
for  the  actual  transfer  of  data 
from  the  buffer  in  the  8800 
to  the  Friden's  buffer,  and 
for  the  generation  and 
transfer  of  the  "handshake" 
characters  described  pre- 
viously. BUFFIN  and  PRINT 
will  not  interfere  with  the 
outputting    of    data    to    the 

fj 

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CRT  display,  other  than 
causing  a  4  to  7  second  delay 
at  the  end  of  a  CR-terminated 
line.  This  time  is  consumed 
by  the  8800  transferring  data 
from  its  buffer  to  the 
Friden's  buffer,  and  for  the 


detection     of     the     Friden- 
generated  ACK  flag. 

Use  has  been  made  of 
memory  storage  and  the 
stack,  to  save  the  status  of 
some  of  the  registers  which 
are  redefined  when  BUFFI N 


and  PRINT  are  called.  The 
data  are  assumed  to  reside  in 

register  B  prior  to  calling 
BUFFI N,  The  program,  as 
presented,  resides  in  the  top 
1  K  of  my  9K  memory;  when 
you    relocate    it,    pay    close 


attention  to  the  memory 
references.  Nothing  can  make 
you  wish  you  had  taken  up 
another  hobby  faster  than 
having  to  track  down  an 
errant  memory  reference, 
As  you  study  the  program, 


BUFF  IN      Pg.  041  TOO 

345 

Push  H 

Save  main  mem  pointer 

034 

006 

MV[B 

Load  B  with  an  STX 

101 

041 

LXI  H 

Initialize  buffer  pointer 

035 

002 

102 

200 

036 

315 

CALL 

Call  the  output 

103 

041 

037 

Q50 

routine 

104 

160 

MovM.B 

Store  char  in  buffer 

040 

042 

106 

170 

Mov  A,B 

Move  char  to  Ace 

041 

07S 

OCR  A 

Decrement  the  Ace. 

106 

376 

CPI 

042 

062 

STA 

Store  decremented  Acc- 

107 

015 

Is  char  a  CR? 

043 

001 

in  Temporary  Storage  T 

no 

312 

JZ 

Yes,  go  to 

044 

042 

for  future  reference 

in 

121 

GOTCR 

045 

006 

wivi  a 

Retrieve  present  character  from 

112 

041 

TS3                          046 

XXX 

Temporary  Storage  3 

113 

043 

INXH 

No,  increment  pointer 

047 

311 

RET 

Return  \o  calling  routine 

114 

042 

SHLP 

store  buffer  pointer  (H&L  registers) 

OUTIT        Pg.  042050 

333 

IN 

Input  the 

115 

102 

In  address  102 

0&1 

006 

control  channel 

116 

041 

pg.  041 

052 

346 

AMI 

117 

341 

POPH 

Retrieve  main  mem  pointer 

053 

20O 

Ready? 

120 

311 

RET 

Return  to  calling  routine 

054 

312 

JZ 

No,  loop 

GOTCR                    121 

041 

LXI  H 

Set  buffet  pointer 

055 

050 

122 

200 

To  beginning  address 

056 

042 

123 

041 

of  buffer 

057 

170 

MOVA.B 

Output  the 

124 

042 

SHLO 

Store  buffer  address 

060 

323 

OUT 

character  to 

125 

102 

in  address  102 

061 

007 

terminal 

126 

041 

pg,  041 

062 

311 

RET 

Return  to  calling  routine 

127 

000 

NOP 

no  operations 

063 

000 

NOP 

No  operations 

130 

000 

NOP 

helpful  in  debugging 

064 

000 

NOP 

helpful  in  debugging 

131 

000 

NOP 

ditto 

065 

000 

NOP 

ditto 

132 

000 

NOP 

ditto 

066 

000 

NOP 

ditto 

NEXT          Pg.  041-133 

106 

MOV  B,M 

Get  char  from  buffer 

067 

000 

NOP 

ditto 

134 

315 

CALL 

CaH  up 

GENLRC                070 

356 

XRI 

Generate  the  LRC  character 

135 

000 

the  location  of 

TS  2                        071 

000 

Store  the  result 

136 

042 

the  PRINT  routine 

072 

062 

STA 

137 

176 

M0V  ATM 

Move  char  to  Ace 

073 

071 

in  TS  3  for 

140 

376 

CPI 

074 

042 

future  reference 

141 

015 

Is  char  iCR? 

075 

311 

ftET 

Return  to  calling  routine 

142 

312 

JZ 

Yes.  last  char 

076 

000 

NOP 

143 

151 

in  buffer,  90  to 

077 

000 

NOP 

144 

041 

LAST 

DUMP         %  042-100 

006 

MVI  B 

Load  B  with 

145 

043 

INXH 

Increment  pointer 

101 

003 

an  ETX  character 

146 

303 

JMP 

No,  fetch  next 

102 

315 

CALL 

Output  the 

147 

133 

char  in  buffer 

103 

050 

ETX  to 

150 

041 

by  going  to  NEXT 

104 

042 

the  terminal 

LAST                        1 51 

041 

LXI  H 

Initialize  buffer 

105 

315 

CALL 

Generate  final 

162 

200 

for  next  pass 

106 

070 

LRC  character 

153 

041 

107 

042 

for  this  pass 

154 

042 

Store  buffer  address 

110 

107 

MOV  B,A 

155 

122 

in  address  122 

111 

000 

NOP 

156 

041 

pg.  041 

112 

3T5 

CALL 

Output  the  LRC 

157 

341 

POPH 

Retrieve  main  mem  pointer 

113 

050 

160 

311 

RET 

Return  to  main  calling  routine 

114 

042 

PRINT        P&„  042-000 

076 

MVI  A 

Test  for  first 

115 

000 

NOP 

TS1                         001 

002 

call  of  PRINT 

116 

000 

NOP 

002 

376 

CPI 

during  this 

117 

000 

NOP 

003 

002 

past 

ACK  IT                      120 

333 

IN 

Input  the 

004 

314 

cz 

Yes,  go  to 

121 

006 

control  channel 

005 

030 

OUTSTX 

122 

346 

ANI 

006 

042 

123 

001 

Ready? 

007 

315 

CALL 

No,  output  the 

124 

312 

JZ 

No,  loop 

010 

050 

present  character 

125 

120 

0T1 

042 

126 

042 

012 

315 

CALL 

Generate  the 

127 

333 

IN 

Input  the 

013 

070 

LRC  character 

130 

007 

data  channel 

014 

042 

Pg.  042-131 

376 

CPI 

01S 

170 

MOV  A,B 

Is  present 

132 

006 

is  it  an  ACk 

016 

376 

CPI 

character  A 

133 

302 

No.  Loop 

017 

015 

CR? 

134 

120 

020 

312 

JZ 

Yes,  dump 

135 

042 

021 

100 

the  terminal's 

136 

076 

MVI  A 

Yes,  reset  PRINT 

022 

042 

buffer 

137 

002 

entrance  to  detect 

023 

311 

RET 

No,  return  to  BUFF  IN 

140 

062 

STA 

initial  call 

024 

000 

NOP 

No  operations 

141 

001 

of  next  pass 

025 

000 

NOP 

helpful  in  debugging 

142 

042 

026 

000 

NOP 

ditto 

143 

076 

MVI  A 

Clear  the  LRC 

027 

000 

NOP 

ditto 

144 

000 

character  address 

OUTSTX     Pg,  042  030 

170 

MOV  A+B 

Score  present 

145 

062 

STA 

031 

062 

STA 

character  in 

146 

071 

032 

046 

Temporary  Storage  3 

147 

042 

033 

042 

160 

311 

RET 

Return  to  calling  routine 

XA 


Table  h  Attair/Friden  interface  routines. 


102 


it  will  become  apparent  that 
the  main  calling  routine  could 
call  PRINT  directly,  circum- 
venting BUFF  IN.  You  may 
elect  to  do  so.  However,  if 
you  use  the  Friden  to  get 
hard  copy  while  you  are 
getting  soft  copy  on  a  CRT, 
you  may  have  problems. 
Some  programs p  such  as  those 
for  games,  may  only  output 
half  a  line;  they  may  then 
wait  for  an  operator  response 
before  finishing  the  line  and 
generating  the  CR  character. 
This  is  OK  on  a  CRT  display, 
where  printout  is  instan- 
taneous {well,  almost  instan- 
taneous) and  not  being  timed. 
But  remember  that  the 
Friden  has  a  25  second  timer 
which  starts  with  the  recep- 
tion of  the  STX  character.  If 
the  ETB/ETX  and  LRC  char- 
acters are  not  received  in  the 
25  second  interval,  a  TIME- 
OUT-ERROR condition  will 
be  displayed.  Consequently, 
i lie  FriderVs  buffer  will  be 
cleared  and  no  printout  will 
be  obtained.  Use  of  BUFFI N 
ensures  the  existence  of  a  CR 


character  in  the  8800ps 
buffer,  and  the  generation  of 
the  all-important  ETX  and 
LRC  characters  by  PRINT, 
within  the  timed  interval. 
Alas,  this  is  one  shortcoming 
of  this  configuration  of  the 
Friden;  it  isn't  particularly 
suited  to  interactive  work. 

Conclusion 

Well,  there  it  is.  It  isn't  the 
most  efficient  program, 
memory-wise.  (I  don't  profess 
to  be  a  programmer.)  But  it 

does  work,  and  the  Friden 
produces  a  hard  copy  with  a 
style  all  its  own.  Before  con- 
figuring it  to  your  system,  be 
certain  that  you  understand 
"everything"  in  the  program, 
1  wouldn't  want  to  see  any- 
body have  to  put  the  days 
(and  sleepless  nights)  into  this 
project  which  I  put  into  it. 
Actually,  it  was  fun,  but  it 
had  its  moments. 

Good  luck  with  it.  If  you 
have  any  difficulties,  send  an 
SASE  and  I  will  try  to  help 
you  out*  Keep  on  com- 
puting! ■ 


Best  for  beginners .  - .  preferred  by  pro's! 

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BROADCAST 

RECEIVERS 


INTERS fAGE    SHIELD 


RF    AMPLlFtER 


POWER 


Fig,  L  Two  meter  to  broadcast  band  converter,  L I:  2  turn  link  on  low  end  of  L2+  L2:  4  turns 
#20  on  7  mm  slug-tuned  form  spaced  to  5  mm;  tap  at  116  turns  from  low  end.  L3f  L4:  3  turns 

#20  on  7  mm  slug-tuned  form  spaced  to  5  mm.  LS:  20  turns  #30  closewourtd  on  4  mm  solid 
ferriie  form.  YJ:  48.5  MHz  third  overtone  crystal,  HC25JU  holder  (see  text). 


J.  R.  Johnson  WA5RON 
4558  Ave.  A  #205 
Austin   TX  78  75  J 


Another  converter?  Well, 
maybe  there  have  been 
an  awful  lot  of  converter 
designs  published  in  these 
pages,  but  take  a  careful  look 
at  this  one  before  you  say 
you  don't  need  a  converter. 
The  unit  described  here  is 
designed  to  let  you  tune  a  1 


New  Improved 
Repeater  Monitor 


--1  transistors 


106 


MHz  band  on  two  meters 
using  your  automobile  radio. 
Even  if  you  already  have 
VHF  gear  in  your  car, 
chances  are  that  you  can  only 
receive  at  a  few  crystal  fre- 
quencies, and  you  would 
appreciate  being  able  to  tune 
the  band  to  see  what  is  going 
on.  You  could  also  use  this 
converter  in  a  rented  car, 
your  wife's  car,  or  for  one 
way  communication  when 
traveling  with  other  {non- 
radio  equipped)  vehicles  on 
the  road.  I  suppose  that  you 
could  even  build  it  for  the 
police  frequencies  or  other 
VHF  services. 

I  thought  of  building  this 
converter  one  day  when  I 
noticed  the  push-button  AM 
radio  mounted  nicely  in  the 
instrument  panel  of  my  auto- 
mobile, and  realized  that  it 
had  not  been  turned  on  for  at 
least  two  years  (if  you  reside 
in  Texas  but  don't  like  cow 
music,  the  AM  broadcast 
band  has  little  to  offer).  I 
thought  how  nice  it  would  be 
if  the  coverage  of  that  re- 
ceiver were  in  one  of  the  ham 
bands  instead  of  300  meters, 
and  I  decided  right  there  to 
build  a  converter. 

I  found  a  simple  converter 
design  in  an  issue  of  731 ,  and 
quickly  built  one  up  as  in  the 
article.  The  unit  worked,  a 
two  meter  QSO  on  one  of  the 
repeaters  was  heard,  but  it 
was  competing  (and  losing) 
with  all  the  50  kW  cow  sta- 
tions that  were  there,  hardly 
attenuated  at  all  by  the  con- 
verter in  the  antenna  line.  It 
appeared  to  me  that  any  con- 
verter I  built  to  work  into  the 
broadcast  band  as  an  i-f 
woufd  have  to  have  consider- 
able isolation  between  input 
and  output,  and  that  at  least 
one  stage  of  rf  amplification 
ahead  of  the  converter  was 
certainly  desirable.  The 
design  that  evolved  is  note- 
worthy in  its  attention  to 
shielding,  compartmentaliza- 
tion,  and  rf  blocking  along 
the  power  lead,  considera- 
tions that  are  necessary  in 
preventing  the  bleed-through 
of  broadcast  stations.  Fortun- 
ately, automobile  radios  are 
already     well     shielded    and 


Converter  interior  is  divided  by  copper  shields  into  four  compartments.  Block  of  foam-rubber 
glued  to  case  half  keeps  the  battery  in  its  clip  on  bumpy  roads. 


bypassed!  and  they  make  sen- 
sitive i-f  receivers  with  plenty 
of  audio  output. 

A  5.5  x  7.5  x  13.5  cm  Bud 
mintbox  was  divided  into 
four  compartments  by  shields 
cut  from  sheet  copper  (hobby 
or  arts  and  crafts  shop).  A 
,001  uF  feedthrough  capaci- 
tor is  mounted  in  each  of 
these    shields    to    pass    (and 


bypass)  the  power  lead,  and 
two  of  the  shields  are  also 
fitted  with  an  insulated  feed- 
through  (a  grommet  will  do) 
for  rf.  The  four  compart- 
ments contain  preamp,  oscil- 
lator, mixer,  and  power 
supply.  This  last  is  a  9  volt 
battery  that  will  run  for  a 
long  time  at  25  mA  drain, 
providing   you   remember  to 


turn  the  unit  off  when  not  in 
use. 

The  preamp  is  a  non-FET 
design  found  in  Japanese 
VHF  receivers,  with  a  link- 
coupled  input  circuit  added 
to  discourage  the  beastly 
broadcast  band  from  getting 
deep  into  the  converter.  If 
you  don't  have  a  25A239 
lying  around,  then  any  of  the 


Converter  sections  are  (left  to  right):  J  —  input  and  rf  amplifier  stage,  2  —  Crystal  controlled 
oscillator,  3  —  Mixer  stage  and  output,  4  —  Battery  and  switch 


107 


Shielding  and  separation  of  input  and  output  sections,  plus  elaborate  bypassing  of  low 
frequency  signals  on  both  rf  and  power  leads  is  necessary  to  keep  powerful  broadcast  stations 
from  shoving  their  interference  through  the  converter. 


''equivalent1'  transistors  they 
sell  nowadays  in  the  whole- 
sale stores  should  work.  I 
tried  a  GE-9  and  it  did  just 
fine.  Component  leads  must 
be  very  short  or  they  will  add 
inductance  in  series  with  the 
coils,  which  are  quite  small. 
Ground     points     can     be 


soldered     directly     to     the 

copper  shield. 

The  oscillator  was  wired 
together  on  a  small  piece  of 
vector  board,  held  by  machine 
screws  and  short  standoffs  to 
the  copper  shield.  The  oscilla- 
tor stage  was  put  between 
amplifier  and  mixer  to  maxi- 


mize the  physical  separation 
between  input  and  output,  A 
third  overtone  crystal  in  the 
48-49  MHz  range  is  em- 
ployed, giving  a  third  har- 
monic at  two  meters  that  is 
used  by  the  mixer  stage. 
Choose  a  crystal  frequency 
such  that  when  multiplied  by 


The  oscillator  board  mounted  on  one  side  of  a  shield.  Crystal  socket  and  miniature  crystal  are 
the  only  components  on  the  backside  of  the  board.  Power  feed  through  capacitor  is  at  upper 
right  and  insulated  feedthrough  tor  the  rf  line  is  below.  Mixer  stage  (part  of  coil  visible  at 
bottom)  is  on  the  reverse  side  of  shield. 


three,  the  resultant  frequency 
is  600  kH>!  below  the  bottom 
oT  the  range  you  would  like 
to  tune.  For  example,  if  you 
wish  to  tune  the  popular  FM 
frequencies  between  146  and 
147,  a  crystal  near  48.4667 
could  be  selected.  The  third 
harmonic  would  be  145.4, 
putting  146  at  the  600  kHz 
mark,  and  147  at  1600,  This 
should  be  fine  for  locating 
repeaters  in  unknown  towns 
as  you  travel  about,  or  just 
keeping  tabs  on  local  FM 
activity.  If  you  would  like  to 
preserve  the  usefulness  of  the 
original  dial  calibrations,  then 
you  need  a  crystal  cut  for 
48,6667  (146.0),  This  will 
put  146,55  MHz  at  the  little 
"55"  on  the  dial,  and  147.6 
will  come  in  at  **160"  or 
li16"  or  whatever  you  have  at 
the  top  end.  When  you  order 
a  crystal,  include  a  drawing  of 
the  oscillator  schematic,  and 
tell  the  manufacturer  what 
third  harmonic  frequency 
you  want  to  get,  as  well  as 
the  4S  MHz  third  overtone 
frequency. 

You  will  note  that  the 
tuned  circuits  in  this  con- 
verter have  both  variable 
capacitors  and  slug-tuned 
coils.  This  allows  one  to 
roughly  peak  the  circuits 
using  the  capacitors  with  the 
box  open,  and  then  fine  tune 
all  stages  after  the  unit  is 
closed  up  and  mounted  in  the 
vehicle.  Cut  a  length  of 
antenna  cable  to  go  between 
converter  and  radio,  with  a 
Motorola  plug  on  one  end 
and  a  BNC  on  the  other.  The 
car's  telescoping  whip 
antenna  will  work  just  fine 
when  pushed  down  to 
quarter  wavelength,  and  if  the 
feed  line  is  replaced  with 
RG  58  or  RG-59.  The  original 
automobile  antenna  cable 
seems  to  be  some  sort  of 
cheapo  shielded  stuff  with  a 
kinky  wire  for  a  center  con- 
ductor, I  suspect  that  it  was 
not  intended  for  VHF,  and 
certainly  not  very  good  for 
transmitting. 

Many  new  cars  seem  to 
come  with  a  solid  steel  whip. 
This  could  be  used  as  is,  but 
cutting  it  to  quarter  wave- 
length    will     improve     VHF 


108 


reception  and  broadcast 
image  rejection.  I  can't 
recommend  those  imbedded- 
i  n-  the- windshield  type 
antennas  at  all.  This  novelty 
was  foisted  on  the  car  buyer 
at  about  the  same  time  as  the 
something- else- to-malfunc- 
lion  hideaway  headlight.  If 
you  got  stuck  with  one  (or 
both)  of  these,  you  might  as 
well  punch  a  hole  and  mount 
a  decent  two  meter  antenna. 
After  all,  you  are  a  ham, 
aren't  you? 

Plug  the  converter  in  and 


tune  up  the  circuits  on  a 
signal  somewhere  near  the 
middle  of  the  band.  Look  for 
the  antenna  trimmer  capaci- 
tor on  the  broadcast  radio 
and  tune  for  maximum  signal 
reception.  This  capacitor  may 
be  found  near  the  antenna 
input  connector,  or  behind  a 
hole  above  the  tuning  shaft 
that  can  be  reached  by 
pulling  a  knob  (instead  of 
pulling  the  whole  radio).  This 
adjustment  does  make  a 
difference. 

My  little  converter  should 


give  you  good  reception  on 
two  meters  of  both  AM  and 
FM  stations.  The  ability  of 
the  automobile  radio  to 
slope-detect  FM  depends 
upon  the  sharpness  of  its  i-f 
tuning.  I  found  that  I  was 
able  to  improve  the  tuning 
and  tracking  across  the  band 
of  both  i-f  and  rf  stages 
within  the  receiver  by  tweak- 
ing on  the  slugs.  Getting  the 
radio  out  and  back  into  most 
modern  automobiles  is  made 
easier  by  turning  the  vehicle 
upside  down  and  moving  the 


firewall  forward  a  few  feet. 

You  might  even  go  so  far 
as  to  cut  into  the  original  AM 
board  and  add  one  of  the  FM 

limiter  and  discriminator  inte- 
grated circuits.  I  think  that 
you  will  find,  however,  that 
FM  reception  is  quite 
acceptable  without  any  modi- 
fication to  the  broadcast  re- 
ceiver. ■ 

Reference 
l 


i  # 


Build  the  OTC,"  John 
Crawford  WA4SAM,  George 
Webber  W1DVG,  73  Magazine, 
January,  1966r  page  74. 


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CHECK  THESE  FEATURES 

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2  meter  FMt  10  channels,  30  watts 
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4141  Kingman  Dr.,  Indianapolis,  IN  46226 
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Q  6TX-2M      $J9995 


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Q  Lambda/4  2-M  and  G-M  Trunk 
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Cf  OAoe  ^  ^""  Tone  £nco,ler  ^ 

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antf  the  following  statfari  crystals 

$70095    3**50  each $_ 

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j 


110 


SPECIFICATIONS 


GENERAL: 
Front  Panel  Size;  6WfK2V2ff 

Over-all  Dimensions;  lOVa"  deep  x 
GV2"  wide  x  zi/a"  high 

Components:  13  Transistors,  10  Diodes. 
6  FETS,  4  ICs 

Frequency  Range:  144  to  148  mHz 

Number  of  Channels:  20  plus  2 

Weight:  Approximately  6  lbs. 

Power  Supply:  13.75v  DC  system, 
negative  ground 

RECEIVER; 

Sensitivity: 

12  cfb  SINAD;  .25  Microvolt 

Selectivity:  ±7,5  KHzP  @  6  db  or  less 
Squelch  Threshold:  0.1  Microvolt 

Modulation  Acceptance:  More  than  5  KH;j 

Adjacent  Channel  Rejection r  More  than 
85  db  (  +  30KH2) 

Intermod  response;  More  than  70  db 

image  Responses:  More  than  7D  db 

Spurious  Response:  More  than  70  db 

Audio  Output  Power:  4  Watts  at  less 
than  15%  distortion  (5  Watts  Max) 

Frequency  Stability:  ±.001% 

Circuit  Type:  Double  conversion, 
Superheterodyne.  Crystal  Controlled, 
3  Pole  Crystal  Filter 

Intermediate  Frequencies:  10,7  mHz 
1st  IF;  455  KHz  2nd  IF 

Current  Drain:  (Squelched)  .2  Amps. 

FCC  Certified;  Part  15,  subpart  C 


Just  Unpack  the  GTX-202  and 

Channel  in  for  the  Holidays  . 


The  GTX-202  is  adaptable  anywhere— at  half  the 
price  of  Synthesis — So,  buy  at  low  acquisition  cost, 

and  add  crystals  later  as  you 

want  or  need  them. 


s*sL 


.■£■■:-'#' 


*°*30  e»y 


eacfj 


TRANSMITTER; 

Power  Output:  Hi:  30  Watts  nom.T 
25  Watts  m!n.T  @  14v  DC  input 
Lo:  1  Watt  @  14v  DC  input 

Output  Impedance:  Matches  standard 
50  Ohm  amateur  antennas 

Frequency  Stability:  ±.001% 

Audio  Modulation  Deviation:  Adjustable1 

to  10  KHz  max. 

(Factory  set  to  ±5  KHz] 

Current  Drain;  Hi,  6.0  Amps*  Lo  1.7  Amps. 


"**, 


f 


r**** 


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USE  THIS  HANDY 
ORDER  FORM 


□  GTX-202 


2-Meter  FM 
22  Channels 


H  Ringo  Ranger  ARX-2  6  db  2-M  Base  Antenna 

@  $29.95  $ 

D  Lambtfa/4  2-M  and  fi-M  Trunk  Antenna 

@  $29-95  $ 


□  TE-f  Tone  Encoder  Pad  for 
plug-in  installation  on  most 
amateur  transceivers    @  $59.95  $. 


D  TE-II  Tone  Encoder  Pad  for  installation  on 

most  Hand-Helds  @  $49.95  $ 

G  PS-1  AC  Power  Supply  for  use  with  all  makes 

of  transceivers  14  VDC-6  amps      @  $69.95  $ 

and  the  following 

Standard  crystals  @  $4.50  each  $ 

NoR-Standard  crystals  @  $6.50  each  $ 

Payment  by: 
n  Certified  Check/ Money  Order    D  Personal  Check 
□  CO.D,  Include  20%  Down 

Note:  Orders  accompanied  by  personal  checks  will  require 
about  two  weeks  to  process. 

20%  Down  Payment  Enclosed.  Charge  Balance  To; 

□   BankAmericard  # Expires 

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d  Interbank  # Expires 

IN  residents  add  4%  sales  tax: 


CA  residents  add  6%  sales  tax 


:} 


$- 


Aft  orders  shipped  post-paid  within  Continental  U.S* 
Add  $4-  per  Radio  for  Shipping, 
Handling,  and  Crystal  Netting. 


Check  these 

outstanding 

features:  ^ 

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« — L-I^f^^nt  end 

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Be  sure  to  look  for 

MAUL    Ifl 

the     [Js      tag, 


4141  Kingman  Dr.,  Indianapolis,  IN  46226 

Phone-in  orders  accepted  (317+546-1111) 


i 


NAME. 


ADDRESS. 


CITY. 


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AMATEUR  CALL 


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self-contained     unit    for 
additional  $10, 


an 


Put  Snap  in  Your 
SSTV  Pictures 


-  -  using  a  $20  freq  standard 


E.  Sommerfield  W2FJT 
49 Spring  Road 
Poughkeepsie  NY  12601 


Frequency     measurement 
has  always  been  an  ex- 
pensive problem  for  the  radio 

amateur;  the  least  expensive 
frequency  counter  costs 
about  $150.  Frequency 
measurement  by  counting  is 
not  the  only  method  of 
measurement,  however. 
Another  less  expensive,  and 
equally    accurate,   alternative 


for    specific    applications    is 

called  frequency  comparison. 
This   article    will    describe  a 

crystal  calibrator/comparator 
for  SSTV  that  will  permit, 
adjustment  of  various  SSTV 
frequencies  to  within  1  Hz 
for  as  little  as  $20.  The  cali- 
brator can  either  be  built  into 
the  Robot  Research  80A 
camera,  or  implemented  as  a 


2O720GH* 


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U4-I.2 

G5C 


-HMC777P 


KC77TP 

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MODIFICATION 


<§" 


FROM  US-6  (C33) 
SSTV  OUTPUT 


Fig,  /,  Overview  of  crystal  dear  f  200  Hz. 


Overview 

The  basic  requirement  in 
any  frequency  comparison 
system  is  an  accurate  fre- 
quency source.  One  such 
source  is  a  crystal  oscillator  in 
the  1200  Hz  to  2300  Hz 
range.  Crystals  in  this  fre- 
quency range  are  somewhat 
difficult  to  fabricate;  how- 
ever,  crystals  in  the  256th 
multiple  of  this  range  (300 
kHz  -  600  kHz)  are  easily 
obtained.  All  that  is  required 
is  a  division  by  256,  and  a 
frequency  comparator. 

In  both  the  80A  and  self- 
contained  versions  (Fig.  1)t  a 
crystal  controlled  square 
wave  generator  at  307,200  Hz 
(1200  Hz  x  256)  is  fed  into  a 
256  divider  chain  and 
emerges  as  1200  Hz.  This 
1200  Hz  signal  is  then  com- 
pared to  the  1200  Hz  SSTV 
video.  The  resultant  "beat 
note"  is  displayed  on  an  LED 
(Light  Emitting  Diode). 

In   the   80A  version  Fig, 

1  (b),  the  divider  chain  in  the 
NORMAL  mode  is  used  to 
convert  the  15  Hz  horizontal 
input  to  a  1/8  Hz  (8  second) 
vertical  signal  by  dividing  by 
128;  the  last  couniing  posi- 
tion is  not  used.  In  the  COM- 
PARE mode,  the  input  to  the 
256  divider  chain  is  changed 
to  307,200  Hz  and  the 
output  at  1200  Hz  is  taken 
from  the  last  position.  The 
same  "beat  note"  detector  is 
used.  If  operation  at  2300  Hz 
is  desired,  a  crystal  frequency 
of  588,800  Hz  would  be  re~ 
quired.  Since  crystals  in  this 
frequency  range  cost  $37,50, 
a  crystal  at  1/2  the  fre- 
quency, 294,400  Hz,  costing 
$13.50  is  used,  and  the 
output  is  taken  at  the  divide 
by  128,  the  next  to  the  last, 
divider  position* 

CIRCUIT  DESCRIPTION 

The  oscillator  and  compar- 
ator are  both  contained  in  an 
RCA  CA-3046  5  transistor 
DIP  module. 

Oscillator 

The  oscillator  is  a  standard 

2  transistor     free-running 


112 


multivibrator  in  which  one  of 
the  RC  networks  has  been 
replaced  by  a  crystal.  The 
free-running  frequency, 
originally  controlled  by  the 
RC  networks,  is  now  con- 
trolled by  a  .01%  tolerance 
crystal.  The  maximum  crystal 
error  is  30  Hz  at  307,200  Hz, 
When  the  frequency  is 
divided  by  256,  the  error , 
which  is  also  divided  by  256, 
becomes  .12  Hz;  this  is  far 
more  accurate  than  any  SSTV 
requirements.  The  output  of 
the  oscillator  is  a  square  wave 
which  when  loaded  is  about 
1.0  volts  to  1.7  volts  at 
307,200  H2.  The  oscillator 
was  designed  to  have  a  mini- 
mum loading  effect  on  the 
+3.6  volt  regulated  supply 
(80A).  The  80A  +3.6  volt 
supply  already  has  about  a 
200  mA  load,  and  the  regu- 
lator transistor  is  "hot'*  to 
the  touch. 

Comparator 

The  comparator  is  com- 
posed of  2  inverters  with  a 
common  collector  load  re- 
sistor and  shunting  LED.  The 
LED  has  a  minimum  voltage 
threshold  of  about  +1 .2  volts, 
Current  will  flow  in  the  LED 
only  when  BOTH  transistors 
UA-3  and  UA-4  are  off.  The 
amount  of  time  that  both  are 
off,  and  in  turn  the  LED  is 
illuminated,     depends     upon 


FOR 

23DQHI 
USE  ft 


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Rll 
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RIZ 
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J-v* — 
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3,6JJ 


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4 .711 


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1 


SSTV     C3 

*  Brlf 


Fig.  2  Self-contained  crystal  clear  1200  Hz.  Ul  -  RCA  CA3046;  U2,  U3-  Motorola  MC777P; 
SJ  -  Archer  2751386;  LED  -  Archer  276-041;  S2  -  Caiectro  E2-140;  Rl-RW  -  %  W  10%; 
RJ1-R16  -  %  W  10%;  Dl  -  Archer  276-612  or  276-114;  chassis  box  -  Caiectro  H4-742; 
battery  holders  —  1  cell,  Caiectro  D3062;  2  cell,  Caiectro  D3063.  Caiectro  =  Lafayette,  Archer 
=  Radio  Shack.  *R6  was  designed  for  an  80 A  output  greater  than  2  V  p-p  and  a  low  output 
source  impedance.  X  —  see  Crystal  Specifications. 


the  frequency  relationship  of 
the  1200  Hz  crystal  con- 
trolled reference  frequency 
and  the  SSTV  input  fre- 
quency. As  the  two  signals 
"beat11  together,  the  LED  will 
"flicker"  at  the  rate  of  the 
difference  frequency.  Since 
the  two  signals  will  rarely 
lock  together  at  the  same 
frequency,  there  will  always 
be  some  flicker.  The  compar- 
ator output  when  no  SSTV 
video  is  inputted  consists  of  a 
1200  Hz  square  wave  of 
about  1  volt  p-p.  This  signal, 
with  a  very  low  source  impe- 
dance,  is  ac  coupled  to  the 


.I3H*  FR0W 

r~s  ub-1  or  a 


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R7 
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■<  SSTV  FROM  tf5-S  (C33) 


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FROM 

UIO  6  t296 

UIO  ft  *  '2ft 


Fig.  3.  80A  modification.  All  resistors  except  R8  can  he  as  ft)M 
as  %  Watt  10%.  Ul  -  RCA  CA3046;  LED-  Archer 276-041 ; 
SI  -  Caiectro  E2-1Q5;  C2  -  Caiectro  Al-l25;X-see  Crystal 
Specifications;  term  strip  —  Caiectro  F3214.  Caiectro  = 
Lafayette,  Archer  =  Radio  Shack, 


output  jack,  )  2,  and  can  be 
used  as  a  1200  Hz  signal 
generator. 

Divider  Chain  (Self-Contained 
Only) 

The  divider  chain  in  the 
sel Contained  version  is  iden- 
tical to  the  one  used  in  the 

80A,  and  consists  of  two 
Motorola  MC777P  binary 
counters  connected  in 
tandem,  Since  the  divider 
chain  counters  are  unloaded, 
I  found  that  the  most  reliable 
operation  was  obtained  at 
about  +3.2  volts, 

Switch  (80A  only)  Fig.  3 

Many  methods  were 
analyzed  in  order  to  find  a 
method  of  injecting  the 
307,200  Hz  signal  into  the 
80A  divider  chain  without 
disturbing   the   land   pattern. 


The  only  solution  found, 
however,  was  to  "break*1  the 
land  pattern  on  the  back  of 
the  component  board  as 
shown  in  Fig.  4.  Leads  to  the 
modification  can  be  run  from 
either  the  land  pattern  on  the 
back,  or  touch  soldered  from 
the  pins  of  the  DIP  modules 
on  the  front,  depending  on 
the  skill  of  the  user. 

The  switch,  SI,  provides 
the  means  by  which  the 
307,200  Hz  signal  is  injected 
into  the  divider  chain. 

Power  Supply  (Self-Con- 
tained Only) 

The  divider  chain,  un- 
loaded in  this  application, 
works  optimally  at  about 
+3.2  volts  ±  .2  volts.  The  load 
current  is  about  150  mA.  A 
power  supply  could  have 
been    constructed   for   about 


TOP 


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IPEaic 


-5 


fO  v-«    4, 


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Fig.  4*  80A  land  pattern  modification.   Wiring  (back)  side  of 
board. 


113 


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R2- 


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SCALE 


TO  IN  PUT  JACK 


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F/£.  5.  Self-contained  perfhoard  component  locations. 


$10,  but  the  intermittent  use 
of  this  unit  pointed  to  the  use 
of  a  battery  supply  for  about 
$1.  In  order  to  obtain  maxi- 
mum use  of  the  battery  as  Its 
voltage  decreases  with  age 
and  use,  a  variable  resistor,  or 
as  in  my  case,  a  switch  with 
resistors  (Fig.  2),  was  used  to 
permit  adjustment  of  the 
supply  voltage.  Too  high  a 
supply  voltage  causes  a  2400 
Hz  output;  too  low  a  voltage 
results  in  no  output.  The  cor- 
rect voltage  is  easily  obtained 
by  first  connecting  earphones 
to  the  1200  Hz  output  jack, 
J2,  and  then,  starling  at  the 
maximum  resistance,  slowly 
reducing  the  resistance  until 
the  1200  Hz  signal  is  heard, 

CONSTRUCTION 

Self-Co  ntained 

The  self-contained  version 
layout  is  shown  in  Fig.  5  and 
the  photograph.  It  is  con- 
structed on  a  2.5"  x  6"  piece 
of  J  00  x  ,100  inch  perf board 
(Archer  -  Radio  Shack  — 
#276-1394),     R11-R16     are 


mounted     on     the     chassis, 

supported    between    SI    and 
S2. 

80A 

The  80A  layout  requires 
more  effort,  but  it  has  the 
advantage  of  a  more  built-in 
feature.  Fig.  6  shows  the  loca- 
tion of  the  components.  The 
crystal  socket,  switch  SI,  and 
the  module  DIP  socket  were 
epoxied  onto  the  component 
board.  The  terminal  strip  was 
anchored  using  the  screw  that 
attaches  the  component 
board  to  the  camera  chassis. 

Operation 

Adjust  the  80A  output 
control,  R50,  to  2/3  full  scale 
(self-contained     only).     In 

order  to  measure  only  1200 
Hz,  the  SSTV  voltage  con- 
trolled oscillator  (VCO)  must 
first  be  forced  into  a  1200  Hz 
only  mode.  This  can  be  done 
in  the  80A  by  shorting  the 
collector  of  Q8  to  the  emitter 
of  Q8,  by  grounding  the  junc- 
tion   of    resistors    R34,    R35 


and  R134,  This  method  will 
result  in  a  sync  frequency  of 
about   1190  Hz,  The  reason 

for  the  10  Hz  difference  is 
that  the  normal  "on"  condi- 
tion for  Q8  is  not  a  shorted 
collector  to  emitter,  but 
rather  a  .1  volt  collector  to 
emitter,  Since  the  more  posi- 
tive the  collector  of  Q8  is 
from  -15  volts,  the  lower  the 
frequency,  0.0  volts  =  1190 
Hz,  whereas  0.1  volts  -  1200 
Hz, 

After  the  1200  Hz  only 
condition  is  satisfied,  adjust 
R42,  SYNC,  so  that  the  LED 
just  barely  flickers.  This 
setting  will  result  in  about 
1210  Hz  when  the  short  is 
removed.  If  a  more  accurate 
adjustment  is  desired,  re- 
adjust R42  away  from  zero 
beat  in  a  clockwise  direction 
so  that  the  LED  flickers  at 
about  10  beats/second,  and 
then  remove  the  short.  This 
should  result  in  an  output 
very  close  to  1200  Hz, 

Important  Note  (80 A  Version 
Only) 

In  the  compare  mode,  the 
1/4,  FULL,  1/2  vertical  scan 
switch  must  be  in  the  FULL 
scan  position  in  order  to 
allow  the  divider  chain  to 
divide  by  256, 

Crystal  Specifications 

The  crystal  used  in  my 
model  was  ordered  from 
International  Crystal  Mfg.  Co. 
Inc.,  10  North  Lee,  Okla- 
homa    City     OK     73102, 


according  to  the  following 
specifications  for  1200  Hz 
output:  Frequency  — 
307,200  Hz,  .01%  tolerance; 
Type  -  GP;  Calibration  — 
room  temperature;  Holder  — 
F605  (HC  6/U);  Circuit  Load 
-  use  Fig.  2. 

The  frequencies  for  other 
SSTV  outputs  are: 


OUTPUT 
1 200  Hz 
1 500  Hz 
2300  Hz 


CRYSTAL     ■ 
307,200  Hz 
384,000  Hz 
294,400  Hz 
(divide  by  128) 


Other  Configurations 

Other  configurations  that 
used  the  crystal  controlled 
1  200  Hz  output  signal  ^ted 
directly  into  the  SSTV  out- 
put during  sync  time  were 
considered  and  analyzed.  The 
80 A  VCO  mode  was  found  to 

maintain  more  than  sufficient 
stability  at  considerably  less 
cost.  These  other  designs  are 
available  by  SASE. 

Conclusion 

The  calibration  capability 
described  in  this  article  pro- 
vides the  missing  link  towards 
ease  in  obtaining  accurate 
alignment  of  not  only  the 
SSTV  camera,  but  also  the 
SSTV  station  monitor.  An 
A-B  comparison  using  the 
crystal  controlled  source  cali- 
bration vs.  a  Yaesu  model 
YC-355D  has  shown  no 
significant  difference  in 
accuracy,  but  a  substantial 
difference  in  cost.  ■ 


-Lit 


-T3 


CJ4 


■■ 

Til  ^TfN  (tc  iEFOTf  r*M»Ti*4 

1 


pxus  p*ri 


I 
9 

H 

* 


Fig.  6,  80 A  component  positioning. 


114 


only 

SQ95 


PP2 


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Baudot  via  a  FROM,  ASCII /Baudot  via  PROMs,  A  Second  Way  ,  .  ,  plus  reprints  of  some  of  the  73  editorials  on 

computers  such  as  Computermania,  The  Great  Computer  Peril,  Yes,  But  Which  Kit?,  Computer  Publications,  Ham 

Computing,  Postal  Disaster,  Programs  for  Sale?  These  are  reprints  from  73,  gathered  in  one  place  to  tie  the  whole  works 

together  for  you.  Don't  miss  out  any  longer  on  the  fun  of  hobby  computing  and  the  fantastic  ham  applications  of  these 

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The  advent  of  digital 
electronics  in  amateur 
radio  has  paved  the  way  for  a 
new  method  of  construction 
practice  already  widely  used 
in  industry.  This  is  called  the 
Wire-Wrap*  method.  One 
might  ask,  why  Wire-Wrap? 
Just  talking  about  the 
number  of  lines  coming  from 
an  IC  could  make  one's  head 
reel.  For  example,  let  us 
assume  that  we  have  thirty  16 
pin  ICSj  and  that  we  have  just 
one  wire  per  pin  as  either  a 
voltage,  a  ground,  or  a  signal 
line.  We  now  have  16  x  30,  or 
480  lines  to  interconnect. 
Can't  you  just  picture  the 
complexity  of  the  printed 
circuit  board  required  to 
accommodate  such  a  circuit? 
Note  that  Pm  talking  about  a 
16  pin  IC  in  this  case.  Now 
we  are  well  into  LSI  and  MSI 
with  24,  36,  or  40  pin  ICs 
becoming  very  popular,  This 
is  one  reason  why  industry 
has  gone  the  Wire- Wrap  route. 
The  mechanical  design  effort 
in  laying  out  such  a  PC  board 
is  a  time-consuming,  costly 
operation.  Most  of  the  time  a 
double-sided  PC  board  with 
plated-through  holes  would 
have  to  be  used.  And  in  even 
more     complex     circuits, 


Burt  YeUin  K2STV 
30  Eleanor  Lane 
Plainview  NY  11803 


What's  Al  I  This 


Wire- Wrap  Stuff? 


--talk  about  cold  solder  joints! 


i 


*The  term  "Wire-Wrap"  is  a 
registered  trademark  of 
Gardner-Denver  Co. 


multi-layer     boards     would 
have  to  be  designed, 

A  second  advantage  of 
Wire-Wrap  over  PC  is  the  ease 
with  which  a  design  change 
can  be  accomplished.  All  one 
needs  to  do  is  unwrap  the 
wire  and  put  the  new  one  in 
between  the  proper  two 
terminals.  We  all  know  what 
it  is  like  to  modify  a  PC 
board.  I  have  several  scarred 
fingers  from    a   slip    of   the 


knife  as  proof, 

Now  let's  talk  about  some 
of  the  electrical  and 
mechanical  attributes  of 
Wire-Wrap.  A  Wire-Wrap 
connection  consists  of 
approximately  seven  turns  of 
30  AWG  solid  copper  wire. 
The  wire  is  wound  about  a 
0.025  inch  square  terminal  in 
a  helical  manner,  without  the 
aid  of  solder.  As  the  wire  is 
wound   about   the   terminal. 


the  corners  of  the  terminal 
bite  into  the  wire,  as  the  wire 
notches  the  sharp  corner  of 
the  terminal.  In  this  manner, 
a  gastight,  oxidationfree  joint 
exists  between  the  terminal 
and  the  wire.  As  the  connec- 
tion ages,  a  solid  state  diffu- 
sion process  takes  place, 
which  enhances  the  mechani- 
cal strength  of  the  connec- 
tion. Through  exhaustive 
tests  it  has  been  determined 


Fig.  L 


J&    M 


n  ^ 


Fig.  2 


that  a  Wire-Wrapped  connec- 
tion has  a  life  expectancy  in 
excess  of  forty  years.  This 
tremendously  exceeds  the 
reliable  life  of  a  solder  con- 
nection, 

Wire-Wrapping  can  be 
accomplished  through  several 
methods.  There  are  hand 
Wire- Wrap  tools  which  are 
readily  available  and 
inexpensive.  If  many  wraps 
are    to    be    done,    I    would 

electrical    hand 
a  small   run   of 


suggest    the 

gun;   where 


similar     boards    are     to    he 


Wire-Wrapped,  there  is  the 
semi-automatic  method.  A 
"head"  with  a  Wire- Wrapping 
bit  Is  indexed  over  the  proper 
terminal  through  the  use  of  a 
numerical  controller.  The 
fully  automatic  method 
would  be  chosen  on  a  large 
run  of  similarly  Wire-Wrapped 
boards. 

Let's  go  through  a 
step-by-step  procedure  to 
show  the  simplicity  of  the 
Wire- Wrap  process; 

Step  1 .  Insert  the  stripped 
end  of  the  wire  into  the  tool, 


the     tool 
over     the 

t  he    tool 


as  shown  in  Fig,  1 . 

Step     2,   Place 
with     the     wire 
terminal  (Fig.  2). 

Step  3,  Twist 
clockwise,  until  the  stripped 
portion  of  the  wire  is  used  up 
in  the  wrap. 

Fig,  3  shows  a  completed 
"modified"  wrap,  "Modified" 
means  that  there  is 
approximately  one  turn  of 
insulation  around  the 
terminal  for  strain  relief. 

Wellp  that  about  "wraps" 
it  up.  ■ 


Fig.  3, 


The     staff     (both     of     us)     at 
ON_LlNE    wish    to    acknowledge 
low  readers  and  advertisers  as  being 
the  true  cause  of  our  successful  first 9 

Our  thanks  and  wishes  for  a 
1  977  full  of  events,  satisfaction  and 


■year, 


peace, 


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SST  T-l  RANDOM  WIRE  ANTENNA  TUNER 

Thu   SST  T-l   Anlnnnu  Tun«r  ecLs 

^^^^^^^^^^^_        y°u    on     HWM°    mn«i    with    a 

random  Itiigih  ttf  w\tr.  In  use  by 
I  hMjh      ^V*  I         3  ma  I  em:  s  for  4  yririt.  See  other  ad 

this  issue.  COD  OK  by  phone: 
<213>  376-5887  or  order  by  mail, 

^^•—         m,  SST     Electronic*.     P.O.     Box     I. 

Uwndilf,  CA  90260. 

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(213)  376-56  87 


If  you  want  a  microcomputer 
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■  8080  MPU  (The  one 
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HAL  Communications  Corp,  has 
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The  MCEM-8080  microcomputer 
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Box  365 P  807  E.  Green  Street,  Urbana,  Illinois  61801 

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All  about 


WHY  YOU  WILL  BE  UNABLE 

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FROM  SUBSCRIBING  TO 

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If  you  can  profit  from  the 
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subscription. 

Kilobyte  will  be  running 
articles  on  every  piece  of  hard- 
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hobbyist  . .  ,  and  reader  reports 
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hardware  (and  software).  You 
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If  you  are  building  a  kit,  for 
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guy.  Pass  along  data  on  how  you 
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, , ,  where  you  got  software  . . , 
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and  be  well  worth  it.  In  case  you 
are  thinking  of  waiting  to  see 
how  Kilobyte  looks,  remember 


that  thousands  of  waiters-to-see 

lost  out  on  the  first  issues  of 
Byte.  Too  bad  ...  the  first  issue 
of  Byte  now  goes  in  some  areas 
for  more  than  the  Charter  sub- 
scription rate! 

This  is  your  chance  to  get  a 
bargain  . . .  please  don't  expect 
the  first  issue  of  Kilobyte  to  be 
in  good  supply. 

HARDWARE  REVIEWS 
IN  KILOBYTE 

In    addition    to    the    letters 

from  readers  explaining  about 
the  problems  they  have  had  with 
hardware  (and  software) ,  plus 
articles  by  readers  on  hardware 
which  they  are  enthusiastic 
about  . . .  Kilobyte  will  be  en- 
couraging the  manufacturers  to 
write  articles  telling  you  the 
details  of  their  equipment  ... 
why  they  used  such  and  such  a 
chip  .  • .  what  it  does  , . .  what 
this  means  to  you  as  the  possible 
user  of  the  system  .  . .  why  the 
bus  was  designed  the  way  it  was 
,  t  ♦  etc,  Manufacturers  are  well 
aware  that  their  articles  will  be 
read  with  skepticism  and  that 
their  credibility  is  on  the  line  ,  . . 
so  we  expect  them  to  be  rela- 
tively candid,  for  in  a  market- 
place such  as  this  one,  with 
many  manufacturers  competing 
very  briskly  for  your  business, 
credibility  is  of  the  utmost 
importance  .  .  .  and  a  loss  of 
credibility  can  well  mean  lost 
business. 

Most  of  the  new  manufac- 
turers of  microcomputer  hard- 
ware are  starting  small,  usually 
with  a  minimum  of  financing  * . , 
so  they  need  your  business  and 
confidence.  You'll  get  to  know 
these  people  through  the  pages 
of  Kilobyte. 

SOFTWARE  PROGRAMS  IN 
KILOBYTE 

In  addition  to  reviews  of  new 
hardware  and  reports  from  the 


readers  on  their  problems,  Kilo- 
byte will  be  making  every  effort 
to  encourage  programmers  to 
send    in    shorter    programs   for 

publication  in  Kilobyte short 

programs,  routines,  algorythms, 
written  for  use  on  hobby 
systems.  It  is  hoped  that  this  will 
eventually  become  a  library 
which  will  be  invaluable  to  you 
when  you  are  writing  programs. 
There  have  been  a  few  programs 
published  elsewhere,  but  these 
have  been  far  too  few. 

Longer  programs  have  a  home 
too.  Kilobyte  will  be  producing 
longer  programs  on  cassette  tape 
for  sale  by  mail  and  via  com- 
puter stores  . . .  complete  with 
documentation.  If  you  have 
some  programs  which  you  think 
might  be  of  value  . . .  and  might 
sell  well  , , ,  get  in  touch  with 
Kilobyte.  The  page  rate  for 
articles  in  Kilobyte  runs  around 
$50  (about  double  that  of  other 
hobby  computer  magazines  the 
last  we  heard),  so  short  programs 
and  routines  could  pay  you  very 
well  if  published.  Longer  pro- 
grams will  be  on  a  royalty  basis 
(15%)  and  the  intention  is  to  sell 
them   at   fairly   low   prices  via 


stores  so  as  to  discourage 
copying  and  theft*  Our  ex- 
perience with  the  73  Morse  Code 
tapes  is  that  if  cassettes  are  made 
available  for  reasonable  prices 
there  is  little  problem  with 
copying. 

KILOBYTE  AIMED 
DIRECTLY  AT  NEWCOMERS 
TO  COMPUTERS 

Most  of  us  are  newcomers, 
one  way  or  another.  Only  bng 
time  dedicated  hobbyists  are 
well  grounded  in  hardware,  soft- 
ware and  systems  , . ,  the  rest  of 
us  may  know  one  or  the  other  of 
these,  but  not  all.  The  intention 
is  to  try  and  keep  a  good  deal  of 
the  material  in  Kilobyte  of  a 
very  fundamental  nature  so  as  to 
bootstrap  newcomers  into  the 
hobby.  This  will  even  include  a 
glossary  page  of  computer  terms 
to  help  the  beginner, 

THE  KILOBYTE 
LABORATORY 

Kilobyte  is  the  ONLY  com- 
puter hobby  magazine  with  its 
own  computer  Sab  set  up.  This 
lab   is   not  a  little  workbench 


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with  an  Aftair  „ . .  it  has  an  8800 
with  floppy  disk,  Imsai,  Wave- 
male,  jolt,  Apple,  Southwest 
Tech,  Sphere,  Ebka,  Intedigent 
Systems,  Astral  2000  . , ,  various 
cassette  systems  such  as  the 
National  Multiplex  ,  .  .  printers 
by  Southwest  Tech,  Teletype, 
Dec,  MPl  ...  terminals  by  Lear, 
Burroughs,    Intelligeni    Systems 

With  this  tab  Kilobyte  is  able 
to  check  out  the  many  systems 
available  to  the  hobbyist  .  • .  to 
interface  I/O  systems  ...  to 
check  memory  and  other  new 
modules and  (most  impor- 
tant) to  check  out  programs 
submitted  to  Kilobyte  for  publi- 
cation or  for  royalty  distribu- 
tion. 

KILOBYTE  TO  SUPPORT 
COMPUTER  STORES 

Older  hobbyists  will  recall 
ihai  publisher  Wayne  Green  pre- 
dicted the  proliferation  of  the 
computer  store  even  before  the 
first  one  was  opened.  Kilobyte 
will  be  available  in  every  com- 
puter store  that  meets  the  Kilo- 
byte requirements  ...  as  will  the 
Kilobyte  program  cassettes. 

In  August  1975  the  very  first 
computer  store  was  opened  (in 
California)  ...  by  August  1976 
there  are  over  50  recognized 
computer  stores  . . .  and  perhaps 
150  one-man  shops  which  hope 
to  grow  into  stores  soon.  Con- 
sidering the  growth  of  the  hobby 
computer  it  will  not  be  sur- 
prising to  many  if  there  are 
about  500  stores  by  August 
1977,..  and  5000  by  1978. 

Since  only  hobbyists  have  the 
wide  background  in  all  phases  of 
computers  to  provide  the  ser- 
vices of  a  computer  store,  a  great 
many  of  the  readers  of  Kilobyte 
will  find  themselves  faced  with 
an  economic  opportunity  of  a 
lifetime  .  ,  .  once  they  are  quali- 
fied. This  is  all  the  more  reason 
for  getting  your  own  computer 
system  .  ,  .  and  reading  Kilobyte. 

KILOBYTE  TO  COST  ARM 
AND  LEG  AT  STORES 

Since  Kilobyte  h  going  to  be 
a  good  deal  better  than  the  other 
hobby  magazines  it  is  only 
reasonable  that  it  should  be  a 
little  more  expensive.  52.00  per 
copy  at  your  stores. 


WHO  IS  BEHIND 
KILOBYTE? 

The  staff  of  73  Magazine  will 
be  putting  Kilobyte  together  .  . . 
it  is  a  staff  of  over  40  people  and 
every  aspect  of  publishing  is 
done  right  at  the  big  73  Maga- 
zine headquarters  building  In 
Peterborough  except  the  actual 
printing  of  the  magazine.  Kilo- 
byte requires  very  large  web 
offset  presses  and  equipment,  so 
it  will  be  printed  in  Columbus, 
Ohio  .  .  *  and  mailed  from  there. 

The  editor,  John  Craig,  has 
been  running  the  I/O  section  of 
73  Magazine  since  last  February 

a  section  of  about  40  pages 

of  hobby  computer  articles  and 
advertising  every  month.  Before 
that  John  was  one  of  the  editors 
of  the  famed  Cabrillo  newsletter. 
John  works  out  of  LompoCj 
California. 

At  the  Kilobyte/73  head- 
quarters the  type  is  set,  articles 
proofread,  pasted  up,  artwork 
prepared,  advertising  sold  and 
prepared  for  publication,  sub- 
scriptions and  readers  service 
handled  by  a  professional  group 
which  has  been  working  together 
for  years.  Add  to  this  the  new 
Prime  computer  system  and  you 
have  a  first  rate  organization. 
Visitors  to  New  Hampshire  are 
invited  to  join  the  thousands  of 
amateur  radio  operators  who 
visit  the  HQ  and  say  hello, 

WHO  IS  THE 
KILOBYTE  PUBLISHER? 

Wayne    Green   is   not  totally 

unknown  in  the  hobby  com* 
puter  field.  It  was  his  frustra- 
tions with  trying  to  get  a  com- 
puter system  to  use  with  73 
Magazine  that  resulted  in  his 
idea  for  Byte  magazine  in  1975. 
In  a  period  of  seven  weeks  Green 
managed  to  find  an  interim 
editor,  get  enough  articles  to  get 
the  magazine  started,  get  mailing 
lists  of  prospective  subscribers, 
write  letters  for  subscriptions, 
get  envelopes  printed,  send  out 
the  subscription  letters  and  get 
in  enough  subscriptions  to  war* 
rant  printing  15,000  copies  of 
the  first  issue  ,  .  .  far  too  few,  it 
turned  out  .  . ,  but  a  lot  more 
than  the  2000  envisioned  at 
first. 

Green's  visit  to  the  micro- 
computer    manufacturers     in 


August  197S  was  reported  in 
detail  in  Byte  and  did  a  lot  to 
help  this  small  new  industry 
grow.   Green    has   followed  this 

1975  visit  up  with  one  in  August 

1976  and  this  will  be  reported  in 
the  first  issue  of  Kilobyte. 

Green  started  publication  of 
7  3  Magazine  in  1960  and 
gradually  built  it  from  a  one 
man  operation  to  the  present 
staff  of  over  40,  73  is  the  fastest 
growing  ham  magazine  . ..  .  over 
30%  increase  during  the  first  six 
months  of  1 976  .  ■  .  and  soon 
will  be  the  largest  in  circulation 
in  the  ham  field.  It  is  already 
more  pages  than  any  others  and 
has  more  advertising. 

Green,  who  is  listed  In  the 
latest  issue  of  Who's  Who,  in 
addition  to  being  the  editor  and 
publisher  of  73,  starting  Byte 
last  year  (no  longer  connected 
with  Byte),  also  is  the  writer  of  a 
nationally  syndicated  newspaper 
column  on  CB  radio. 

MANUFACTURERS  WHO 
CANNOT  ADVERTISE 

The  73  Magazine  policy  of 
not  permitting  firms  to  advertise 
where  there  are  problems  of 
stability,  of  service,  a  question- 
able product,  etc.,  will  be  carried 
on  in  Kilobyte,  Unless  current 
problems  with  Minimieromart, 
Processor  Technology,  E&L 
instruments  and  Ebka  are  re- 
solved you  may  not  be  seeing 
them  in  Kilobyte. 

CAN  YOU  GET  RICH 
VIA  KILOBYTE 

Of  course  you  can!  With  Kilo- 
byte paying  about  double  what 
the  other  hobby  computer  maga- 
zines are  (you  do  want  to  read 
the  best  authors,  don't  you?), 
you  can  parlay  any  field  of 
expertise  of  your  own  into 
enough  money  to  buy  more 
hardware.  Be  sure  that  you 
know  what  you  are  talking 
about  .  .  .  and  that  you  explain 
it  simply,  avoiding  all  the  usual 
buzzwords.  Write  to  Kilobyte, 
Peterborough  NH  03458,  or 
John  Craig,  RED  1G0D,  Lompoc 
CA  93436,  for  instructions  on 
writing  for  Kilobyte  .  . .  it's  easy 
. , ,  and  lucrative. 

COMING  ARTICLES 
Articles  have  been  promised 


for  Kilobyte  by  some  of  the  top 
people  in  the  field  . . .  a  run- 
down on  just  about  everything 
available  „ ,  ,  a  sort  of  super 
buyers'  guide  is  being  prepared 
by  Eric  Stewart  of  Computers 
and  Stuff.  This  will  probably  run 
to  three  parts  to  cover  every- 
thing, Eric  started  with  his  Hrst 
store  in  Provo,  Utah  and  then 
moved  to  the  San  Francisco  area 
.  .  .  he  is  moving  to  a  larger 
building  to  try  and  keep  up  with 
the  business. 

George  Morrow  (Morrow's 
Micro  Stuff)  will  be  writing  on 
cassette  systems  and  interfacing 
...  on  a  fantastically  simple 
prototyping  system  he  uses  . .  . 
Dennis  Brown  (Wavemate)  will 
be  writing  about  the  benefits  of 
wire  wrapping  and  also  give  us 
the  inside  dope  on  how  the 
Wavemate  was  designed  ...  and 
why.  We've  also  been  promised 
good  authoritative  articles  on 
t  he  J  olt  system,  the  new 
Godbout  PACE  computer,  the 
Apple  computer  and  the  Z-80 
CPU  coming  out  by  MITS. 
Marlin  Shelly  of  MPl  (printer) 
has  promised  an  article  on 
parallel  I/O  standards  and  con- 
nectors . . .  George  Tate  of  Com- 
puter Mart  (Orange,  Ca)  will  be 
writing  on  I/O  configurations 
.  . .  Dick  Wilcox,  a  teacher  of 
computer  systems  In  elementary 
schools  will  be  writing  about 
fundamental  software  terms  .  .  * 
monitors,  debuggers,  editors, 
executives,  and  such. 

WHAT  ABOUT  THE 

I/O  SECTION  IN  73? 

This  will  continue,  as  it  has, 
to  bring  fundamental  computer 
info  to  radio  amateurs  through 
the  pages  of  73  ...  as  well  as 
computer  applications  for  ama- 
teurs such  as  pointing  beams  for 
DX  automatically,  reading  Morse 
Code,  etc. 

WHEN  WILL  KILOBYTE 
START? 

The  first  issue  will  be  out  in 
December  1976  ,  ,,  dated  Jan- 
uary 1977.  The  deadline  to  be 
sure  of  getting  this  issue  is 
November  1st  ,  .  T  after  that  you 
may  or  may  not,  depending 
upon  the  demand.  Remember 
what  happened  to  Byte  sub- 
scribers who  waited. 


It  is  widely  believed,  and 
often  written,  that  re- 
flected waves  on  an  rf  trans- 
mission line  represent  power 
flowing  in  the  line  toward  the 
load  and  away  from  the  load. 
Encouraged  for  many  years 
by  the  teaching  of  a 
prestigious  amateur  organiza- 
tion, many  amateurs  take  this 
belief  as  an  article  of  faith. 

But  it  is  not  only  amateurs 
who     so     believe  some 

professionals  do,  also.  They 
construct  ingenious  explana- 
tions of  transmission  line 
phenomena  that  are  based  on 
power  flowing  forward  and 
backward  on  a  transmission 
line  terminated  by  a  load  not 
equal  to  the  characteristic 
impedance  of  the  tine.  They 
devise  equations  containing 
terms  purporting  to  give  the 
magnitude  of  power  flowing 
toward  the  load  and  of  power 
flowing  in  the  reverse  direc- 
tion, and  by  subtracting  one 
from  the  other  get  the  "net 
power"  flowing  into  the  load. 
Never  mind  if  the  "forward 
power' J  is  sometimes  con- 
siderably larger  than  can  be 
accounted  for  by  the  energy 
supplied  by  the  transmitter  in 
unit  time  —  that  is  the  way  it 
must  be,  they  say.  Some  of 
these  professionals  attempt  to 
prove  that  "real  power"  flows 


both  ways  on  the  line,  by 
referring  to  the  readings  of 
so -calked  directional  watt- 
meters, and  overlook  the  un- 
proved and  hidden  assump- 
tions that  their  explanation 
involves. 

In  this  article  I  will 
attempt  to  show  that  power 
cannot  correctly  be  said  to 
flow  in  transmission  lines  in 
any  direction.  I  will  also 
point  out  inherent  fallacies  in 
some  of  the  arguments  pre- 
sented to  support  the  notion 
of  power  being  associated 
with  reflected  waves.  To 
accomplish  these  purposes,  it 
will  be  essential  to  have  a 
clear  understanding  of  the 
basic  definitions  of  energy 
and  of  power,  and  of  the 
differences  between  them.  In 
physics,  energy  is  the  capo* 
bitity  for  doing  work.  A  bent 
spring  possesses  energy;  a 
charge  of  gunpowder 
posSe&Ses  energy;  an  electric 
current  possesses  energy 
because  it  can  run  a  motor,  or 
generate  heat  in  a  resistor,  or 
be  transformed  into  electro- 
magnetic waves  which  then 
do  work.  In  such  cases,  the 
work  done  (or  heat  gen- 
erated, or  electromagnetic 
waves  produced)  is  also 
energy  in  other  forms,  in 
compliance  with  the  laws  of 


Exploding  the 


the  conservation  of  energy. 

Power  is  defined  in  the 
ARRL  Radio  Amateur's 
Handbook  (50th  edition,  p* 
22)  as  the  rate  of  doing  work. 
However,  the  ARRL  now  pre- 
fers (ref.  1 )  a  somewhat 
different  wording,  taken  from 
the  IEEE  Standard  Die* 
tionary  of  Electrical  and  Elec- 
tronic Terms  (1972  edition), 
as  follows:  Power  is  the  time 
rate  of  transferring  or 
transforming  energy.  To 
avoid  any  misunderstanding 
with  the  ARRL  over  the 
correct  definition  of  power,  I 
will  use  the  one  it  prefers,  A 
careful  look  at  this  definition 
shows  clearly  that  the  words 
"transferring"  and  "trans- 
forming"  in  that  definition 
refer  to  energy,  not  to  power. 
The  definition  would  become 
absurd  if  it  were  taken  to 
mean  that  "power  is  the  time 
rate  of  transferring  or  trans- 
forming  power."  Therefore, 
the  thing  that  is  being  trans- 
ferred in  an  electric  circuit  or 
transmission  line  is  energy, 
not  power.  The  thing  being 
transferred,  energy,  is  what 
flows  on  the  line,  and  any 
assumption  that  the  defini- 
tion supports  the  conclusion 
that  power  flows  on  the  line 
is  wholly  unwarranted. 

There    is    another    cogent 


Power  Myth 


-  -  to  set  the  record  straight 


reason  supporting  the  view 
that  power  does  not  flow  in 
transmission  lines.  Power  is  a 

scalar  quantity,  that  is,  a 
quantity  completely  specified 
by  a  number  (of  basic  units, 
such  as  the  Watt)  and  having 
no  direction  in  space,  as  con- 
trasted with  a  vector  quantity 
which  requires  not  only  a 
number  but  also  a  direction 
for  its  complete  specification. 
Because  power  has  no  direc- 
tion, it  cannot  correctly  be 
said  to  flow  in  any  direction 
{ref.  2).  But  what  of  the 
power  quantity  (E)  (I)  {cos 
0)  as  measured  at  the  line 
input?  Does  this  mean  that 
power  is  flowing  in  the  line? 
No,  it  does  not.  It  means  that 
the  flow  of  electric  energy  in 
the  line  is  such  as  to  cause 
work  to  be  done  at  the  rate 
of  (E)  (l)  (cos  &)  at  some 
suitable  place  or  places  in  the 
circuit,  namely  at  one  or 
more  resistive  loads  (ideally, 
only  in  the  equivalent  radia- 
tion resistance  of  the 
antenna). 

I  know  that  it  is  common- 
place to  speak  of  power  as 
flowing  in  rf  and  other 
electric  circuits,  and  such 
informal  speech  often  carries 
a  useful,  if  inexact,  meaning. 
But,  in  dealing  with  the 
rather  complex  phenomena 
on  rf  transmission  lines,  it 
becomes  essential  to  use  such 
terms  as  energy  and  power  in 
accordance  with  their  exact 
meanings. 

Having  discussed  the  basic 
definitions  of  energy  and 
power  and  their  significance, 
we  can  now  examine  some  of 
the  fallacies  offered  In 
support  of  the  conclusion 
that  reflected  waves  on  a 
transmission  line  represent  or 
contain  power  flowing  in  two 
directions. 

T  An  equation  has  been 
published  (ref.  3)  in  the  fol- 
lowing form: 


IE+J2        (El2 


Zc 


Zc 


=  "Net  Power  Fiow" 


Hubert  Woods  W9IK/XEIZX 
Calic  LasNubes  1760 
Guadalajara  5 
Jalisco,  Mexico 


in  which,  to  use  the  author's 
words,  "the  first  term  to  the 
right  of  the  P  expresses  the 
power  associated  with  the 
incident  wave,  and  the  second 
term,   the    reflected    power/' 


120 


This  equation  treats  power  as 
if  it  were  a  vector  quantity;  it 
clearly  implies,  as  do  the 
author's  words,  that  power 
flows  both  ways  on  the  line 
simultaneously,  and  that 
power  flowing  one  way  can 
cancel,  partially  or  wholly, 
the  power  flowing  the  other 
way.  All  of  this  is  in  direct 
conflict  with  the  fundamental 
definition  and  meaning  of 
power,  as  previously 
discussed. 

2.  It  is  sometimes  claimed 
that  the  readings  of  "direc- 
tional wattmeters*'  prove  that 
power  flows  both  ways  on 
the  line,  thus  representing 
power  associated  with  the 
incident  and  reflected  waves 
(ref\  4}*  These  instruments 
are  actuated  by  samples  of 
the  line  current  and  line 
voltage  (ref.  5),  There  is  no 
uncertainty  about  the  deriva- 
tion of  these  meter  readings. 
However,  endowing  these 
readings  with  meaning  with 
respect  to  power  in  the 
incident  and  reflected  waves 
requires     two     assumptions: 


first,  that  the  incident  and 
reflected  waves  have  a 
physical  existence  on  the  line; 
and  second,  that  they 
represent  power  flowing  on 
the  line.  Neither  of  these 
assumptions  is  automatically 
shown  to  be  correct  by  the 
meter  readings  themselves, 
which,  as  stated,  are  actuated 
by  line  current  and  line 
voltage,  and  which  would 
continue  to  be  the  same  read- 
ings obtained  from  the  same 
line  current  and  line  voltage 
with  the  same  phase  angle 
even  if  the  incident  and 
reflected  waves  had  no 
physical  existence  on  the  line. 
Thus  the  "directional  watt- 
meter11 readings  do  not  prove 
that  there  is  any  power  asso- 
ciated with  these  waves,  or,  in 
fact,  that  these  waves  have 
any  physical  existence. 

3.  When  the  line  and  load 
are  considerably  mismatched, 
the  "directional  wattmeter" 
indicates  a  much  larger  for- 
ward power  {it  is  said)  than 
can  be  accounted  for  by  the 
energy  output  capability  of 


the  transmitter.  This  has  been 
said  to  be  "a  normal  condi- 
tion which  must  exist  in 
order  for  a  mismatched  load 
to  absorb  all  the  power 
delivered  by  the  source,  while 
at  the  same  time  reflecting  a 
percentage  of  the  total  power 
it  receives"  (ref.  6).  But  as 
power  is  the  time  rate  of 
transferring  or  transforming 
energy,  how  could  the  time 
rate  of  transferring  or  trans- 
forming energy  anywhere  on 
the  line  be  greater  than  the 
energy  put  into  it  in  unit 
time?  This  would  be  manu- 
facturing energy  out  of 
nothing! 

In  summary,  I  have  shown, 
I  hope,  by  recourse  to  basic 
definitions  and  their 
meanings,  that  power  does 
not  flow  in  transmission  lines 
or  other  electric  circuits.  I 
feel  that  there  have  been 
errors  in  some  of  the  state- 
ments that  have  been  pub- 
lished in  support  of  the  con- 
trary view.  It  must  therefore 
be  concluded  that  reflected 
waves  do  not  represent  power 


flowing  in  a  transmission  line, 
in  any  direction.  Let  us  hope 
that  professionals  (and  ama- 
teurs, too)  will  take  seriously 
the  basic  definitions  of  the 
terms  they  use  so  frequently. 
I  confess  that  I  have  not 
always  done  so.  ■ 

References 

1.  Personal  letter  from  the 
ARRL,  dated  Jan.  29,  1974. 

2.  Personal  letter  from  Dr, 
Chester  H.  Page,  SI  Units  Coor- 
dinator, National  Bureau  of  Stan- 
dards, dated  May  3,  1974.  Dr. 
Page  is  also  Chief,  Electricity 
Division,  Institute  for  Basic  Stan- 
dards, National  Bureau  of  Stan- 
dards. In  view  of  the  high  positron 
Dr.  Page  holds  in  the  field  of 
electrical  definitions  and  their 
meanings,  I  quote,  with  his  per- 
mission, the  following  sentence 
from  his  letter:  "'You  are  correct; 
power  does  not  flow  —  energy 
flows." 

3.  Maxwell,  M.  Waller,  "Another 
Look  At  Reflections/'  Part  3, 
QST,  Aug.,  1973,  p.  43. 

4.  fbid*r  p.  42, 

5.  DeMaw,  Doug,  "In-Line  RF 
Power  Metering,"  QSTr  Dec, 
1969,  p,  11. 

6.  Maxwell,  M.  Walter,  "Another 
Look  at  Reflections;"  Part  4, 
QST,  Oct,,  1973,  p.  22. 


REPORT 


from  page  74 

have  any   nifty  software  control   of 
starting  and  stopping  the  tape. 

The  manual  provided  with  the 
reader  is  excellent.  It  includes  the 
theory  of  operation,  construction  (if 
you  buy  Ft  in  kit  form  J,  parts  list, 
interfacing  instructions,  schematic, 
board  layout,  and  most  importantly, 
an  6080  program  listing  for  bootstrap- 


ping  programs  in  from  the  reader. 

Interfacing  the  OP-80A  is  a  breeze. 
The  diagram  of  the  I/O  socket  shown 
here  illustrates  the  interface  signals. 
These  include  the  eight  data  tines,  an 
acknowledge  and  a  ready  line  (the  SI 
and  S2  status  inputs  are  optional  and 
can  be  whatever  you  desire).  The 
"data  ready"  (or  Reader  Data  Avail 
able]  is  generated  from  the  sprocket 
hole  and  the  acknowledge  signal  must 
be  generated  by  either  hardware  or 
software  from  the  computer.  (We 
interfaced  the  OP -80 A  to  our  Varian 
V-73  and  its  paper  tape  controller  was 
kind  enough  to  provide  us  with  an 
acknowledge  signal  For  an  8 060 
based  system,  an  output  port  would 
be  used  to  provide  this  signal  through 
software.) 

One  item  which  is  missing  from  the 
"posed"  photograph  is  a  small  high- 
intensity  lamp  {using  a  12  volt  auto 
lamp)  which  is  placed  directly  over 
the  read  station.  The  light  intensity 
"alignment"  procedure  is  simply  a 
matter  of  placing  the  light  over  the 
read  station  until  the  SP  (sprocket) 
LED  comes  on. 

The  OP  80A  is  available  from  Oliver 
Audio  Engineering,  7330  Laurel 
Canyon  Btvd.,  North  Hollywood  CA 
91605.  The  price  is  $74.50  in  kit  form 
or  $95.00  assembled  and  tested  (add 
S2.50  for  shipping  and  handling),  A 
lamp  kit  option  is  also  available  at 
£19.95  and  a  tape  transport  unit  will 
be  available  in  the  future  (for  you  lazy 
types!. 


121 


The  graveyard  of 
abandoned  match!  ts. 


F.  G.  Rayer  G3QGR 
Longdon  Heath 
Up  tan-on-Severn 
Wares.  WHS  OR  J 
England 


Exploding  the  SWR  Myth 

-  -  to  set  the  record  straighter 


As  a  regular  user  for 
years  of  end  feci 
antennas,  I  have  felt  there 
should  be  some  correct 
length,  and  some  ideal  or  best 
way  to  tune  the  antenna  and 
couple  it  to  the  transmitter. 
The  latter  item  -  the  fabu- 
lous matchit  would  peak 
up  transmitted  signal  strength 
very  well,  rather  like  tuning  a 
receiver  pre-selector  when 
receiving.  (Admittedly  a 
flatter  response  was  expected, 
due  to  lower  Q.) 

Signal  strength  reports 
from  contacts  did  not  con- 
firm this,  nor  did  a  remote 
pickup  antenna,  with  diode 
and  indicating  meter.  So  tests 
were  made  to  try  to  discover 
if  the  fabulous  rnatchit 
existed,  and  to  find  it  if  it 
di 


As  it  had  been  amply 
demonstrated  that  an  rf 
ammeter  in  the  antenna  lead 
gave  maximum  reading  for 
maximum  radiated  signal,  if 
operating  frequency  and  the 
whole  antenna-ground  system 
remained  unchanged,  such  a 
meter  was  used  as  the  indi- 
cating instrument. 


The  Beginning 

Putting  the  antenna 
directly  on  the  Tx,  Fig.  1  (a) 
was  the  start.  PA  tuning  and 
loading  controls  were  far 
from  their  usual  settings  with 
the  PA  dipped,  but  PA  grid 
and  anode  currents  were 
noted,  and  also  antenna 
current. 

The  roller-coil  favorite 
matchit    B    was    then    intro- 


duced, set  to  its  usual  values. 
Complete  readjustment  of  PA 
tuning  was  needed.  Loading 
was  set  to  get  the  same  plate 
current  as  before.  Hey  ho, 
antenna  current  was  exactly 
ihe  same.  Nor  was  any 
improvement  possible,  with 
changes  to  L  and  C,  followed 
by  PA  re-tuning. 

Never  mind:  Parallel 
tuning  of  this  antenna  length 
had  often  been  used,  so  Fig. 
2(a)  was  substituted.  With 
customary  adjustment  of  this 
parallel  matchit,  current 
shown  fay  the  rf  meter  was 
exactly  as  before.  So  both  L 
and  C  were  grossly  changed 
from  their  "correct"  values 
for  the  band,  and  tap  T  was 
moved  to  unusual  positions. 
Provided  it  was  still  possible 


to  load  the  PA  to  the  noted 
input,  antenna  current  was 
the  same  with  all  changes 
made. 


Oh,  Dear! 

An  excellent  matchit  well 
known  for  its  ability  to  pro- 
vide 1:1  swr  on  coax  from 
the  Tx  was  substituted,  as 
shown  in  Fig.  2(b}.  With  the 
swr  at  1:1,  antenna  current 
stood  at  exactly  the  same 
figure  as  before.  With  the 
excellent  matchit  mistuned, 
5:1  on  the  swr  and  PA 
dipped,  antenna  current  was 
exactly  the  same. 

Perhaps  the  antenna  length 
was  responsible?  It  was  cut  to 
length  by  the  book,  and  was 
possibly  humming  with 
resonant  energy? 


122 


w 


w 


^7  Fig,  2  Two  parallel-timed 

circuits, 


Tx 


m 


A 


B 


Fig,  L  Direct  connection  and  roller  coaster  matcher. 


No,  changes  to  its  length 
naturally  altered  the  rf 
current,  but  starting  again 
from  Fig,  1(a),  ail  remained 
the  same. 

Conclusion 

Provided  the  PA  can  be 
loaded  and  dipped,  any 
matchit,  or  indeed  none  at 
ait,  will  give  exactly  the  same 


signal  strength.  So  what  our 

favorite  matchit  does  to 
justify  its  shelf  space  comes 
under  other  headings  —  it  can 
bring  an  otherwise  impossible 
antenna  impedance  within 
the  range  of  the  transmitter, 
it  can  let  the  Tx  see  a  line 
with  a  low  swrt  if  the  Tx  or  a 
filter  needs  that,  and  it  can  be 
unfavorable     to     harmonics 


(especially  Fig,  2}.  But  appar- 
ently It  will  never  change  you 
from  S5  to  S9  plus,  or  indeed 
from  S5  to  56.  ■ 


/77 


B 


BONANZA 


PRICES  WER*. 


100%  pretested  &  guaranteed  good 


PMT  NO 


vtmo 


IMJKHH 


jmou. 


mwL_ 


Output  V  2  37  Ml 
Input  V.  10  Mjji 

Output  I  150  mt 
Cfumrc  Pkg. 


Output  V  5  Ph. 
Inpul  V.  35  Mai. 
Output  I  I  Amp 


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Input  V  35  Mu 
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Input  t  15  Max 
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123 


NEW! 
FM144-10SXR 


FM 144-1 OSXR-11 


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Price  subject  to  change  without  nonce 

Regulated  AC /PS 
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AIRCRAFT  TYPE  FREQUENCY  SELECTOR:  Large  and 
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equipment 

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FULLY  REGULATED  INTEGRAL  POWER  SUPPLIES: 
Operating  voltage  for  all  circuits,  i.e..  I2v,  9v  and 
5v  have  independently  regulated  supplies  12v  regti 
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out  and  protects  final  transistor  from  overload 


-MONITOR  LAMPS:  2  LED  S  on  front  panel  indicate 
(1)  incoming  signal  channel  busy,  and  (2)  unlock 
condition  of  phase  locked  loop 

•  DUPLEX  FREQUENCY  OFFSET:  600KH;  plus  or  minus 
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unitized  modules  eliminate  stray  coupling  and  facih 
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•  ACCESSORY  SOCKET:  Fully  wired  for  touch-tone 
phone  patch,  and  other  accessories 

•RECEIVE:  25  uv  sensitivity.  15  pole  filter  as  well  as 
monolithic  crystal  filter  and  automatic  tuned  LC 
circuits  provide  superior  skirt  selectivity 

•AUDIO  OUTPUT:  4 WATTS 

•  HIGH/LOW  POWER  OUTPUT:  15  watts  and  1  watt, 
switch  selected  Low  power  may  be  adjusted 
anywhere  between  1  watt  and  15  watts 

•  PRIORITY  CHANNEL:  Instant  selection  by  front  panel 
switch,  Diode  matrix  may  be  owner  re  programmed 
to  any  frequency  (146.52  provided) 

•  DUAL  METER:  Provides  MS"  reading  on  receive  and 
power  out  on  transmit 

■  OTHER  FEATURES: 
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All  cords,  plugs,  fuses,  mobile  mount,  microphone 
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8817  3.W.  129th  Terrace,  Miami,  Florida  33176 
Telephone  (305)  233-3631 

U.S.  DISTRIBUTOR  PLEASE  WRITE  FOR  FURTHER  INFORMATION 


WESTERN  REGIONAL  SALES 

&  SERVICE  CENTER 

CONSUMER  COMMUNICATIONS,  INC 

611S-15TH  AVE    N.W 

SEATTLE.  WA  93107 

TELEPHONE  (206)  7#4-7337 


124 


Robert  L.  Fischer  WB8BEL 
599  Sherwood  Drive 
Huntington    WV  25704 


\ 


SB-ilQA 

HE  AW  HONE 
.  JACK 


g  a  Dead  Band  to  Life 


beacon  CQer 


tape     y 

PLAYER 

EARPHONE 

JACK 


■^  sb-ho  a 

PHONE 
PATCH 
JACK 


EAHPHOKE  CEMChfTEO 
TO  TELEPHONE  PltK-iiP  COtL 


Fig,  L  Grcut  try  used  to  oper- 
ate Heath  SB-1IOA  trans- 
ceiver  as  a  beacon  station. 


This  revolutionary  new 
concept  in  repeater 
design  centers  around  an  end- 
less loop  cassette  cartridge.  A 
thirty  second  CO  with  calling 
instructions  was  recorded  on 
a  ninety  second  endless  loop. 
As  the  loop  runs  through  a 
tape  player,  one  hears  the  CQ 
followed  by  a  minute  of 
silence.  When  the  player  out- 
put is  patched  into  a  trans- 
ceiver VOX  circuit,  the  result 
is  instant  beacon.  A  word  of 


caution  on  the  patch:  The  dc 
component  of  the  tape  player 
output  should  be  isolated 
from  the  VOX  input  to  pre- 
vent nuisance  tripping. 

The  only  disadvantage  I 
found  with  this  simple 
arrangement  is  that  it  requires 
constant  attendance  at  the 
transceiver.  There  are  many 
times  when  I  would  prefer  to 
listen  for  calls  in  my  family 
room  with  the  rest  of  the 
family.  An  extension  speaker 


was  easily  added,  but  the  wife 
would  absolutely  not  con- 
done the  no-signal  noise  of 
the  receiver.  Obviously,  a 
squelch  circuit  was  in  order- 
On  the  other  hand,  I  had  no 
desire  to  mutilate  the  trans- 
ceiver or  decrease  its  sensi- 
tivity. 

An  interesting  problem 
indeed  —  how  can  the  noise 
be  squelched  with  minimum 
circuit  disturbance?  Low 
voltage  zener  diodes  filled  the 


bill*  Two  diodes,  back  to 
back  in  series  with  the 
speaker,  will  conduct  only 
when  their  zener  voltages  are 
exceeded.  Audio  output 
level  is  adjusted  so  that  the 
noise  level  is  just  below  zener 
breakdown  voltage.  A  SPST 
switch  was  added  to  short  out 
the  zeners  for  weak  signal 
work, 

I  realize  that  this  crude 
design  could  use  some  refine- 
ment, but  I  leave  that  to  the 
perfectionists  in  our  midst, » 


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S817  S  w  i29iti  Terrace,  Miami.  Florida  33176 

COURTEOUS  PERSONAL  SERVICE -SAME  DAY  SHIPMENT  *  Pricw  *ub|«Ct  to  Changs  without  notice. 
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ItMiHiiCM 


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F/#.  2  Charger 


Dave  Faucher  WA1UQC 
25  Freedom  Drive 
CotlmsviUe  CT  06022 


The  \C-J1  Walkie 


-  -  portabilization  with  nicads 


It  all  started  with  a  desire 
to  have  a  multi-channel, 
top  quality  performance, 
portable  transceiver  that  I 
could  carry  with  me  on  field 
trips,  CD  activities,  repeater 
maintenance  or  just  about 
any  where* 

Looking  at  the  problem 
from  several  different  angles, 
I  immediately  saw  that  the 
cost  of  a  new  HT  was  just 
about  out  of  the  question. 
External  battery  packs  are 
usually  cumbersome  and 
heavy  —  even  messy,  I 
popped    the   covers   off   my 


I  COM  IC-22A  and  to  my  sur- 
prise there  was  plenty  of 
room  for  an  internal  nicad 
battery  pack.  In  fitting  the 
batteries  inside,  I  wanted  to 
make  the  fewest  possible 
outside  modifications  to  the 
rig,  so  as  not  to  detract  from 
its  clean-cut  design. 

The  first  step  in  this  modi- 
fication is  to  turn  off  the 
light  bulbs.  Next,  insure  that 
the  normal  external  power 
source  and  the  internal  nicad 
pack  are  not  paralleled 
together.  I  mounted  a  minia- 
ture DPDT  toggle  switch  on 


the  rear  panel  to  accomplish 
this  objective,  I  needed  a 
battery  charger  input,  so  I 
connected  the  positive  side  of 
the  nicads  to  pin  3  of  the  9 
pin  accessory  socket;  pin  8  is 
negative  ground. 

Before  installing  the 
batteries,  I  decided  it  would 
be  best  to  eliminate  the  possi- 
bility of  the  batteries  rubbing 
against  the  bottom  of  the 
PCBA  solder  etchings,  so  I 
placed  a  piece  of  heavy  gauge 
clear  flexible  plastic  over  the 
PCBA  etch  side. 

Due  to  the  voltage  require- 


Empty  space  available. 


Batteries  installed. 


126 


ment  for  optimum  perfor- 
mance of  the  IC-22A,  I 
hooked  up  eleven  A  A  nicad 
cells  in  series,  making  a  13,75 
V  dc  battery  source.  Current 
drain  with  the  lights  off  is 
approximately  40  mA 
standby,  85  mA  RCV,  and 
550  mA  transmit  in  the  1 
Watt  position.  If  you  choose 
to  replace  the  speaker  with  a 
smaller  onef  you  could  fit  in 
two  plastic  6  pack  battery 
holders.  But  if  you  do  as  I 
did,  and  leave  the  original 
speaker  in,  you  need  one  4 


Flexible  plastic  protective 
covering. 

pack,  one  3  pack  and  two 
double  pack  battery  holders. 
It  is  not  as  neat  looking,  but 
it  does  fit  without  changing 
the  original  speaker. 

For  a  nice  finishing  touch 
you  might  make  up  some- 
thing sharp,  like  a  black 
leather  suede  carrying  case 
with  a  shoulder  strap.  Then 
hook  up  a  rubber  duckie  with 
a  right  angle  connector,  and 
away  you  go.  ■ 


Same  day  shipment 
First  l«ne  parts  only  factory 
tested  Guaranteed  money 
back,  Quality  iC's  and  other 
components  at  'actor y  prices 

INTEGRATED  CIRCUITS 


MWTL 

UMftW 

V 

WVBX 

if 

BUWN 

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M741W 

17 

^Titm 

41 

m*m 

J* 

P.O.  Box  4430M  Santa  Clara,  CA  95054 

(408)  988-1640 

S5.00  min,  order  U.S.  funds 

Calif,  residents  add  6%  tax. 

FREE:  Send  for  your  copy  of 

our  1976  QUEST  CATALOG, 

Include 
.13* 
stamp. 


VCifl 

ELECTRONICS 


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Limited  quanriiies  available 
For  posiage  add  S2  00 
Foreiqn  Sfi  00 


Miles  Per  Gallon 
Circuit 

ral  f  fcwv  Sensor      $29  50 
Speed  Transducer      £  Q.0Q 

(Specify  car  make  ana  year ) 
CMOS  Rale  Multipliers  $19.95 
2-  .50  in  Displays       £  2  50 
Includes  OfCuH  Oescriptifn, 
PC  Board  rol  included. 


talk 

power 
by 


-L 


Quality  for  an  Economy  Price 
Solid  State  Construction 

Linear  Switch  (FM/SSB) 
Broad  Band 


Model     Input       Output 

Typical 

Frequency 

Price 

f02       10W*2f>W  50W-90W 

10Wrn/?0wout 

143-149MN1 

£139.00 

702B     1W-   5W     60W-80W 

1Wrn/70Woul 

143  149MHz 

S15900 

Now    gel    TPL    COMMUNICATIONS    quality    and 

reliability  at  an  economy  price.  The  solid  state  construe - 

>n.  featuring  magnetically  coupled  transistors  and  a 

Moating  ground,  gives  you  an  electron ioally  protected 

amplifier  that  should  last  and  last, 

The  Linear  Bias  Switch  allows  you  to  operate  on  either 
FM  or  SSB  The  702  and  702B  are  exceptionally  well 
suited  for  2-meter  SSB  Typical  power  output  levels  as 
rugh  as  tOOW  PEP  can  be  achieved  with  the  proper  drive. 

The  broad  band  frequency  range  means  that  your 
amplifier  is  immediately  ready  to  use..  No  tuning  is 
required  for  the  entire  2- meter  band  and  adjacent  MARS 
channels  on  TPL  s  new  Sacm-o-line, . 

See  these  greal  new  additions  to  the  TPL  COM- 
MUNICATIONS product  line  at  your  favorite  radto  dealer. 

Calt  or  wrrfe  for  prices  and  tntor- 
mation  on  TPL's  complete  fine  of 
amateur  and  commercial  amplifiers 

COMMUNICATIONS  INC 

132i  VT  135TH  ST.,  GARDENA,  CA  90247  *(21  3)  530.9814 

Con  ado:  A  ,C .  Si  mmenda  &  Sons  Ltd*,  26S  York  land  Blvd.,  Willowdolfj  0marioM2J  1 S9 
Export  :  EtAEC  Inc.,  2350  South  30th  A^uc,  HolJaidole,  Fla,  33009 


PSEUDO 
VESTIGIAL 

SIDEBAND 
FILTER 


15  WATT  FSTV  TRAWSIMlTTE^ 

audio  modulation 


F&ST SCAN 
H'POWep 

UNBAR 


127 


FILTERS 


ELIMINATE  INTERFERENCE  TO  TV  SETS  WITH 
AMECO  HIGH  AND  LOW  PASS  FILTERS 

LOW  PASS  FILTER 

MODEL  IN  2 

The  Aineco  low  pass  filter 

suppresses     the     radiation 

of    all    spurious     signals 

above  40  Me.  If  is  designed 

lot  Coaxial  cable   (52  to 

72  ohms).  Orher  features  include:  Negligible  Insertion 

LosSj    35   db.  and   more   attenuation  of   harmonic  and 

spurious  frequencies  above  50  MC,  wifl  hondfe  up  to 

200  watts  of  RF  power. 

Model  LN  2  $4.95 

LOW  COST 

HIGH-PASS  FILTER 

MODEL  H!M5 

Model  HP-45  ii  a  single  section  hjgh-pass  filler.  All 
frequencies  above  45  MC,  are  passed  through  Without 
foss.  Other  features  mcEude:  40  dbr  and  more  attenua- 
tion al  14  MC.  and  below;  20  db.  attenuation  at  10 
meters.  Negligible  insertion  foss.  $1.95 

MOBILE  COMMUNICATIONS  FILTERS  FOR  VEHICULAR 
AND  MARINE  ELECTRICAL  SYSTEMS 

AF-104  Alternator   Filter,    non-tunable  $  4.90 

C-20  Feed-thru  Coax  Filter.   .1    mf  2.58 

C-40  Feed-thru  Coax  Filter,  .5  mf  4;0a 

C  70  Same  as  C-40,  except  70  amps.  478 

Ce  330  Generator  Filter,  3-30  MHz,  Hf  amp.  4.90 

G-23  Marine  Generator  Filler,  Tunable  7.64 

HF-3040  Generator  Filter,   Hi-amp,,   30  oO  MHz  4.90 

T-52  Tunable  Alt.  Filter,  52A,  22-60  MH*  12.59 

T-70  Tunable  Alt,  Filter,  70A,  22-60  MHz  13,7 4 

TH-70  Tunable  Alt.  Fitter,  70A,   100-200  MHi  13 J 4 

TM-49  Tunable  Marine  Alternator  Filter,  49A  13.14 

TM6S  Tunable  Marine  Alternator  Filter,  68 A  13.69 

VF  225  Voltage  Regulator  Fifter  4.90 


CES  Touch  Tone 
Pads  —  $49.95  ea. 
•  Model  200  - 
acoustic  coup- 
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for  mounting  on 
Wa  Ikies  or  hand- 
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11&988 

£8©sa 

fiS  ESQ 
OSB 


MODEL 

200 


MODEL 
210 


CES  Model  220 
CES  can  now  offer 
you  a  TOUCH- 
TONE*  back  for 
Standard  Communi- 
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radios.  This  is  the 
com  p  lete  back 
assembly  with  the 
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encoder  mounted 
and  ready  to  plug 
into  the  private 
channel  connector. 
Also  included  is  an 
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and  an  external  tone 
deviation  adjust- 
ment. 

Check  our 
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PQ.  4. 


Name 


SUNKYI«^ 

A  LOT  of  antenna  in  3  LITTLE  space, 

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radiates  a  good  tignd  it  1  /TO  wavelength  long!  * 


o  npo 

S.-*>Dil 


o 


\m  HC-D 


•patent  N&,  JA5&J2Q 

NG  I  PHWtCTlff  Till 


Sd — 


0 

ex 


* !■■. nM  support 


fit?  "qp  fifi 


scrier  suppufd 

— — i-TUH  Viki  WLM  (OIL 


o 


Ffl»   ruKIKC,  iDJUil 

r  e  PAiiric  d  TL*«i 


Sft.DE!  {DM   ID   I3ILL 


D 


NKBU*4S  i»SuuW   Mi 


JlH  LNE  *  ti 


I 


•  This  e(«trlC8!ly  small  flD/ 75,  40.  &  20  melar  antenna  operates 
atanyleng1hfrQfn24to7Qleet  *  roetftra  baton  or  trans  match 
needed  ■  portable— erects  £  stores  in  minutes  ■  small 
enough  tq  tit  manic  or  apart  mtm  *  full  legal  power  *  lewSWR 
over  complete  SO/  75 ,40r*  20  meter  bands  *  much  lower  atmo- 
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includes  a  pair  ot  specially ^made  4-inch  dia.  by  4-inch  long 
carta,  cental nirtg  336  feet  of  radiated  conductor,  baton,  50  ft 
RG58/Ucoax,  PL253  connector,  nylon  rope  t  instruction  man- 
ual •  now  in  use  by  US  Dept.  of  Slate.  US  Army,  radio  schools . 
plus  thousands  ol  hams  |he  world  over 


SST  T-l  RANDOM  WIRE  ANTENNA  TUNER 

All     band      oiwmian     (160-10 

:tiL'C.(>rs>  with  mn st  *nv  rjnrioni 
length  wire.  £00  wmlt  power  r-jip- 
aSjiiity.  Ideal  for  pcnrlatilp  or  ttvinr 
operniHm.  A  nioal  iot  Field  Day. 
Swtt:  2*41/4x2  .1.-R.  WuLll-tn 
neon  tiuiu-up  inciii'jtNir.  Guaxaal- 
iped  for  SOdjtVS,  Compact  •■  ru*y 
to  u&*  OnLv  $Uft.-9S  Postpaid  iudd 
galea  Hi  in  CA> 

SST  Electronics,  PO  Box  1,  Lawndale  CA  90260 

(213)  376-5887 


talk 

power 

by 


tor  an  Economy  Pri 
THAT'S  RIGHT  ! 
introducing  the  EC0N0-UNE 


Model    In  pur 

702      5.20W 
70?6  I-4W 

Ou  P  pu  F 

S0.90W 

60-flOW 

Typical: 
lOin   70ou* 

1    in    70  out 

Frequency 

143*149  MHt 
143- U?  MHi 

Price 

SI  39,00 

1169,00 

Now  get  TPL  COMMUNICATIONS  quality  and 
reliability  al  an  economy  price.  The  new  Econo- 
Lme  gives  you  everything,  that  you've  come  to 
expeel  1rom  TPL  al  a  real  cost  reduction.  The 
3atest  mechanical  and  electronic  construction 
techniques  combine  to  make  the  Econo-Line 
your  oesi  amplifier  value,  Unique  broad-band 
circuitry  requires  no  tuning  th rough out  the 
entire  2-Meter  band  and  adjacent  MARS  cnan- 
nels.  See  These  great  new  additions  to  iheTPL 
COMMUNICATIONS  produc)  line  at  your  Favorite 
amateur  radio  dealer. 

For  prices  and  specifications  pfease  write 
for  our  Amateur  Products  Summary! 
FCC  type  accepted  power  amplifiers  also 
available.  Please  call  or  write  for  a  copy 
of  TPL's  Commercial  Products  Sum- 
mary. 


an 


Address 


JAMPHENOL 


SERIES  »S1  -  PACKAGED 
CA6LE  ASSEMBLES 
All  popular  lengths  are  now  available  in 
your  choice  of  RG  8/U  or  RG  58/11  type 
low  loss  poly  foam  dielectric  cable.  Installed 
PL-259  connectors  are  ASTROplated®  — 
Amphenol's  new  non-tarnishing  finish  — 
which  has  all  the  advantages  oi  precious 
metal  plus  more  heat,  corrosion  and  abra- 
sion resistors  that  silver  ever  had! 

RG  58/U  TYPE  POLYFOAM  COAXIAL 
CABLE  ASSEMBLIES 
581-5803:       3-ft.      with      ASTROplated 
PL-259's  on  both  ends,    T  .  . 
5  81-5812:       1  2-ft-      with 
PL-259's  on  both  ends.    .  .  . 
5  81-5820-2:      20-ft.      with 
PL-259's  on  both  ends,    .  .  . 
581-58  50:       50-ft.      with 
PL-259's  on  both  ends.    ... 
5  81  -5  8  7  5  :       7  5-ft.      with 


.....$  o.82 
ASTROplated 

.  .  .  .  ,  S  5.08 
ASTROplated 

5>    5  r  88 

ASTROplated 

.,,-.  ...,:f  8.94 
ASTROplated 


PL-259'son  both  ends.    . $11.22 

581-58100:       100-ft.     with      ASTROplated 
PL-259Js  on  both  ends $12,98 

RG  8/U  TYPE  POLYFOAM  COAXIAL 

CABLE  ASSEMBLIES 

581-803:    3-ft.  with  ASTROplated  PL-259Ts 

on  both  ends.  .  .,.*  +  •*»*<.  *  \  *  * '.' .  t  $   4.46 

581-820:       20-ft.      with      ASTROplated 

PL-259's  on  both  ends.    t  , $10.36 

581-850;  50-ft.  with 
PL-259's  on  both  ends.  .  .  , 
581-875:  75-ft.  with 
PL-259^s  on  both  ends,  .  .  . 
5  81-8100:  100-ft.  with 
PL*259*s  on  both  ends.    .  .  - 


ASTROplated 
.,,«»*  $1 8,58 
ASTROplated 

■     ■     ■     ■     i     il    ip  mO.  TO 

ASTROplated 
......  $31.96 


ALL  BAND  PREAMPLIFIERS 

■fi  THRU  160  METERS 
■  TWO  MODUS  AVAILABLE 
•  RECOMMEND  ED  f  OR 
RECEIVED  USE  ONtY 

'  INCLUDES  P  OWE  ft  SUPPLY 

MODEL  PLF  employs  a  dual  gate  FET  providing  noise 
figures  of  1.5  lo  3.4  db,,  depending  upon  the  band* 
The  weak  sSgnql  performance  of  most  receivers  as  well 
as  image  and  spurious  refection  are  greatly  improved. 
Overall  gain  is  in  excess  of  30  db.  Panel  contains 
switching  that  transfers  the  antenna  dfrectly  to  the  re- 
ceiver or  to  the  Preamp. 

Model  PLF  1  T7V  AC,  60  Hi.  Wired  &  Tested         $44,00 

MODEL  PC  LP  is  identical  En  all  respects  to  the  PLF  ex- 
cept that  two  nu vigors  are  used  instead  of  the  FET. 
Mocfel  PCLP  H7V  AC,  60  Hz.  Wired  &  tested        $39,00 

UHF  RF  CONNECTORS 

A  ^  C  D  E 

Low  loss  R-F  connector*  for  Amateurs,  CitLzens  Band 
and  laboratory  use.  Silver  plated  tor  high  RF  conduc- 
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PL-259  Coaxial  Plug   S  ,80 

SG-239  Coaxial  Receptacle 68 

M-359  Coaxial  Right  Angle  Adapter    .,    i:i() 

PL-25S  CoaxUI  junction 


A 
B 
C 
D 
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t  + ,  ,  f     1 ,31 

UG175/U    Adapter  for  RG-5S/U  .  .  ! 25 

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master  ofisrg? 


City 


State 


Radio  Electronics 

386  Main  Street 

Medford  MA  02155 

(617)395-8280 

New  England's 
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Order: 


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BankAmericard 
accepted 


Prices  FOB  Medford  MA. 
All  units  can  be  shipped 
UPS.  Mass,  residents  add 
5%  sales  tax.  Orders  over 
$1000  deduct  5%.  Add  $2 
for  shipping  &  handling  on 
all  orders. 


i_ 


j 


128 


6  METER  BEAMS 


3.5*6-10   ELEMENTS 

Prav«n  performance  from  ragged.  Ml  ilte.  6  meter  beams  * 
Element  Kpairtn^A  and  length*  hav*  bren  rare-fulty  eitgineerrd  to 
five  brat  pattern,  high  for**rd  gain,  food  fn*tl  to  back  mio 
and  brtaul  frvquvney  response. 

Boosa  an  .^*  -all  and  element*  are  a/4"  -  S/t"  .043  wail 
aeajnleaa  chrome  fitusb  aluminum  rufauig.  The  3  and  5  cteraeni 
beam*  lave  I  -II  f'bwmi.  Ttt4r*BJid  IQelemexit  twarna 

bate  1  ■»■■•*'*  -  t  1/2"'  ijoonu.  All  brack***  *r*  bravv  gauge 
farmed  ilutruniim.  BTi«bi  iimsnead  plated ttbolCs are  adjas tihir 
fcir  up  to  1  5/3"  nasi  ob  3  and  £  element  and  X"  cm  6  and  10 
element  bfimi ,  All  models  may  tie  motmied  lor  bartzont*  t  0  r 
vertical  CwlariHatiun. 

N«t*  lejiure»  include  adjustable  length  elements,  kilowatt  Reddj 
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hcMi  in-  factory  marked  and  aupfiltad  *ith  mstructfons  for 
quick  naacmblv* 


3  foment 

S  h  lumen  I 

0  (ilrrTlnn; 

tOaiemarJT 

Deicriation 

Mortal  Ho. 

AS03 

AM- 6 

W-fi 

A50-10 

Boom  Lnijti! 

0' 

12' 

30, 

24" 

I.ihW»1  Et 

nr 

117' 

117 

1 17'J 

tuin  Aadiut 

0' 

7' 0" 

tt 

13' 

Fwd  Glin 

7  5  iJB 

9  5  i:-J 

11  9<JB 

13dB 

F'B  flit«J 

20  da 

24  dB 

76  dB 

?BdB 

0*1 

7  I  In 

11  Ibi 

IB  ibt 

?5ltH. 

RINGO 
RANGER 

/or  FM 


4.5  dB*  -6  dB" 
Omnidirectional 

GAIN 

BASE  STATION 

ANTENNAS 

FOR 

MAXIMUM 

PERFORMANCE 

AND 

VALUE 


Cmh  Craft  has  created  another  first  by  making  the 
world's  most  popular  2  meter  antenna  twice  as  food. 
The  neu  Hingu  Ranger  i*  rii>vt>Luped  from  the  haste 
AR-2  with  three  half  waves  in  phtm«  and  a  one  eighth 
wavi  fniitching  stub.  Ringn  Ranger  (rive*  an  extremely 
tow  angle  nf  radiation  for  IwHta  *ignal  coverage.  It  1 
hi  liable  over  a  broad  frequency  range  and  perfectly 
ttiatchfd  to  l?2  ohm  coax. 

ARX-2.  137-160  MHt,  4  lb»„  112" 
ARX-22G.  220-225  MHz.  3  lbi\,  75" 
ARX-450.  435 -4 SO  MHz.  3  lot.,     3»" 

*     Rcfrrviwa  4  wave  dspole 

■  ■  Reference   •*   war*  whip  uaed  a*  gala  ■landaro  bv  many 
m  aitufad urera. 

k  full  quieting  into  more  repeater*  and  extend  the 
radiu*  of  your  direct  eon  tarts  with  the  new  Ringn 
Ranger, 

Yoil  can  up  date  your  present   AR-2  Ringo  with  the 
simple  addition  of  Utls  extend*,  kit.  The  kit  ic 
the  phasing  network  and  necessary  element  extension*. 
Thr>  rmly  modinVationf  required  are  easy  to  make  saw 
slits  in  the  top  section  of  your  antenna. 

AHX-2K         CONVERSION   KIT 


2  METER 

ANTENNAS 


FM 


irv  bnKM     3. 71  dB  -~*-i'-  1  rtfifMH  S  wmn  whip  <    HaUT  win  l*a#Tfc  mn- 
Uiui  wilA  dutct  dc  ground.  U  («m  t**4  Likwi  FL.25S    ia*r  B^glv  nrf 
tun  wltk  l-J   SWF.   FiiJafy  ■r*aa*tmhHH  ud  nady  to  uut*l(    S 
p*rU>  pntoimUfd,  *11  but  490  UHa  tihi  I  ||    mulThnvii 
to  uM  tbaa  an  outer  Fit  miflULU  iufiitnaiTd 


Mp6m  fi'iimhr 

AK-1 

AH-m 

AK-a 

Aa-330 

AR-4» 

Kr^uencv  HMk 

isft*i7a 

i&LJb 

BO-54 

220-«2u 

444-4*0 

Pw*ffp-Hdip  Walt- 

100 

sm 

IUI> 

100 

ne 

Wind  nfirit  a^.  ft. 

n 

31 

W 

.3*' 

ifi' 

H-4  P-OLE  rjp  t^  p  de  Rum  mw  n  'r  w*v"  Jtbete-  OwmlL  (urt*nn*  tertttth 
m  Mil.'  2 J'  220  MHi  —  IS'.  13,1  Mill  I",  pattfrn  3A0*  -  I  d3  Kiun, 
imii  g  dB  irain.  12  ohm  fmwA  UKf«  PU  S3*  eewwtmr.  FsehuKP  im  Imlrn  I 
0Om|il<it«  4 1  polo  [liitmbljet  -ti  lli...uJjlJti(f  buuiTLit  humtris  atld  nil  hui-d^'qr*. 
Vfrtlrii  mpport  niast  not  vuppLtPd. 

ajPtfrOa     114  -  ISO  WHi  1WH1  wsttL  wind  im  2  Si  w)   ft 
ArM-l'4D  220  -MS  MHf    1000  WUtU,  *ntn]  »«■  IKS  *% 
AFV-44P  435  -  f  SO   MHi    1«W  VllLL  wUud  ire»  1  U  «q    fl 


ittbj'i   for  S  mrt#r  |TU 


kll  hkra-uc  Ffemrt  nm  IS  «M   T  B  ratio  14  dB. 


1  K<    1  40  .  turn 


A1«T«ZS  t«0  •  Ul  Xtta  1000  Watt* 


p-TAOi  srracitMc  kits 

htfOn  »rw  and 

AJ4-VFK, 

At*-SK. 

A147-VFK. 

A14T-SK, 

A44V-SR. 


«P  .  wCic&L  IS  It 


luPt*  2.42  aq.    R 


ftor  »m  *»rt x&itr  ppUnacJ  j<^i>  fiwa  1  dB) 
«;m to*t*  i  inimf  ifiai-amc  an 

1  iirffliBl  nu  ■■mill  only 
{»mpl«t*  11  alAMrtt  t±4£king  kn 

Ll   et«rtii>ht  ctntM  nam*4s  only 

0  ^    Ll  4-lcmniit  coax  tauimj  on^y 


C-4  I  II  ELEMENT  YA&i£  Tnr  unndHra  trf  comparisait  in  V|TF-["MF  c-tMH* 
mun!C8ll0tt#,  now  cut  Iqj:  FM  *U4  vtrtltU  [iftLiirtiatJon.  1Tii&  luuf  urU  a\%  aLs- 
ffitnl  modjEla  can  b*  lowir  ildi  m«LUibttd.  All  are  nvtotf  at  mno  whILi  with 

iliftirl  Kt  ijKul  Ewd  dud  I'L-'J-lLf  connm!Ltrr«. 


Modjl  Nllltibvr  AH7-LL 

Bocrni  ■  Lanpert  eJe  144'     | 

W^ht    Turn  rwHw  fl  Lh-,,  TS" 

Omti  f  u  tiitiu  dB  ia  i'la 

Wind  arm.  aq.  ft  IJ?1 

FraqiWKT  SfSt  Ufl-Jia 


F  FM  TWIST 


AHT-4 

3  ItKV  44' 
■ 

M 
49 

na-i4j 


A410-U 

W'li" 
4  It..,  0Gr 

1  a 
«a- 

at 

410^450 


AM':l-fl 

^5"  Sil" 
a  int..  if 
H 

44O-430 


Ali.Ni   I  I 
flllK     M 

itxti 


:2  i   ia  Gun    naj  alaaaaala  banntKl  potnTtll 
and  t«  rliTinU  nrurai  poUna>U4i  far  FU 
ward  n  is  IS  4  dB.  F  B  rata-  21  dB.  Iiaani  trnfih  1»    aMiftd.  10 
U  ofcu  FLXkk   Haifa 


I  *J  a|    ft 


t«r 


AlfT-z&THS-tfT  KHa.  1000  «ittA  *tp4 


HIGH  PERFORMANCE 
VHP  YAGIS 


3/4  ,  1-1/4,  2  MITER   BEAMS 


ird  ol  conipo rturm  In  ■  irutrur  V  HF  TIIF  ronufmnieBi- 
tlOSi  to  ah  l  nit  yagi*  cotnblna  all  oul  performaDrr  and  rrlla- 
hLhtr  v  nh  optimum  aiae  (or  «ae  ot  a&sembh  and  miwbtJtlBl  at 
rour  ailE* 


iJK^t^r'lght  yet  rujiRcd,  t  una*  hove  3/1*"  O,  ti.    ■> 

aluminum  elements  with  D/lff'  crnl^r  aectluns  m^untctlcm  henvy 

iiut.v  formed  bracki3!^.  IkwnnM  11  re-  I"  and  7/S"  O^D,  aluminum 
hii.inn.  Mast  mounts  -.1  i  h"  Eormtd  tiluMinum  haw  ndjuHtahltt 
u^hhll.i  for  up  to  1-1  "V"  O.  ll,  lunula,  They  chji  nl-  ■■-.■>■  i i ■  cl« ■■. I 
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Luctudo  rinta  on  S  meter  T-'M  rafMOtar-  operation- 

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ModH*«ci 
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£krm*nti 
Boom  itafth. 

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fwd   LoSk  = 
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A14*; 

*;  " 

7 

96 

d 

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46 
1  10  I 


4,144  n 
11 

144 

• 
13  OS 

?o  08 

I  to  ( 


n?o  n 

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1*m 

\m 

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11 

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53.50 

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Zero  crystals-  SaHd  state  engineering  enables  you  to  program 
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IC22A 

146  MHz  FM  10  W  Transceiver 

•  22  channel  capacity 

•  1  0  W  nominal  power  output  w/ofie  Watt  low  power  positron 

•  Frequency  range  146  148  MHz 

•  Intermediate  Frequencies  10.7  MHz  First  I.F.,  455  kHz  second  I.F. 

•  .4  microvolts  sensitivity  for  20  d B  quieting,  ,3  microvolts  for  1 2  dB 
SiNAD 

•  Audio  power  —  1  Watt  tnto  8  Ohms 


iC-21A  146  MHz  FM  1QW  Transceiver       S399,  DV  21  Dtgital  VFO  -   S299 


tC-ZlA 

"  Low       miirmoil.      ow      id 
W5FET   RF   Amp  and   5  *»«ll 
cjl     mnr«tv     filter,   P»M»  3    I   F 
t*ftot% 

'  I  DC  'i  ■  CKJ  u!  ■  t  nyn  rpminl  B*a 
wMM*.  I«  Ttiin  irti  urn  ±»nriwid?h 
and  ctunnal  -tptatnr. 
■  Vi'Thiik*  no  intetmed.  D> 
MOS  FET  f»f  amp  and  5  hph-.nl 
cavil  tat  in  ms  from  end  piu* 
I  mi*Bi  and  3  I.F.  flkwt. 

'  ValiabJe      uulpul      puuvar.        10 

MitTt  output  or  enoihet  outinn 
hutwfiort  800  milliwatt*  and  inn 
watli  may  be  lelected  hv  in 
entemal  control. 
■;>WR,  tirtdps.  built  right  I  ma 
the  Iront  nanol  of  me  IC  ?1  A,  It 
an     •GGurati     meter     Tar     VHr 


M  VHf  •nlannf  cajHTMrnwiU* 

*  Thi  IC  Jl  A  zonUiirt  botti  t)l* 
II?    VAC    and    iIh    13  G    VX>C 

OtHWt  VUOfllNfft 

PV21 

*  1-hp  twrfwrt  roTpir-iw  lor 
VOUH  IC  ?l  «'  'C  7\  A.  Th» 
DV  71        II       a       urnaur       di^Llal 

♦yvhftiJfw  is  Lrj'T^letr  vs^r 
ICOM  3  tnatot  vtMtlon  The 
DV  31  will  ajiflfJiTo  in  in  kHT 
Wtfii  Dw«t  ttie  anniiu  2  meiei 
ij.imi  U  uim  oln>  ifijin  tie 
-l^itMcIwi  IpuJnfl  inn  J.  CufTiplfitilv 
iDpniAha  tniottlon  Dt  i  ha  trans 
iTHt  and  t*cttv*  i*  at  n  i  rrip  I  a  am 
inuLrmiu   the   key*    Rvlejise  the 

ITi«    »^|f«h.   »nt|  tlW   ibcOjvu    Ire 
quuncY    It   rflipMvod     There  are 


4 1  CO  TWO  PiuirifnnitbK 
rWTWfiH  1^*    K&^(    IblttftH  l»ni 

Dlex  rVpau>«Acafffc       Vftu,     ^. 
turlpruv    itir    r^ajltp'n    hii)    vavH 
lilriv  ft*  rt««  DV  .<  »n-j-«t 

iri«d  II 

'  A(liiifK*d  t**lwi«  u'  the 
Dv  ?>  Um  ability  la  utilura 
S  kM;  ipllr  forllwv  wdti  <■  10 
icHf   ivrnh«tlJt«t     nm  0  5  hh; 

Ulttvl  jirfttlrlp*  lha  intaA  16  gut 
n' unity  an  mr  (tfjtj|tMnev  tjLjl 
SVBti  In  ihH  fcc*r>  m0i*at  Hit 
channel  m#y  [h«  tcunnnd  iPKf 
undeiitaod. 

~Th«  DV  71  hfll  I  ca|  diNMi  bull  i  in 
117  AC  |>ttvw  *u i H '■' v  «  wall  «« 
iris  »hlllfy  ro  np^ritiw  Unm  ihe 
17  VDC  Un« 


Ti i  h  m  I1HM10  t1i»>i|M  I  ITTh  JOQI   -    15^ 


&0O  (WW  iiVcuKwtw**       11  ■  DO 


DCrliuM  cpr^ncocci  •  BOO 

0*I»'.'C»C!        stoo 


VlJiCU    UtJlK        C  «Ml  f13   9*r 


MifrofMww        $3a» 


ICOM  EAST JNC. 


Haw*n  «,  R«*ni*4  D-r  l*i  12 A      SJ  00 


FdWH)   fiUDDlV   *   '  rl  SRB   r+!" 


•% 


0  fin  Ar;E'«is*^i|>  t'lnot  (B^PI       S?  QO 


H  j  nil  ,ir  Aim m       *X  oq. 


130 


There  is  no  substitute  for  quality,  performance, 
or  the  satisfaction  of  owning  the  very  best. 

Hence*  the  incomparable  Hy-Gain  3750  Amateur 
transceiver.  The  3750  covers  all  amateur  bands 
1 .8-30  MHz  ( 1  60- 1 0  meters).  It  utilizes  advanced 
Phase-Lock-Loop  circuitry  with  dual  gate  MOS 
FEFs  at  alt  critical  RF  amplifier  and  mixer  stages. 
There's  a  rotating  dial  for  easy  band-scanning  and  an 
electronic  frequency  counter  with  digital  readout 
and  a  memory  display  that  remembers  frequencies  at 
the  flip  of  a  switch.  And  that's  just  the  beginning. 

Matching  speaker  unit  (3854)  and  complete 
external  VFO  (3855)  also  available. 

See  the  incomparable  Hy-Gain  3750  at  your  radio 
dealer  or  write  Department  MM*  There  is  no  substitute. 


Hy-Quad 

10-15-20  Meter 
Antenna  3- bands. 

2  elements,  I  package 

Complete  from 
Hy-Gain. 


hioW  J  qua  imame  *rt!  h 

■   ■ 

il 
<*rtiH  Tit**' 

-.("« ■••.  I-  r-  riM  iil  |K»mitH  gutfi  vjicU  elenn*i»l  imNvMiibritv 

1 1       i  it-  d  i  ,  1 1' ■  .i   ^  ii -!■  i  i.  in  ii . 

Mi  HS  Quad  '1-    I* I'--  in   [horoughf>  tented  ai  Hv  '  I  ■•  ■•  ! 

\v*&  -.Hi   in  nsure  -'iiiiirin-.il-  pt?*ik  purkirmorwe 

ii,    ','>       \     I  I  ■■    iinhi  .il-il-l*'  |hi>  M.-J4'  ,h  ,i!    Cdinpfctt    1 1 1  -i  1  ■  Ms  f  i.  in  ■ 


3354  -  SS9  95 


3750-  SI 895,00 


3855  -  5495.00 


There  is  no 
substitute. 


tfltygam 

^y      ^^^^  Amateur  I 


« 


Amateur  Radio  Systems, 


•  I  nrim  dually  timed  gamma  matche*  on  rath  band- 
r illusive  vcrtrx  Feed, 

*  t  uli  vna\e  rlfintfnl  loop*  irqukc  no  tuning  ttubs.  trap*   loading 
(tnl-i  or  balun*. 

*  lliji^oniiillii  potanred. 

•  VbWR  it%<.  than  1.5:1  al  ir*orunct  an  all  bjnd^ 

•  Mounts  on  jny  m^l  1-1/4    to  2-1.2    diameter 

*  52  ohm*  iPTi|inliiiitv. 

•  Accept*  minimum  legal  power  with  efl 

#  Boom  length  8 

*  Spreaders  25  5    overall; 

*  Turning;  i.idHfi  116, 

»  Wrighs  jusl   42  lbs.  complete. 

Older  ho.  244 


Amateur  Radio  Systems. 


$219.95 


. 


H» 


Hy  Gain's  I  ncornpar  a  We 

HY  TOWER 

for  30  thru  10  Meters 

Model  18HT 

•  Outstanding  Omni  Directional 
Performance 

•  Automatic  Band  Switching 

•  Imfalls  on  4  *q.  ft.  of  real  estate 

•  Completely  Self  Supporting 

By  any  standard  of  measurement,  the 
Hy -Tower  is  unqyestionably  the  finest 
mutu-hand  vertical  antenna  system  on 
the  market  today  Virtually  indestruct- 
ible, the  Model  IBHT  feature automatic 
bund  selection  on  60  thru  10  meters 
through  the  use  of  a  unique  stub  de- 
coupling system  which  effect iveJy  ia&- 
latea  various  sections  of  the  antenna  so 
that  an  electrical  14  wavelength  <or  odd 
multiple  of  a  xa  wavelength i  exists  on 
all  bands  Fed  with  52  ohm  coax,  it  takes 
maximum  le^nl  power. -delivers  ouu 
Standing  performance  on  all  hands  With 
the  addition  of  a  base  Loading  coil,  it  also 
delivers  outstanding  perfurmunceon  160 
meters  Structurally,  the  Mudel  ISHTis 
built  to  last  a  lifetime  Rup^ed  hot -dipped 
galvanized  24  ft.  tower  requires  no  guyed 
supports.  Top  mast,  which  extends  to  a 
height  of  SO  ft  ,  is  606IST6  tapered  alu- 
minum AH  hardware  is  indite  treated 
to  MIL  specs.  If  you're  looking  for  the  epi- 
tome in  vertical  antenna  ay  stems,  youll 
want  H/Tbwer  Shpg  Wt.,  967  lbs, 
Order  No.  182  Price:  $259.95 
NEW  .  .  . 

Special  hinged  base  assembly  on  Model 
IBHT  allows  complete  assembly  o1 
antenna  at  ground  level  . ,  .  permits  easy 
raising  and  lowering  of  the  antenna 


MULTI-BAND  HY-QTRAP  DOUBLETS 


Hy-Q  Traps 


* 


■  Install  Horizontally  or  as  Inverted  V 

■  Super- Strength  Aluminum  Clad  Wire 

■  Weatherproof  Center  and  End  Insulators 

-  -  ijfed  hnrftarAiil)  m  4a  «n  imvrtad  V  HvUuh  dkiuhiel* 
**TlJl  Hy-Q  ttmpt  dellvrr  trw  halT  WftVviaAtffli  ^rformitw 
dm  evrfp  d**\£rr  fimjut'-'w  »  Mat^rvd  tr*$»*  irt4»vjduaU>  prt- 
tuned  far  rath  ba«d  feature  iar£r  di.ifnrVr  cthU  dial  devfl-p 
Ail  -\ct-pl mlia.! I y  Li>orah4^  H""  ratio  jn-J  trn  hich  i|  prf 
ffHTHjm:i-    MechdltiCtfMv  *up*ruf  iohlt  oiiim:  ID  boas' 

itts?  pf^>id»'  muxurriin  [pn>t**irtiufi  nnd  nupfMirt  to  ihi'  linidin^ 
coil   Ft'd  will)  52  ohni  cuuji,,  Hy-C-Ain  duublet^  t-mpteiy  wi 
-irrtTHiUi  iilutiiirsum  clud  winicle  itrniid  Hirt-1  wtn-  Li-in. -m. 
thui  dsf)    !'    ■  "Hiriitj'iin  IViimi  M'Jl  wjiIi-i  .iiiil  itnoJte,     a.II  in.' 
.-ir.'hii      vniri-tand    h.M ii-q«uTir--1iik-e    •*  :i  I       SWI?    |i---    Hum 
l  5  J  tm  all  hand*  Sifonu   htU  weight.  *('rflht'rprnckf  t-mlrr 
imuUujrs afv  ind9d«d  Cmm  h:«h  itnpjn  ovuIbc  Hj»rd**,: 
iridnt*-  Ifnted  Xu  Nil.   *|*ci    Hzmvily   trtimtrd   7-inch  mi) 
iTt-u: a!.***  mtrkfcpd  rroni  rtpact  t>oi!«  iixra*  Imlaaif 


8R0AO  BAND  DOUBLET  BALUN  for  10 
thru  B0  Meters  Model  BN-86 

Tht'  model  HN-^  twlun  fimvidt?!-  optkmuoi 

btLkuirji  iif  PQMrVT  t^i  bjrli  (idtBafan)'  Hunlilri; 
dnd.  vufcllj,  imphavwh  ih*-  irwnsfer  <if  ^in'ruy 
f Wrlli  M'mJIiphj  id  antfcnrm  Power  <"j|)4riJy  (p 
1  KW  IJt  Ki-iiUiri'»*f.iihi'ttii'iiiftiun*ltu(tiiiri 
#nd  built-in  tmummg  bradtets  S15  9E 
ShW  Wl    I  »b    Oatf  hlft  242 

Hy-Gain  REEL  TAPE  PORTABLE  DIPOLE 
for  10  thru  80  Meters  Model  1 8TD 

The  most  portable  high  performance  dipole  ever... 

Thi«  >1^id*r|  IflTLu.- iiriitiit--.tiiirt.itfl>  eJli' mhnt  ri><i.lpnjr>f  ht^fM^T*  Ci  ii^rtn^le 

rJuyblt'l  unti.'nnj  *y*t«m  rvi-i  dev^kiped    It  rut^  pri>vtri  tnvMlunblt  in  \i\w\  ntniM 

reii   I  iinumiicaimrifc  in  vital  mllunn  Mini  oammriviil   ...|l ■.-  thjtrtitth 

i.yt  th*-  »<irlij  T*tJ  PuLinktM  at*H  topM  i  ,il-l'r,n-.-d  in  n BXt^od  frt«tn  i'liht'i 

aide-  i  if  tb#  nuiili  h  i  !>  :.j!    I  -  - . .  f . .  ■  -  .-.I  ]j'2  fwl  fiir  if  =i  mc  -j^Tntifm 

2Ti  ti    Irn^lhr  kJ  fiiiiv(»iij|i»  U  tn  n.ipr  iti-.  i  each  Upc  [rmii!?  init«ll|itHin 

to  pdlr*  trrr*  tMitdsn^i     ■  listen  4ilutilt-  fof  farming  *  duubitf  jfttr nn. 

Ir-T-^r.i'    ::     -.   iht    hi^h    impact   hwimiit:    u.  a  fft^u<-ivi    to   leftfftla  wn  dLBTt 

bnMfld  M  metwr  mr*>«irrmt-nXT  «>n  tnt  lafir?     nuikin  m*iaiJuinin  f-mipn^*   ft*d*  > 
hi  #hm  ctNU    Dr:i-rf  ■    njT»undjru:  prHbrmukis  i*  a  (wctahJir  lt  pfrrmui«nt  <nMaiLiiMn 
Mvuur*  -m  wnKid      IV I     itlW    94 » 

Order  No  2Z& 


CENTER  INSULATOR  for 
Multi-Band  Doublets  Model  CI 

SttTift*.  lt^  -ii,  HvatbaprcoT  MivM  CI 

-rtJded  frnbi  tu^h  irtijMct  Ofiti*:    Kardwir- 
.ridite  lrt*lrd  to  MtL  i|MKK  AffepU  W  or 

'*   ocwxiat  »hU'  ShfTi  Wt .  0  ti  Ibn    SS  95 

Or-der  No.  155 
PORTABLE  ANTENNAS 

Rugged,  durably,  continuously  loaded  antennas  designed  for 
portable  applications  ConsTrucled  to  withalanrJ  rough  han- 
dling Completely  insulated  with  vinyl  coating  Can  be  bent  al 
ali  angles  mlhout  destroying  or  cracking  proiectiwe  finish. 
Cannot  be  accidental^  shorted  out. 
Frequency  136-470  MHz  {specify  model  I 

VSWR  2  0  to  i  or  less 

Loading  CoM  Ptated  wire  sjtver  solder  cad  plated 

brass  base 
Model  274  -  S9  00    Modei  27&  -  S7.00  Model  269  -  S7.00 

MDOCL  2BDQ  rc»r  40a«iriBQmw«   100  IO't   whiH    r- 

rru>  i^Ba1  flow.  *»ipe  wt,  7.5  ibi.S49.9B 

MODEL  5BE)Q  itn   lu.  lb.  20,  40  *i*d  80  mrterl,  *W   0v*r*H    Eakai 
OtOer  Ma.  3B  J 

Hy-Gain  SINGLE  BAND  DOUBLET  Model  HD4 

Hiah  pMf«rrt»nr*  iinpi*  hand  4t»u^M  hrrtalik  hnflftintaUf  CT  a* 
irtfTTlod  V  Jmkr*  :**>+*■  P  Stfpl^Mt  *H  h  rutUn^  tsutruc- 

linn*  far  IU,  15  30.  40  arwmr'tr  aprrat*m  t^KUpMr  with  nuts 
j1  ijh:  center  jntl  ead  iruuiar-.  >:tJ5S  L'  and  BHCHaazyooppar 

tlad  grandad  «l*fl  win?  Shp«    M'l   3  J  Ihs 
Ordnr  Na.  114 


END  INSULATORS 
for  Doublets  Mrulel  El 

Hiiiijfed  7-inrh  r>nd  insuJaiurn  art"  muldt-d  fn.ni  high  irnpwrl 
cyuJac  thai  i»  heavily  wrratcd  Id  Lnocdtr  kakagr  path  in 
approsnnalalv    VI   inches.  Avaifahk-  id  parr*  unit    Shpg.  Wt  . 


131 


•  Remote 

•  Motor 
Controlled 


RCS-4 


COAX  ANTENNA 
SWITCH 


•  Control  unit  works  on  110/220 
VAC.  50/60  Hi,  and  supplies 
necessary  DC  lo  moloi\ 

•  Excellent  for  single  coax  feed  to 
mullihand  quads  or  arrays  of 
monobanders  The  five  positrons 
allow  a  single  coax  feed  to  three 
beams  and  two  di poles,  or  other 
simtlaf  combinations 

•  Cortrol  cable  (not  supplied  1 
same  as  for  HAM-M  rotator 

•  Selects   antennas   remotely 
grounds  all  unused  antennas 
GND  position  grounds  all  an- 
tennas when  leaving  station, 
"Rairv+ktf""  cons t ruction  shields 
moror  and  switches 

•  Motor  24  VAC  2  amp,  Lubrica- 
tion good  to  —  «PF. 

•  Switch  RF  Capability  Maximum 
legal  limit        Price:  Si 20.00 


MATCHING  NETWORKS 


MN4 
200  watts 


Price:  S1 10.00 


MN2000 
2000  walla  PEP 

Price:  $220.00 


General  •  integraJ  Wirrmoler  reaos  '  srrj  j:o*b*  in 
w*TT5   and    VSWtf   d<r«Cll>,    tan    te    CHli&ratHfJ   10   r*§0 

ficchni  power  *  Matches  50  ohm  transmitter  output  to  coax 
antenna  fe  v$AR  at  at  least  5  t  •  Cover*,  f-.jm 

band*  80  thru-  tQ  meter*  •  Switches  in  or  Otrt  w«Ih  rronl 
panw>  switch  #  Site:  £  VH  1QVW.  BWD  (14  Q  «  27.3  x 
2EJ.3  cml.  MN^OOO    U'i"D  (36  5  cm}. 

•  Continuous  Duty  Output:  MN-4.  2DG  ttrtfBl  MN  2000, 
1000  waits  12000  wait!  PEPl  *  MN-2000  only:  Up  iq  3  an- 
tenna connecters  selected  by  front  panel  switch 


RF 

WATTMETERS 


W-4  1.8-S4MHZ    Prrce:  S    72  00 

WV-4       20-200  MH*  Price;  S    84.00 


ReaiJs  '-'ward  and  reflected  power  directly  In 
watts  (VSWfl  tt^m  nomogram).  Two  scales  in 
SU«;5VH    3»-"Wt  4T>  (14.0  * 
2  cm) 

Model     Full  Scale  Calibration  Accuracy 

200  watts      !&*•  ,J  reojirg  —   2watti) 
2000  well*    >(9%Olfea  20  watt*) 

100  watt*    ±l5\,  ol  readrnq   ■     1  wall  J 
1D00  watta    *  15S  of  reading  -  10  waits) 


W4 


VYV-4 


DRAKE 


SSR-1 


COMMUNICATIONS 
RECEIVER 


*  Synthesized  •  General  Coverage 

*  Low  Cost  *  All  Solid  State  •  Built-in  AC 
Power  Supply  *  Selectable  Sidebands 

*  Excellent  Performance 

PRELIMINARY  SPECIFICATIONS:  *  Coverage:  500  kHz  to 
30  WHj  •  Frequency  G*rt  be  read  accurately  to  better  than 

5  *Hj  *  Semiltvity  '  rpicaJly  5  microtis  lor  10  dB  S-  N  H 
SS9  ana  frefier  than  2  microvolt*  Iqr  10  OB  B*H  Nl  AM 
•  Selectable  tideband*  •  Built-in  power  lupply:  117/234 
VAC  ±  JO".  *  »  the  AC  power  source  laile  trie  unil  switches 

auiomatJcaUy  to  an  internal  battery  pack  *m  ch  uses  e  it 
D -cells  (not  supplied)  •  For  reduced  current  drain  c  DC 
operiitagn  the  dials  do  npt  Jtght  up  unless  a  fed  pushbutic-^ 
on  I  he  t»on1  panel  is  depressed. 

The  pGriormSrtee,  wrsatlliiy,  size  and  low  Cast  of  Ihg 
SSFM  make  It  Ideal  tor  use  as  a  stand-by  amateur  or 
no  vice  amateur  receiver  short  wave  receiver.  CB  monitcr 
receiver    of  rjurieral  purpose  laboratory  receiver 

Prtco:  $350,00 


l 


GENERAL:  *  All  amateur  bands  10  thru  30  meters  m  seven 
60C  kHz  ranges  •  Solid  State  VFO  with  i  kHj  dial  4i  visions 
•  Mod**  SSB  Upper  and  Lower.  CW  and  AM  *  Built-in 
Sideline  ana  MftOfWl  -  ?*itchrng  on  CW  •  30  tubes 

and  semi-conductors  •  Dimensions:  Sh**H    t&Hl$i.  M 
D  (14.0  i  2?  3  *  3&  5  cm i  WL:  16  lbs  (7  3  kg} 

TRANSMIT  •  VOX  or  PTT  on  SSB  or  AM  a  Input  Power 
553  300  warts  PEP;  AM  260  walls  PEP  controlled 
career  compatible  wuh  SSB  linear*:  CW,  260  watta  a 
Adiustabf*  pineiwortt. 

RECEIVE:  ■  Sensitivity  belter  than  ft  J4V  tor  lfj  <jB  S-'N  • 
IF.  Selectivity  2  i  kn?  \*  5  dB,  36  kHz  @  ©0  dB  *  AGC 
full  on  leceive  modes,  'variable  with  PF  gam  connol.  fast 
attack  and  slow  release  with  noise  pulse  suppression  a 
Diode  Detector  tor  AM  reception         Pfjc©:   $699  00 

34-PNB  Plug-In  Noise  Blanker  ....  100.00 
FF  1  Crystal  Control  Unit  ....,..,  46.95 

MMK-3  Mobile  Mount 7.00 

RV-4C  Remote  VFO 120.00 


TR-4C 


SIDEBAND  TRANSCEIVER 


POWER  SUPPLIES 
AC  4  Power  Supply 
DC-4  Power  Supply 


$120.00 
.  135.00 


DRAKE 


2  Meter  FM 

Portable  Transceiver 


MODEL 


TR-33C 


Amateur  Net  $229.95 

SCPC*  Frequency  Control 

1 2  Channels  with  Selectable  Xrntr  Offsets. 

All  FET  Front-end  and  Crystal  Filter  for  Superb 

Receiver  Intermod  Rejection. 

Expanded  Antenna  Choice. 
Low  Receiver  Battery  Drain. 
Traditional  R.  L  Drake  Service  Backup. 
Single  Crystal  Per  Channel 


LINEAR 
AMPLIFIER 


i-4S    Llf^SC    ^fFlpSi  +  irt. 

•     2000     ffatti     PEP  SSB 


L-4B 


ra^oo 


B 


Grounded  Gr<l  1SOGZ   Tube*   ■ 

ftrcvd  Bond   Tomd-IHp«f   •  ftf    n|Bptrt« 
FeedhMdc    •    Tr^r^m.TT.r^j    AGC   •  Din c- 
iioeiat  ftirjnwtv  *  f  «o  T*u(fa»nd  Stciptn 
nun  MTtar*  *  L4B  Iff'W     .'  1  B    H 

14-5  ieo.  Wi,.  3  •  Po***  SoWiv 

61  A   IV    f7/6M   |l    I)  wi     43  «bj 


PCftVER  SUPPLIES 

AC -4  PnrtitM"  Stunn-i 
DC-4  Pnwwi  Supply 


Siru.oo 
tnson 


TUI  MAY  BE  ELIMINATED 
VI    WITH  THESE  DRAKE 


FILTERS 


rv-5200-U*  t'otrtwilv  TV-IOGO-lPj 
^ated  1000  uvuui  tefiu-1   ?0O  watts  en  6 
meiflU   SO  ?3r}j-.jfmt>c1cKi  huttiin   $19.95 

TV  42  LP 

if  a  lour  »cimn  titter  deue)n*d  with  43  ? 
MHi  cuE<rtt  afldi  eMiremeiy  h»<jh  jnpn. 
lion  in  ail  TV  £tiafinfeht  for  citifem  tand 
«rK]  atn#i  Tf^ntm.iTe*4  3£)  MHf  ani  lower, 
Rji»ti  %  00  warn  incut,  SD-239  connecnofi 
IjulI:  .n    SI  0,55 

TV  3300  LP 

10P0  W4tll  "u  •    t«-l^v.  30  MHz.  Anprtja  . 

Iwn  beua<  tnun  SO  rfS  above  41  MKf.  SI  9  95 

TV  300  HP  High  Pa»  FiJtar 
piovitJci  mori*  than  40  dB  ll  lenufltrun  at 
52  MH:  jnri  loner  Proieoi  she  TV  «ai 
hem  amatvui  transmilT** •  G  thru  1U0 
meten    48.95 


Radio  Electronics 


JWM*mST 


61T 


MA  02136 


NEW  ENGLAND'S 
FRIENDLIEST  HAM 

STORE 


132 


IF  YOU  ARE  ON  144,  220  OR  432  AND 
HAVE  WORKED  A  REPEATER... 


THE 

TX144B 
TX144B 
TX220B 
TX220B 

TX432B 
TX432B 


%hf  engineering 

WORLD'S  MOST  COMPLETE  LINE  OF 
VHF-FM  KITS  &  EQUIPMENT 


Kit. 
W/T. 
Kit. 

W/T. 

Kit . 

W/T. 


transmitter  exciter  —  1  watt  — 

2  meters      ...... 

same  as  above  —  factory  wired 

and  tested      .  ,  ,  .  , 

transmitter  exciter      1  watt 
220  MHz 
same  as  above    -  factory  wired 
and  tested 


»      »       ••       k      •      *      *■ 


*      •      »       . 


. 


transmitter  exciter  432  MHz    . 

same  as  above  -  -  factory  wired 
and  tested 


»•*-.**«»» 


RX50C  Kit  . 
RX144CKit. 
RX144CW/I 
RX22QC  .  ,  . 
RX432C  Kit. 


HTU4B  Kit.  , 

PA250IHKit  . 

PA2501H  W/T. 
PA4010H  Kit  . 
PA4010H  W/T. 
PA144/15  Kit. 

PAH4/25  Kii  . 
PA22Q/15  Kit. 


30-60  MHz  revr  w/2  pole  10.7 
MHz  crystal  filter .......... 

140-170  MHz  rcw  w/2  pole  10.7 

MHz  crystal  filter 

same  as  above  —  factory  wired 

■&1  flU        IvJ'vCI.,  m         p       #        #        f         d        -ft         *         -I  r         ■         +         ■ 

210-240  MHz  revr  w/2  pole  10.7 

MHz  crystal  filter 

432  MHz  revr  w/2  pole  10.7  MHz 

crystal  filter 

accessory  filter  for  above  receiver 
kits  gives  70DB  adjacent  channel 
■  ejection      «■*«..  **.*«>** 

2  meter  —  2w  —  4  channel  —  hand 
held  xcvr  with  crystals  for  146.52 
simplex    ,,,,_,.  ..*.»*.» 

2  meter  power  amp  —  (tit  1w  in  — 
25 w  out  with  solid  state  switching, 
case ,  connectors    .......... 

same  as  above  —  factory  wired 

and  tested 

2  meter  power  amp  —  1 0w  in  — 
40w  out  —  relay  switching    ,  ,  t  . 
same  as  above  —  factory  wired 
and  tested      ..,*,,,,,,.,, 
2  meter  power  amp  —  1w  In  — 
1 5w  out  —  less  case,  connectors 

and  switching      

similar  io  PA144/15  kit  except 

similar  to  PA144/15  for  220  MHz 


$   29.95 

49.95 

29.95 

49.95 
39.95 

59.95 

59.95 
69.95 
114.95 
69.95 
79.95 

8.50 


129.95 


39.95 

49.95 
39,95 


It  was  probably 
this  one. 


The  RPT  144B,  RPT  220 B  and  RPT  432  are 
self-contained  —  all  solid  state  machines.  Corn 
servatively  rated,  high  quality  components, 
assures  EXCELLENT  RELIABILITY.  Careful 
consideration  has  been  given  to  both  interfacing 
and  control  flexibility, 

RPT  144B  or  RPT  220B  Kit  • $46596 

RPT  432B  Kit 515.95 

RPT  1448  or  RPT  220B 

factory  wired  and  tested 695.95 

RPT  432B  factory  wired  and  tested    .  . .  795.95 


PA432/lOKi1  .    power  amp  -  similar  to  PAT  44/15 

except  10w  and  432  MHz      ....         49.95 

PA140/10  .  .  >     10w  in  -  140w  out  -  2  meter 

amp  -  factory  wired  and  tested    .       179.95 

PA  140/30  .  .  .    30w  m  -  140w  out  -  2  meter 

amp  -  factory  wired  and  tested    .       159.95 

RPT144  Kit  .  .    repeater  -  2  meter  -  15w  - 

complete  ((ess  crystals) 465.95 

RPT220  Kit  .  .    repeater  -  220  MHz  -  T5w  - 

complete  (less  crystals)     465.95 

RPT432  Kit  .  .    repeater  -  10  watt  -  432  MHz 

(less  crystals) 515.95 

RPT  144  ....    repeater  -  1J  watt  -  2  meter  — 

factory  wired  and  tested     695.95 

RPT220  ....    repeater  -  15  watt  -  220  MHz  - 

factory  wired  and  tested     695.95 

RPT432   ....    repeater  -  1  0  watt  -  432  MHz  - 

factory  wired  and  tested     .....      749.95 

PS3  Kit.  ....    12  volt  -  power  supply  regulator 

PS15C  Kit  ...    NEW  -  15  amp-  12  volt  regulated 

power  supply  w/case,  w/fold-bacfc 
current  limiting  and  overvoltage 
protection .  *  .         79.95 

PS15C  W/T   .  ,    same  as  above  -  factory  wired 

and  tested      .  .  . 94.95 

PS25C  Kit  .  ,  .    NEW  -  25  amp  -  12  volt  regulated 

power  supply  w/case,  w/fold*back 
current  limiting  and  overvoltage 
protection     .  ,  .  .  .  ^  .  ....  ,       129.95 

PS25C  W/T    .  .    same  as  above  -  factory  wired 

and  tested      . 149.95 

OTHER   PRODUCTS 

BY  VHF   ENGINEERING 

CO  1  Kit  ...  .    10  channel  receive  xtal  deck 

w/diode  switching 6.95 

CD2  Kit  ....    10  channel  xmit  deck  w/switch 

and  trimmers  ......... 14.95 

COR2  Kit  .  .  .    complete  COR  with  3  second  and 

3  minute  timers     19.95 

SC3  Kit    ....     10  channel  auto-scan  adapter  for  RX    I y .95 
Crystals    ....    we  stock  most  repeater  &  simplex 

pairs  from  146.0-147.0  (each)     ....    5.00 

Synn  II  Kit  .  .  .  synthesizer  kit  for  2M  FM    .   169.95 

CW1D  Kit  ....  automatic    identifier  for  repeaters, 

RTTY.etc 39.95 

CWID  wired  . .  same  as  above  -  wired   .........  49.95 


133 


Build  a  2  meter  or  220  MHz  Transceiver 


10  Channel  Scanning 


1 5  Watt 


You  can  put  it  all  together  for  only  $219.95 


RX144C  or  RX220C  Receiver  Kit 


PA144/15  - 15  Wan  Power  Amplifier 


TX  144B  or  TX220B  Transmitter  Kit 


SENSITIVITY  JuV  for  20db  quieting.  SQUELCH 
THRESHOLD  .2uV.  AUDIO  OUTPUT  2  wans. 
STABILITY  better  than  -.002,  IMAGE 
REJECTION  60db.  SPURIOUS  REJECTION 
greater  than  60db.  IF  REJECTION  80db.  FIRST 
IF  10.7  Mh*.  SECOND  IF  45S  Khi.  BANDWIDTH 
15  Kh*  at  3db,  60  Khz  at  30db  (40  Khz  with 
optional  4  pole  filter^  CRYSTAL  45  Mh/  parallel 
at  20pf  (HC/25U  holder). 


POWER  GAIN;  12  dti  nominal,  INPUT  POWER;  2 
waits  max.,  INPUT  VOLTAGE;  12  to  14  volts  DC 
negative  ground,  INPUT  CURRENT;  4  amps  max*, 
STANDBY  CURRENT;  virtually  insignificant, 
INSERTION  LOSS*  less  than  1  db  on  receive, 
DUTY  CYCLE;  50%  or  less.  Consists  of  drilled 
glass  PC  Board,  heat  sink  and  ail  components. 


A  one  watt  exciter  using  four  RF  transistors,  two  diodes, 
and  one  integrated  circuit  The  RF  transistors  are 
operating  well  below  their  ratings  allowing  long  keying 
periods  without  damage.  •  Nominal  output  1ft  watts  • 
Deviation  adjusted  to  lOKHz  •  IC  audio  with  clipping  and 
active  filter  •  AM  spurious  outputs  down  30db  or  more* 
Temperature  compensation  crystal  trimmer  •  Zener 
regulated  oscillator  •  Uses  readily  available  12  or  18  MHz 
crystals  (18MHz  for  220)  •All  tuning  coils  prewound  • 
Pred rilled  and  tinned  G- 10 Circuit  board 


CD-2  Crystal  Deck 


SC-3  Scanner 


CD-I  Crystal  Deck 


Capable  of  stunning  up  to  10  channels.  Scan  delay 
allows  both  sides  of  a  conversation  to  be 
monitored  without  the  scan  starting  each  time  the 
carrier  drops,  The  priority  feature  allows  the  user 
to  program  the  scanner  to  return  to  his  favorite 
channel  whenever  ft  is  active. 


Designed  to  provide  multj -channel  operation  for 
the  TX -series  transmitters.  It  features  an  extra  set 
of  contacts  that  may  be  wired  lo  the  CD-I  crystal 
deck  for  10  channel  transceiver  The  extra  contacts 
may  also  bu  used  to  switch  L.E.D.  indicators.  The 
switch  has  1 1  positions, 


A  ten  channel  receiver  crystal  deck  which  utilizes  diode 
switching  to  select  the  crystal  position  required. 


Complete  with  cabinet,  speaker,  hardware,  L.E.D/s,  alt  accessories  and  full  assembly  instructions, 

(Crystals  and  microphone  not  included,) 


WORK  ALL  REPEATERS  WITH 


OUR  NEW 


SYNTHESIZER  II 


The  Synthesizer  II  is  a  two  meter  frequency  synthesizer. 
Frequency  is  adjustable  in  5  KHz  steps  from  140.00  MHz  to  149.995  MHz  with 
its    digital    readout    thumb    wheel    switching.    Transmit    offsets    are    digitally 
programmed  on  a  diode  matrix,  and  can  range  from  10  KHz  to  10  MHz.  No 
additional  components  are  necessary! 

Kit $169,95      Wired  and  tested $239,95 


134 


AAGONAUT    MOOiLUI  AWtlFlER  MOOf  L  * 

irar 

TEN -TEC 


TRtTO*  IV 


Model  206 


TRITON  IV  A  raw  puth -poll  final  ampin 
I  Mi  wiiti  ihc  latest  flold  rrwiati* «l.  jenei 
protected  trsfmnofc.  opwimng  =?i  200  <npm 
w.mi  on  alt  hf  bandi  3  b  ihtouuti  29.7  MHz. 
P'ui  •  ntw  Crygfal  tefvodyne  VFO  lor 
»mpf0v*tf  ineurr  and  tofle  lerm  frequency 
tl*l>flfttr   '»"**  uwlonn    I    k*it  tmUc-UT  rEHCtli 

lion,  rwn  an  t-n  meter  l  Umuipf  tied  l*4et 
trvrty  4  yowl  wtlh  1hr  rte*  «i0||  pot- 
crrtlal    Mtef ,  and  «nprov*d  tflurtpus  rsjet- 
T«on     'rtutn     from     the     i«a     »C    double 
balanced  mixer. 

M#"t  tmall  tvttirl  rrrxn  Qvemenri 
ih'outjhnur.  taken  cottfrGlivaly,  =>dri  more 
QmtormuncE  and  quality  plum  such 
'hinm  a(  »ndiuidua1  rtmpWiiEUrc  corrfjfirv 
Htld  Intwrfrated  circuU  Yi>ll,H|it  fugul&lnn 
Fur  lirifil  Irlai  contrfjt  and  VFO  '-opply,  And 
torold  inductances  in  rh»?  fen  nnd  r if te^ii 
mai&r  low  pas?  itftBtf,  LEU  mrJicutnrs  Fur 
oifvft  lumng  and  ALC  ituvihultJ,  accessory 
tockit  tar  added  flexl Willy,  und  wquen- 
tuiUy    teyod    mule.    AGC    imd    iransmittaF 


cocuot  loi  ewen  t»n«f  stuped  and  chckles* 

TRITON  fV  S699.Q0 

12  ac   luuply    wilt)  a  tail  I -m  wieaVe*  and 
VOfc  -  2B2G  SI29.00 

ARGONAUT.  MODEL  SOS 

Cowt  jUI  Ajtbiiw  hands  10-BO  merer  t 
9  MM*  crystal  feu*.  2.5  •  Mr  terdmrflk  1.7 
*h*p*  Ijctfii  #  fi/SO  dfi  P uuil  t  Potnet 
riquircd  17  15  VDC  #  150  P<nA  hkvw.  80D 
rtiA  troftevnit  al  rated  output.  Construct  on 
-iluminuin  chesui  fOO  and  lionl  panel, 
nnpldvd  pl«tic  end  pjntH  Ocam  iiom 
panel,  tualiuit  vinyl  ion  and  end  mm.  Sua 
HWD  4    "  *  1 3  '  *  7"   WiHghf  6  lb* 

LINEAR  AMPLIFIER.  MODEL  405 

Crivwrt  all  Amaittur  twnclt  10'&C1  mem*. 
$0  VWltH  OUlpui  |inw»r,  CdriliiinriUE  sins 
DVftVa.  RF  watirnBlirr.  SVVR  rrWer,  Puwur 
rtquiffd  12-15  VDC  @S  A,  mux.  Conaruc^ 
i  luri  uuminum  I'tijiuii,  lop  nnd  Itorn  panel . 
moldiHl    pidKic   fide    purwlt    Q^am   from 


M  »nr  I     walnut  vinyl  tpp  end  Crttf  tf  jm.  Si/e 

mwo  -r  J  *  7"  m  r"  Wfnoht  71.  iin. 

Ar^otMui.  Model  599 S329.0O 

L.™  Amfi4Ff«r .  Moii.1  405  159  «1 

Po*#t  Supply,  Modti  26 1 

'Will  power  both  uruul  79,00 

Pow*r  Supply.  Model  210 

l Will  poNEt  AiJilMll  orrt¥|  .  „ 77.50 


MODEL  206  CRYSTAL  CALIBRATOR 

SPECIFICATIONS 

Kqv*?r  R«iui«  ed:  9  to  1 7  VDC  #  8  mA. 

FundatTWital  Fret|temev    I  AC  *  Hz 

Chicuit  Dttctrplksfi  Pierce  crvitnl  Dfcilfcatnr, 
■  allPwed  by  Schinill  in^rr  Outpur 
diHERd  Frnm  uniiurnfiufi  nu.illiifnr 

Calibration:  AdjuitiiblD  tr>  WWV  with  in- 
'ml  vurkable  capsdtQj 

:.i.ii    HWD  3-1 /S"  »  43/ir  .  4-1/8" 

Woltiht    H  lb, 

Model  206  CryttAl  Calibraiot S2&.9b 


KR20  A  ELECTRONIC  KEYER 
A  fine  instrument  for  all-around  h>gh  perfor 
miafice  electronic  keying.  Paddle  actuation 
force  is  factory  adjusted  for  rythmic  smooth 
keying.  Coniaci  adjustments  on  front. 
Weighting  factor  factory  set  for  optimum 
smoothness  and  articulation,.  Override 
"straight  key"  conveniently  located  for 
emphasis,  QRS  sending  or  tune-up.  Reed 
relay  output.  Side-tone  generator  with 
adjustable  level,  Seff-completlng  characters. 
Plug-in  circuit  board.  For  117  VAC,  50-60 
Hje  or  6-14  VDC  Finished  in  cream  and 
waEnui  vinyl.  PRICE  $67*50 

KR5-A  ELECTRONIC  KEYER 
Similar  to  KR20  A  but  without  side-tone 
oscillator  or  AC  power  supply.  Ideal  for 
portable,  mobile  or  fixed  station  A  great 
value  that  will  give  years  of  troubtefree 
service.  Housed  m  an  attractive  case  with 
cream  front,  walnut  vinyl  top.  For  6  14 
VDC  operation.  PRICE  $3850 

KR1-A  DELUXE  DUAL  PADDLE 
Paddle  assembly    is   that   used   in  the  KR50, 
housed    in    an    attractive    formed    aluminum 

CflS«  PRICE  $25.00 

KR2  A  SINGLE  LEVER  PADDLE 

For    keying   conventional   ''TO"    Of  discrete 


character  keyert,  as  used  in  the  KR20  A. 

PRICE  $15.00 

KR50  ELECTRONIC  KEYER 

A    completely    automatic    efectfonic    k«yer    fully 

adjustable  to  your  operating  style  and  preference, 
speed,  touch  and  weighting.,  the  ratio  of  the  length  of 
ditv  and  da  hi  to  the  space  between  them  Self  con- 
trolled keyer  to  rramnm  your  thoughts  clearly,  artfeu 
lately  and  almost  effortlessly  The  tarritiic  (squeeze] 
feature  allows  the  insertion  of  dits  and  dahs  with 
perfect  tuning. 

An  automatic  weighting  system  provides  increased 
character  to  space  ratio  at  slower  speed*,  decreasing  as 
the  speed  is  increased,  keeping  the  balance  between 
smoothness  at  low  speeds  and  easy  to  copy  higher 
speed  Nigh  intelligibility  and  rythmic  transmission  is 
maintained  at  all  speeds,  automat rcaii  ♦ 

Memories  provided  for  both  dits  and  da N  but  either 
may  be  defeated  by  switches  on  the  rear  panel.  Thus. 
the  KR50  msy  be  operated  as  a  full  iambic  {squeeze! 
keyer,  with  a  single  memory  or  as  a  convent kinal  type 
keyer.  AH  characters  are  self -completing 

PRICE  $110-00 


SPECIFICATIONS 
Speed  Range:  6  50  w. p.m. 
Weighting    Ratio    Range;    50%    to 
classical  dit  length. 


150%    of 


Flip  — 

You  Use 

It 


Flop  — 
You  Hide  It 


Fits  new  or  existing  antenna*  up  ic 

48"  long 

No  unsightly  holes 

Mounts  on  trunk  rain  channel,  left  rear 

position  advisable 

InVtructtofiS  and  mourning  hardware 
included, 


9 


SHUR-L0K 

SHUftHLO*  »FG    CO 


Kelps  prevent  I  heft  of  CB  Radios  and 
antennae  Antennas  are  the  lirat  thing 
thieves  loafc  for 

Ahows  automatic  car  washing  without 
dismantling  ihe  antenna 

Same  or  lower  $  W  R.  than  conven- 
tional trunk  fnount  installations 


IMC 


!*1  3fc^-U»  M»a   ts 


Memories:    Dit   and   dan.    Individual   defeat 

switches. 
Pad dte  Actuation  Force:  5-50  gms 
Power    Source:     117VAC,    50  60    Hz,    6-14 

VDC 
Finish:    Cream  front,   walnut  vinyl  top  and 

side  panel  trim. 
Output:    Reed  relay.  Contact  rating  1  5  VA, 

400  V.  max. 
Paddles:     Torque    drive    with     ball     bearing 

pivot. 
Side  tone:  500  Hz  tone. 
Adjustable  output  to  1  volt. 
Size  HWD:  IV*'  k  57,"  x  854" 
Weight:  1%  lbs. 


Tell" 

TEM-TEC 


KRB0A 


fijf  SHUH-L0 


Disappearing 

Antenna 
Mount  si i.95 

HOuai  »m  kcvck  nuMk  g#  mil 


Futly    VSWB    8t   reverse  voltage   protected 
No  tuning)  required  across  band 


•  Switchabie  Class  C  or  AB  operation 

•  Built-in   TR    switching,  w/increased   delay 
for  SSB 


Fully  compatible  with  all  1-ISVtf  FM/SSS. 

AM/CW  rigs 

AH  soiid-state  and  mjcrostrip  construction 


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220  2. 

1  3M10  6OL 

ID 

60 

7 

7  1X1Q2X1G5 

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10 

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i 

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7  1X10  2X16  5 

J  39.95 

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■s.21    '  vh  k  i  r  "i*  ■*  i  :■  n 

Wtlghl:  -I.- 
l.BNHi   | 

. 

Powtr  l-i|iui . 

cw  ioon-«ifrQ(:to 

;M0  ^j!-i  EC  uip-.jl  ■??■  iTiuinlt (onniuctji 
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Th-J-aiiUi  Phiertioit.  Ui>*ri   Jl  m*%i 

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i      =EQ  Ihiij   ia™*l*:i 

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CD-Dl  llig  (.Kl  Ml  Ul- . 

*  L-Ompjt!    I(:  ft-.p  i  m  |  i[. .  ;3|(J .   flriB-(iifcr»   CJhi»i(-t. 
lu-bi  .-jul:i^  rhumUfr  ttln:  IftJin  Haai]  ^r 

|i«rruiJt1nl  ijiniifi, 
•■     CttrMt  WARS  f  i;aut«>tlCl  WilMlqiil    iinrt|P|ca(hDm 

■  BrojJi*n^(fij  in.pu  t  »nd  op  mm  tl(EU  II 

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WMJGQQ    in  une    WStt 

meter  Wtth  Muscle  Stales 
to  2O00  watts  New  ffat 
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549  95 


WMJO0O  Peak-reading 
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powef  trwn  with  the  flick 
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WM 1500  Hign  Accuracy  m 
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?  to  50  mhx  Forward  and 
reflected  power  use  it 
lor  trouDte-shooting  too 

seats 


ELECTRONICS 


Hams  the  world  over  value  amateur  radio 
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Fully  'iuhd-Hijiip.  unitiufl  brrmiJ- 
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FFP  inpul  on  any  frequnnrv 
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ll\CAt  AMFMFIEl 

Ta  ci(jddrupU>  th«  ntpst  ad  the  MOB 
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-    11 1  m  aney .  $6-49, 9  & 


12m  t 


Additional  Swan  products  include  fixed 
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only  Swan  Electronics  offers  facto 
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^-^      ELECTRONICS 

*  1  -Ti   t"  •  . 


TECHNOLOGY 


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Mod.  4220-3  4  cav.  220  MHz 
insertion  loss  0.6  db  with  80  db 
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U.S.  Radio  Amateur  CaN book      . St 3.95 

A  R..R.L.  Radio  Amateur  Handbook  $  6.00 

A.R.FLL  Radio  Amaiieur  License  Manual    $  1,50 

AR.R.L.  Antennj  Book 5  4.00 


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Ameco  Cornrr>eroal  Opefator  Theorv  Count ...  $  S.95 

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73 
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*?6FM  Repeater  Atlas 
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»--*■■ 


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MAIN  ST. 


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TUFTS 


^adio  E 


386  Mam  St.,  Medford   MA   02155 
Phooe:  617  305  8280 


All    styles  of  Speed-X^M  Telegraph   Keys  «r*  Gon- 
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310-001  -  Slack  wrinkle  base,  no  switch,  56  65 
310-033  -  Black  wrinkle  base  with  switch,  S8.20 


600  Hz  CW  Fjlter 
FM  Filter 
Speaker 


&  gA  ■  / 


Model  SSK-1  Features:  extra-long  form-fitting  molded 
paddies  with  adjuaiabie  spring  tension  .  .  adjustable 
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Heavy  die  cast  base  with  non-skid  feat.  Base  and  dual 
cover  black-crackle  finished.   $23.95 

Shipping  weight,  2V*  pounds 


FT  301 
FT  301 
F*301 
FP301 
FRG-7 
QTR2* 

FT  101E 

160-10M 

FT-101EE 

160-1QM 

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Gmvif  Cov  5vn;hror«d  ti*ctTW 

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199  00 

39  DO 

30  00 

749 


XGVR  W/O  Processor        659 


SSK-3 


160-10M 

XCVH  W/O  Processor 

AC  Only.  Let*  Mike 

599 

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Linear  Amplifier 

359 

FTV-650B 

6M  Transvflrter 

199 

FTV-250 

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229 

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Eftlernat  VFO 

99 

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19 

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Speaker /Patch 

59 

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Monitor  Scope 

199 

YD-844 

Dvnambc  Base  Mike 

29 

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Cooling  Fan 

19 

MMB-1 

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19 

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RF  Speech  Processor 

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600  Hi  CW  Filter 

45 

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for  FT-101 

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TRANSMITTER 

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RFP401  RF  Speech  Processor 

MONITOR/TEST  EQUIPMENT 

VC-355  30  MH*  Counter 

YC355D  200  MHr  Counter 

YO-100  Monitor  Scope 

YP-1&0  Dummy  Load/ 

Watt  Meter 
VC-601  Digital  Readout 

MO  t  401  series! 
VHF  PM  &  SS8  TRANSCEIVERS 
FT  224  24CH,  2M  FM 

FT-2  Auto  aCH/2M  FM  Scanner 


45 
49 
19 


554 

39 

729 
289 
199 

74 

179 

249 
379 


200R 

Sigmasizer  200CH, 

2M  FM  Synthesizer 

449 

FT-620B 

6M  AM/CW/SSB 

449 

FT-221 

2M  AM/FM/CW/SSB 

679 

Accessories; 

MMB-2 

Mobile  Bracket  (FT2A) 

19 

MMB-3 

Mobile  Bracket  I2O0R) 

19 

MMB-4 

Mobile  Mount 

(FT-G20B,  FT-221) 


19 


FR  101S 

SOLID  STATE.  160- 2M/SW  RCVR 

FR  101   Digital 

SOLID  STATE.  160-2M/SW  RCVR 

Accessories: 

FC-6  6M  Converter 

F&2  2M  Converter 

FM-1  FM  Detector 

—  Aux/SW  Crystals 

XF-30B  AM-WideFiEter 


499 
659 

30 
40 
20 
5 
45 


FT- 101 E  TRANSCEIVER 


Model  SSK-3  Same  as  SSK-1.  but  mounted  on  a 
solid  mfltal  sub- base  which  is  drilled  and  tapped  to 
mount  your  choice  o-  any  sianoaro  NYE  VIKING 
SPEED*X"  key,  (Id  be  ordered  separately  )  S26  95 

Shipping  weight.  2V*  pounds 


CODE  PRACTICE  SET 

404*002 


31Q-G03 


Model  114-404-002  consists  of  one  standard 
transmitting  key  (Model  1 14-310-001),  linear  cir- 
cuit oscillator  and  amplifier  with  built-in  2" 
speaker,  ail  mounted  on  a  heavy  duty  aluminum 
t?ase  with  non-skid  feet.  Operates  on  standard 
9V  transistor  type  battery  (not  included)   S1B.50 

Shipping  weight,  114  pounds 

Units  may  be  connected  In  parallel  so  that  two 

or  more  operators  can  practice  sending  end  re- 
ceiving to  each  other,  Model  114-404-001  con- 
sists of  amplifier  and  speaker  assembly  only, 
for  use  with  any  NYE  VI  KING  key. 

Shipping  weight  V»  pound 


322-001 

Model  320-001  -  Black  wrinkle  base  S8.65 

Model   320-003    -   Btsck  wrinkle  base  with  switch 

S9.45 

Modal    322-001    -    Black   wrinkle   base  with   brass 

hardware  $8.65 

Modet    322-003    -    Black   wrinkle    base   with   brass 

hardware  with  switch  $10.30 

Model  300011  -  Black  Bakelite  base  vV/MFG  Screws 

for  any  $1  above  Keys  SI. 4 5 


139 


The  Latest  in  Counters 


-  -  an  inexpensive  modularized  50  MHz  system 


Geoffry  W.  Kufchak  WAWFE 
869  Reed  Ave, 
Akron  OH  44Z06 


* II* 


I  finally  decided  I  needed  a 
relatively  simple  but 
effective  counter.  It  had  to  be 
easy  to  build  and  it  had  to  be 
able  to  count  to  50  MHz 
without  using  a  prescaler. 
After  giving  the  design 
approach  considerable 
thought,  i  decided  on  the 
plug-in  board  method.  Then  I 
proceeded  to  break  up  the 
total  circuit  into  the  in- 
dividual circuits  that  make  up 
a  frequency  counter  and 
design  PC  boards  for  each  of 
them.  Counter  circuits  are 
pretty  basic  and  there  arc 
only  so  many  ways  to  design 
one,  so  this  one  may  look  a 
lot  like  others.  I  did,  how- 
ever, add  a  few  ideas  of  my 
own. 


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One  of  the  worst  features 
of  any  counter  is  the  awful 
current  drain  that  the  LEDs 
in  the  display  manage  to  con- 
sume. Even  with  current- 
limiting  resistors,  8  digits  at 
20  mils  per  segment  can  pull 
1,12  Amps.  I  got  around  this 
by  scanning  the  display  so 
that  only  one  LED  is  on  at  a 
time,  This  reduces  current 
consumption  by  one  eighth.  I 
also  decided  to  get  rid  of  that 
ridiculous  number  of  re- 
sistors, since  scanning  the 
LEDs  g^ve  me  a  10%  duty 
cycle.  This  meant  that  the 
average  current  through  the 
LEDs  would  be  10%  of  the 
maximum  current  without 
resistors-  Checking  the  specs 
for    the    LEDs    I    was    using 


(MANS)  showed  that  at  5 
volts  the  maximum  current 
per  segment  would  be  192 
mils  {OUCH!}.  But  10%  of 
that  is  19,2  mils  and  is  within 
the  maximum  of  40  for  the 
LED.  The  maximum  current 
drain  is  now  reduced  to  1 34.4 
mils  when  the  display  is 
showing  an  8. 

Another  change  I  made  is 
the  use  of  a  74LS90  as  the 
first  counter  in  the  chain.  The 
74LS90  is  pin  replaceable  for 
the  7490  and  will  count  in 
excess  of  50  MHz.  Some 
designs  use  the  74196,  which 
uses  inverted  logic  as  com- 
pared to  the  7490.  The 
74LS90  uses  the  same  logic 
so  board  design  is  simplified. 

I  also  added  the  option  of 


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F/#.  J,  Decimal  Counter  Unit 


selectable  gates,   .01    sec,    .1 
sec,  1  sec,  and  1 0  sec. 

Breaking  the  counter 
down  into  individual  boards, 
there  Is  the  Time  Base  Oscil- 
lator and  Divider  (TBOD), 
Display  Scan  Unit  (DSU), 
Decimal  Counter  Unit  (DCU), 
Gate  Control  Unit  (GCU), 
and  Preamp.  AH  these  units 
plug  into  a  master  board 
which  has  all  the  intercon- 
necting circuit  paths  etched 
into  it. 

Approximate  cost,  less 
cabinet,  is  about  $85.00  using 
al!  new  parts,  less  if  you  have 
a  well-stocked  junk  box  and 
can  make  the  boards  yourself. 

Timebase     Oscillator     and 
Divider 

The  TBOD  is  constructed 
on  a  PC  board  that  is  3,5"  by 
T\  Due  to  the  compactness 
of  the  circuit  ft  was  necessary 
to  use  jumpers  for  the  fre- 
quency outputs,  A  double- 
sided  board  could  be  made 
and  eliminate  that  need,  but 
in  the  effort  for  simplicity  I 
decided  against  it.  The  TBOD 
consists  of  a  7400  NAND 
gate  for  the  oscillator  and  a 
series  of  7490s  wired  to 
divide  by  10  in  the  bi-quinary 
mode.  This  method  gives  a 
symmetrical  square  wave  at 
the  output,  needed  for  proper 
gate  timing.  Also,  the  divide 
by  5  signal  is  brought  to  the 
edge  of  the  board,  as  these 
frequencies  are  also  needed. 
1000  Hz  is  also  used  by  the 
Display  Scan  Unit,  so  it  has 
two  outputs. 

I  was  curious  as  to  the 
stability  of  this  circuit,  since 
the  crystal  I'm  using  only  has 
a  tolerance  of  .005%,  so  I 
checked  it  a^insl  a  1  MHz 
signal  with  a  known  accuracy 


of  1  x  10"9.  1  was  quite 
surprised  to  find  that  it  was 
as  good  as  1  x  10~8  after  a 
one  hour  warm  up,  and  held 
its  accuracy  hours  later. 

Provision  has  also  been 
made  for  bringing  the  1  MH* 
signal  out  to  the  back  panel 
of  the  counter  for  checking  it 
against  another  signal. 

This  is  also  the  most  ex- 
pensive of  the  units,  costing 
about  $15.00  with  alt  new 
parts. 

Display  Scan  Unit 

The  DSU  is  also  built  on  a 
3.5"  by  2"  PC  board.  The 
DSU  has  a  7492  divide  by 
twelve  counter  wired  to  reset 
to  0  at  the  count  of  ten. 
The  BCD  outputs  of  the  7492 
are  connected  to  the  BCD 
inputs  of  a  7442  decimal 
decoder,  which  is  used  to 
scan  the  display  LEDs  by 
switching  the  Vcc  on  and  off 
through  a  PNP  switching  tran- 
sistor. The  emitters  of  the 
transistors  are  connected  to 
positive  5  volts  and  the 
collectors  are  routed  to  the 
anodes  of  the  LED  display. 
Pull-up  resistors  are  used  to 
keep  the  transistors  biased 
off,  along  with  current 
limiting  resistors  on  the  bases. 
If  5  volts  does  not  provide 
enough  brilliance  from  the 
LEDs,  a  slight  modification 
on  the  board  will  enable  you 
to  use  a  higher  voltage  for 
switching  to  the  display.  Try 
not  to  use  more  than  10 
volts,  however.  More  than 
that  and  the  LEDs  may  burn 
out. 

The  outputs  of  the  7442 
are  active  low.  That  is,  the 
output  selected  is  at  ground 
and  all  others  are  high. 
Grounding  the  base  of  a  PNP 
transistor    turns    it    on    and 


*■  RESET  0 


fROtf  GATE 
SELECT  SWITCH 


STROBE 


(UtE 


COUNT 


--:---,■  = 


Fig.  4<  Gate  Control  Unit. 


switches  Vcc  to  the  proper 
LED.  Because  the  7492  is 
wired  to  divide  by  ten,  the 
scan  rate  figures  out  to  100 
Hz.  This  is  fast  enough  to 
eliminate  any  flickering,  but 
allows  enough  brilliance  for 
normal  room  lighting. 

With  all  new  parts,  the 
DSU  costs  about  $6.25. 

Decimal  Counter  Unit 

The  DCU  is  constructed 
on  a  3.5 M  by  1.7"  PC  board. 
Except  for  the  first  DCU,  all 
use  standard  7490s  as 
counters.  The  first  DCU  uses 
the  74LS90  by  Fairchild, 
which  was  described  earlier, 
for  a  50  MHz  count  rate. 
Also,  each  DCU  has  a  7475 
quadruple  bistable  latch,  a 
7446  or  7447  BCD  to  seven- 
segment     decoder,     and     a 


socket  for  the  LED.  Any 
Monsanto  LED  may  be  used 
here  as  the  pin-outs  for  most 
of  them  are  identical.  I  used 
the  MANS,  which  is  yellow, 
simply  because  I  had  them. 
However,  the  large  .6"  MAN6 
or  the  .27"  MAN7  will  also 
plug  in.  Both  of  these  are  red. 

For  the  LED  socket,  use 
the  already  preformed  side 
mount  socket  or  be  cheap 
and  bend  the  leads  of  a  wire- 
wrap  socket  like  I  did. 

The     7475     is     used     so 

transfer     the     accumulated 

count   of  the   7490s   to   the 

display  when  strobed  by  the 

Gate   Control    Unit.   A   logic 

one   is  needed  on  the  clock 

inputs  to  transfer  the  input 

nformation.  When  the  clock 

s  low,  the  latch  will  store  the 

nformation    until    the    next 


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strobe  pulse.  If  the  input  has 
not  changed,  the  output 
won't  either.  If  new  informa- 
tion is  present  at  the  input, 
the  outputs  will  change  to 
agree  with  the  inputs. 

The  outputs  of  the  7475 
are  connected  to  the  inputs 
of  the  7447  which  decodes 
the  BCD  to  the  proper  coding 
to  display  the  corresponding 
decimal  number  on  a  seven- 
segment  readout. 

Four  of  the  DCUs  have 
provision  for  using  the 
decimal  point  so  that  the 
display  can  be  wired  to  show 
the  frequency  in  either  kHz 
or  MHz.  One  need  only  wire 
the  proper  decimal  point  to 
ground  through  the  gate 
select  switch. 

The  cost  of  the  DCU  will 
be  about  $6.50  for  the  50 
MHz  version,  and  a  little  less 
than  $6.00  for  the  standard 
version* 


Gate  Control  Unit 

The  original  circuit  l  tried 
for  this  was  unsatisfactory,  as 
the  time  needed  for  the 
strobe  and  reset  0  pulses  was 
equal  to  the  gate  time.  On  the 
faster  gates  this  was  no  prob- 
lem, but  on  a  10  second  gate 
it  could  be  annoying  having 
to  wait  20  seconds  for 
updating  the  display.  So  I 
redesigned  it  with  the  basic 
idea  that  1  wanted  a  10 
second  gate  and  the  resets  to 
occur  within  one  second.  A 
look  at  the  timing  diagram 
may  help  in  understanding 
the  operation  of  this  circuit. 
Refer  to  the  schematic  for 
lettered  lines.  Note  also  that 
the  board  has  a  gate  LED 
incorporated  on  it,  elimin- 
ating the  need  to  front  panel 
mount  one.  It  will  show 
through  the  display  window 
to  the  right  of  the  digits. 

The  GCU  is  built  on  a  3.5" 


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by  1.7"  PC  board.  It  consists 
of  four  ICs:  a  7492,  divide  by 
twelve;  a  7410,  triple-three 
input  NAND  gate;  a  7402, 
quadruple  two-input  NOR 
gate;  and  a  74LS0Q,  chosen 
also  for  the  high  toggle  speed. 
Let  us  assume  we  have 
selected  a  10  second  gate. 
Through  the  gate  select 
switch,  1  Hz  and  2  Hz  signals 
are  routed  to  the  inputs  of 
the  GCU,  One  gate  of  the 
74LS00  is  used  to  invert  the 
1  Hz  and  apply  it  to  the  clock 
input  of  the  7492,  Normally 
this  IC  would  count  to  twelve 
and  reset  to  0,  but  with  the 
7410  gate  connected  to  the 
A,  C,  and  D  outputs,  it  will 
be  forced  to  reset  at  the 
count  of  eleven.  Zero 
detecting  the  outputs  with  a 
NOR  gate  and  NAND  gate 
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T^  &  50  MWz  Frequency  Counter. 


high  for  10  seconds  and  low 
for  one  second,  which  is  the 
time  between  reset  and  the 
next  input  cycle.  Another 
gate  of  the  74LS00  is  used  to 
invert  this  pulse. 

By  combining  the  inverted 
gate  pulse  with  the  1  Hz  and 
2  Hz  signals,  and  then  in- 
verting the  outputs  of  the 
other  two  gates  of  the  741 G, 
the  Strobe  and  Reset  0  pulses 
are  generated  and  transferred 
to  the  rest  of  the  counter, 
Through  trial  and  error  it  was 
found  that  there  had  to  be  a 
minimum  amount  of  time 
between  the  two  pulses  and 
this  circuit  provides  it.  Unfor- 
tunately, due  to  the  mini- 
mum pulse  width  needed  to 
reset  the  7490s  in  the  counter 
(50  nsec)>  the  fastest  gate 
time  allowable  is  ,001  second. 
This  is  probably  faster  than 
needed  anyway. 

The  current  limiting  re- 
sistor for  the  LED  should  be 
chosen  for  the  particular  LED 
being  used.  Generally,  about 
180  Ohms  should  be  right. 
Any  color  may  be  used;  I 
used  yellow  to  match  the 
display. 

This  is  also  the  cheapest 
unit,  costing  about  $4.00 
with  all  new  parts. 

The  Preamp 

I  finally  found  a  Preamp 
circuit  that  would  work,  I 
had  tried  several  others  that 
had  been  published,  but  had 
terrible  sensitivity.  This  one  I 
discovered  while  reading  back 
issues  of  73,  It  is  from  the 
''Latest  K20AW  Counter 
Update"  in  the  May,  1975 
issue  by  W82UKP.  Some 
minor  changes  were  made, 
though.  I  used  a  74LS04  to 
obtain  a  50  MHz  working 
speed,  a  2N708  for  Q2,  and  a 


142 


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shipping.  Indiana  residents  add  4%  sales  tax. 
Crystals  for  246.94  MHz.  39S.  Ali  olhet  freq- 
7. 10. 

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412  North  Wei n bach  Ave, 
Evans'wille,  Indiana  4771  1 
812  476  2121 


ECM 


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197S  World  Radio  TV  Handbook  -  $10. % 

Gated  1000/100/50/25/10  kHz  Calibrator  -  $54.00 

Barlow  Wad  ley  &  R.L.  Drake  Receivers 

1976  "Confidential^  Frequency  List  -  55.45 

GILFER,  Box  239,  Park  Ridge,  N  J  07656 


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a  digital 
frequency 
counter  you 
can  count  on 


New  300/600  Mhz  Digital  Frequency  Counters  are  in  a  class  by  them- 
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10  Mhz  crystal  oscillator 

10ppm    25    to    40    C 
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Mhz 

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Mhz 

0.1        second        gate 
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120    VAC    25    Watts 
12     VDC* 
8"  x  8"  x  21/2" 


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143 


Fig.  9(a).  TBOD  board  (full  size). 


Fig.  1 0(a).  DSU  board  (fa/1  size). 


slightly  different  input 
scheme.  Finally,  sensitivity 
became  livable.  A  scope  and 
rf  signal  generator  (HP  608D) 
showed  a  sensitivity  of  10 
mV  from  10  MHz  on  up.  At 
audio  frequencies,  about  50 
mV  was  needed  for  reliable 
operation. 

The  reason  for  all  that 
extra  space  on  the  board  lay- 
out is  that  I  hope  to,  in  the 
future,  incorporate  an  on- 
board prescaler  using  the 
11C90  by  Fairchild,  Pro- 
vided, of  course,  that  the 
circuitry  is  as  simple  as  that 
using  a  95H90.  With  the 
11C90,  the  counter  should 
operate  in  excess  of  500  MHz. 

Power  Supply 

Due  to  the  heavy  current 
demand,  about  1 .3  Amps,  I 
decided  on  the  circuit  shown 
to  regulate  the  five  volt  line, 
rather  than  use  two  LM309s, 
All  components  can  be 
mounted  on  the  rear  panel 
with  appropriate  mounting 
hardware  and  solder  lugs. 
Heatsink  the  pass  transistor 
and  LM309K,  You  can  use  a 
bridge  rectifier  module  or 
individual  diodes.  They 
should  be  rated  for  at  least  5 
Amps  at  50  volts.  The  trans- 
former is  a  12.6  V  ac  at  3 
Amps,  or  parallel  two  smaller 
rated  ones.  Use  a  2N3055  for 
the  pass  transistor  or  a 
suitable  substitute  with 
similar  ratings.  The  neon  pilot 
Sight  is  not  really  needed,  but 
I  like  little  frills  to  dress  up  a 
front  panel. 

The  fuses  should  be  of  the 
fast  blow  type.  Fuse  holders 
mounted  on  the  rear  panel  is 
the    best    method,   but   they 


can  be  soldered  in  inside  the 
chassis.  The  power  switch  can 
be  eliminated  so  that  the 
counter  is  on  whenever  the 
line  cord  is  plugged  in. 

General  Construction  and 
Testing 

After  etching  and  drilling 
all  the  boards,  install  the 
jumpers  first  because  two  on 
the  GCU  are  under  ICs,  Next 
put  in  the  resistors  and  capac- 
itors, and  then  the  transistors 
and  ICs.  The  LED  sockets  on 


the  DC  Us  come  next;  then 
install  the  LEDs.  Install  the 
sockets  on  the  master  board* 
Wire  the  power  supply  in 
the  case,  along  with  the  front 
and  rear  connectors  and 
switches.  Secure  the  master 
board  to  the  case  with  small 
angle  brackets,  at  least  4 
inches  behind  the  front  panel. 
This  will  allow  the  boards  to 
be  installed  and  removed 
easily.  Or  the  master  board 
may  be  hinged  at  the  bottom 
to  tilt  back.  Next  do  the  main 


wiring  from  the  power  supply 
to  the  master  board  and  the 
front  panel  switches.  Use 
RG-174  for  the  counter  input 
and  the  1  MHz  test  output. 
Location  of  the  controls  and 
cutouts  is  entirely  up  to  the 
builder  and  depends  on  the 
case  used. 

Before  installing  any 
boards,  check  the  power 
supply  for  proper  operation. 
If  it's  working,  turn  the 
power  off  and  install  the 
TBOD     in     the     12-contact 


Fig.  9(b).  TBOD  component  layout.  Use  jumpers  to  bring  frequency  outputs  to  edge.  1  board 
per  counter.  Dot  indicates  pin  h 


Fig,  10(b).  DSU  component  layout  1  board  per  counter.  Dot  indicates  pin  /< 


144 


Fig.  7  /  (a).  DCU  board  (full  size). 


Fig,  12(a).  GCU  board  (full  size). 


socket  on  the  left  (from  the 
front  of  the  counter).  An 
accurate  frequency  counter 
will  be  needed  to  set  the  1 
MHz  oscillator  at  least  1  x 
10"8.  Turn  the  power  on  and 
with  the  counter  connected 
to  the  1  MHz  test  output, 
adjust  the  trimmer  to  read  1 
MHz,  plus  or  minus  a  few 
Hertz,  If  it  won't  adjust,  try 
another  7400,  This  is  an 
initial  adjustment.  After  the 
rest  of  the  boards  are  in- 
stalled, and  at  feast  a  one 
hour  warmup  period,  recheck 
the  frequency.  Before  turning 
off  the  power,  check  the 
divider  chain  for  proper  fre- 
quency outputs.  If  everything 


checks  out,  turn  the  power 
off  and  install  the  GCU 
board.  Select  the  one  second 
gate  and  turn  the  power  on. 
If  the  GCU  is  working,  the 
gate  LED  will  blink  on  for 
one  second  and  off  for  10 
msec,  Check  the  Reset  0  and 
Strobe  outputs  with  a  scope 
for  a  10  msec  putse.  If  the 
GCU  checks  out,  turn  the 
power  off  and  install  the  DSU 
board. 

Turn  the  power  on  and 
check  each  of  the  DSU 
outputs  with  a  scope  for 
proper  switching.  A  fre- 
quency of  125  Hz  should  be 
measured.  If  the  DSU  is 
working,  turn  off  the  power 


LEO  VCC  SCAN 
STROBE 

CLOCK 

RESET  "0" 
CARRY 
VCC 

GROUND 
D.P  CATHODE 
NC 
NC 


and  install  the  DCUs.  Turn  on 
the  power  and  check  that  the 
display  reads  all  0s.  If  not, 
make  sure  all  the  boards  are 
in  the  sockets  tight  or  check 
for  unsoldered  connections, 
or  bad  ICs.  If  all  0s  are 
displayed,  turn  off  the  power. 
Install  the  Preamp  board 
and  turn  the  power  on.  The 
display  should  still  read  all  Os. 
If  not,  the  DSU  may  need 
bypass  capacitors  on  the  Vcc 
line  on  the  master  board.  Any 
signal  on  the  Vcc  line  greater 
than  about  20  mV  will  trigger 
the  Preamp  and  cause  false 
counting  with  no  input.  Any 
input  signal  will  have  to 
exceed  this  by  at  least  1 0  mV 


if 

7447 

LEO 


^^^■■■iM 


J 


Fig.  11(b),  DCU  component  layout.  Use  side  mount  socket  for  LED  (see  text).  One  DCU  uses 
74LS90  for  50  MHz  count  speed.  6  or  8  boards  per  counter  Dot  indicates  pin  h 


GATE  IN  B 
STROBE   OUT 
COUNT  OUT 
RESET  "0" 
NC 
VCC 
GR 0UNC 
FROM  PREAMP 
GROUND 
GATE  IN  A 


o    2N708 


Fig.  12(b).  GCU  component  layout.  Use  sleeving  to  insulate  resistor  lead,  1  board  per  counter. 
Dot  indicates  pin  L 


to  be  counted.  This  has  been 
one  of  my  headaches  with  my 
counter,  although  I  know  I 
have  a  bad  7442  in  the  DSU 
which  is  causing  the  problem. 

If  you  get  all  0s  on  the 
display,  proceed  to  check  out 
the  whole  counter  by  using  a 
signal  generator  to  check  the 
frequency  response  and  sensi- 
tivity. You  may  want  to  keep 
a  graph  or  record  of  the 
results  for  future  reference. 
My  counter  showed  a  sensi- 
tivity of  50  mV  from  10  Hz 
to  about  35  kHz,  and  from 
10  MHz  on  up,  about  10  to 
1  5  mV,  I  didn't  have  any  way 
to  check  the  frequencies  in 
the  middle* 

All  that's  left  to  do  is 
recheck  the  TBOD  frequency 
and  button  up. 

Troubleshooting 

If  you  run  into  difficulty 
getting  the  oscillator  to  zero 
on  exactly  1,000  MHz,  try 
another  7400.  Some  will 
oscillate  better  than  others.  It 
has  something  to  do  with  the 
characteristics  of  different 
batches.  You  can  use  a  scope 
or  another  counter  to  check 
the  divider  chain  for  proper 
division.  On  the  GCU,  a  dual- 
trace  scope  is  nice  because 
you  can  check  and  compare 
the  waveforms  at  more  than 
one  point  and  reference  them 
to  another.  Most  problems 
here  are  caused  by  loose  ICs 
in  the  socket  —  for  me,  any- 
way. Actually,  most  problems 
can  be  cured  simply  by  trying 
a  different  IC.  If  you  still  run 
into  difficulty,  look  for 
solder  bridges,  bad  connect- 
ions, wiring  errors,  or  even 
the  possibility  of  a  leaky  or 
bad  transistor.  Well,  what 
more    can    I   say?   Have  fun 


145 


Fig.  13(a).  Preamp  board  (full  size). 


counting! 


Afterthought 

One  can  save  in  construc- 
tion costs  by  not  using 
sockets  for  the  ICs,  although 

it's  a  good  idea  to  make 
certain  the  IC  is  good  first. 
It's  not  fun  unsoldering  them. 
Do  use  sockets  for  the  LEDs, 
though.  The  preformed  side 
mount  ones  are  bestj  but  a 
wire-wrap  socket  will  do  just 
as  well  if  you  carefully  bend 
the  leads  with  needlenose 
pliers. 

Try  for  a  trade-off 
between  price  and  visibility 
on   the  display.    Sure,   those 


large  .6M  LEDs  are  easy  to 
read,  but  expensive.  The 
cheaper,  .27"  ones  will  work 
just  as  well,  and  they  can  be 
had  in  different  colors:  red, 
green,  yellow,  or  even  orange. 
Check  the  ads  in  the  back  of 
73  and  I'm  sure  you'll  find 
something. 

The  Amphenol  PC  card 
sockets  are  available  from 
Cramer  International, 
Newton,  Mass.,  or  the  local 
office  in  your  area. 

The  cabinet  will  have  to  be 
at  least  W  high  J  OK"  long, 
and  7"  deep.  Make  sure  you 
leave  at  least  ViM  between  the 
LEDs  and  the   back  of  the 


Fig.  1 4,  Master  board  (full  size). 


Parts  List  for  Frequency  Counter 

TBOD 

1 

,1  uF  Disc 

1 

7400 

1 

.22  uF  Disc 

7 

7490 

1 

1 N4001 

1 

PC  Edge  Connector 

DSU 

Ampheno!  #143-012-03 

1 

7492 

8 

14  Pin  DIP  Sockets 

1 

7442 

2 

680  Ohm  V*  Watt 

1 

PC  Edge  Connector 

1 

150  Ohm1/*  Watt 

Amphenol  Fl  43-01 2-03 

1 

35  -  20  pF  Variable 

1 

14  Pin  DIP  Socket 

E.  F.  Johnson  #274-0020-005 

1 

16  Pin  DIP  Socket 

1 

.005  uF  Disc 

8 

470  Ohm  %  Watt 

1 

1 .000000  MHz  Crystal 

8 

2.2k  %  Watt 

1 

PC  Board 

8 

2N3906  PNP  Transistors 

1 

PC  Board 

DCU 

1 

74LS90  (50  MHz  Version  I 

GCU 

7 

7490 

1 

74LS00 

8 

7475 

1 

7402 

8 

7446  or  7447 

1 

7410 

8 

PC  Edge  Connectors 

1 

7492 

Amphenol  #143-010-03 

1 

PC  Edge  Connector 

8 

Seven- Segment  LEDs  (See  Text) 

Amphenol  sri  43-01 0-03 

8 

14  Pin  DIP  Sockets 

* 

14  Pin  DIP  Sockets 

8 

14  Pin  Wire  Wrap  Sockets 

1 

470  Ohm  %  Watt 

16  16  Pin  DIP  Sockets 

1 

3,3k  y*Watt 

8 

PC  Boards 

1 

2N7G8  MPN  Transistor 

1 

LED 

Power  Supply 

1 

#180  Ohm  1/«  Watt 

1 

12,6  V  ac,  3  Amp  Transformer 

1 

PC  Board 

1 

50  V,  5  Amp  Bridge  Rect. 

1 

2N3055 

Miscellaneous 

1 

LM309K 

Gate  select  switch,  BNC 

1 

100uF,25  V 

connectors,  plastic  window, 

1 

1000  uF,  10  V 

fuse  holders,  hardware,  knobs. 

1 

,01  uF  Disc 

cabinet,  etc. 

146 


r 


71 


VCC  +5 

GROUND 

F  OUT    TTL 

F  IN  >IOmV 


MPFi02     2N^08 


74LS04 


68pF 


IN9I4 


J 


Fig*    13(h).    Preamp   component  layout.    Resistors  are  V4    Watt.    R5}   R6t   Rl  are  mounted 
vertically.  I  board  per  counter,  Dot  indicates  pin  7. 

front  panel  for  removal  of  the  If   you    don't   need   more      switch  and  hardware  the  cir- 

plug-in  cards.  than  one  gate,  eliminate  the      cult  The  switch   I  used  is  a 


four-pole,  five- position,  non- 
shorting  miniature  rotary, 
Centralab  #P5-11.  The  extra 
position  and  pole  made  it 
possible  to  turn  the  power  on 
when  selecting  the  timehase. 

Also,  since  I  used  a  new 
GCU,  I  found  that  I  could 
eliminate  the  last  7490  in  the 
TBOD.  Or  leave  it  in  if  you 
want  an  accurate  ,1  Hz  signal 
for  something. 

1  had  a  lot  of  fun  designing 
the  counter,  but  it  was  not 
without  its  headaches.  I'm 
just  happy  it  works,  ■ 


Y&U  JLSKM3M* 

JFOJF*  IT  1 

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Write  or  call  for  complete  information.  Send  check 
or  money  order  for  $132.00  plus  $1.50  for 
shipping.  Indiana  residents  add  4%  sates  tax. 
Crystals  for   146,94  MHz.    3  95,  All  olher  freq. 

7  10  

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412  Worth  Weinbach  Ave. 

Evansvifk,  Indiana  47711 

812-476-2121 


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An  easy-tobuNd  50rnHz  (6-digit) 
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Standard  easy-to-find  parts,  too!  {Unlike 
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Provof  UT  84601  (801)  375-8566 


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40  Amp  Stud  Htctrfttt.  200  Volt 

Meter  Sentry  proiecti  mew  mortmenti 


RF  DEVICES 

2W3375    3W4O0MH1-  .    SbbO 

7N386G     )W400Wn.  99 

2N5&88    3W  175  MHjj  4  75 

7NS5SQ  1MWSMH:  7  80 

2NSsai  2sw  175  wm/  io« 


2N6060    4Wl7SMHr  S5.40 

ztmes  saw  t  ts  mh/  1095 

77*6063  3CMT  1 75  MHz  12  30 

2N6064  40W  1 7S  MHl  16  30 


HEAVY  OlfTV  REeTlHERj 

700  Volt  TOO  Amp  008  SUO 

200  Volt  250  Amp  DOfl  12  93 

1000  Vatt  2  Amp  SI-COft  ffectitar  RCA  10  for  .99 

10,000  Voll  Silicon  R«cllti*r  In*   65  mA  2.95 

A  ID  EL  DO  KITS 
Digital  Cluck  Kit    Humi  M.nuiti  &  Setondi  Lajge  hall  inch  LED 

ittdcutL   Etyued  timi  indicator    12  hour  lpim«t  with  24  hour 

itaim   Snooze  twiuf*.  AM   PM   indicalrjr,   power  wjifrty,  power 

failure  indicator .  Complttf  with  wood  grain  cabinet  $23  35 

MOS  Tim.  tW  Kit  50/50  He  5.95 


FND503  Coninuin  C^ihodd 

FND  SO/  Comniun  Allude 

FND35S 

MAN  5  Green 

QL  747  Cam  marl  Anode 


DISPLAY  LEOS 


500 

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3  ,., 
,27 
6 


DISCRETE  iEDS 
Jumbo  Reds,  lung  m  ihoit  bulb 
Jumbo  Orange,  Grnn,  Clear  Rnti  ur  Omen  . 
ZQSSanes.  Green,  Qimiiji!.  VeHowor  Red  , , 
RLZur.  Micq  fled 


$175 
175 

1.35 

t  46 
2,25 

.GIwSl.QO 
5  far  $1  00 
5  lor  SI. 00 

.5rar  S1.0O 


ZEWERS 

IN 745  to  TN769  400  Mw  ka  .25 


1N4728ia  1N4764  I  w 


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MJE340  r2N&65&)  ,  , . 

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565  Tiriter  .  . 

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200  Volt  25  An iej  BndQi?  .     1.60 

INS  14     1N414G 

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1M34     IWbfJ     1NB4 

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CA302BADif    Amu. 
LM301  Op  Amp 

LM309K  Voli  Hug 
LM3B0M  Audio  Arup 
NE&40L  Power  Orl^r 
NE&S1BPLL 
N£5&7BPLL  .. 

NE-.bfc&APLL 

LM709MinDIPOp  Amp 
LM741  CE  T0&  Op  Amp    r 
14  qr  16  Pm  IC  Socket!     . 
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2H22A& 

2N2219A 

2NZ222A 

2N2369   , 

2N24B3    . 

2N2484   . 

2N2905 

2N7907 

2N2925G 

2N2926Y 

7N3053 

2N3438 

2N3439 

2N3440 

2M3&12 

2M3553 

2K3563 

2K3584 

2K3638 

2K3646 

2N3713 


2K377I 


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2N3B40 
2N3859 
2N3903 
2N3906 
2N3924 
2N3920 
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2N440I 
2N4402 
2N4403 
2N4409 
2N4427 
2N4429 
2N488B 
2N5016 
2N5090 
2N5129 
7N5175 
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750 

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1  70 

is  USA  Mai 


2281 A  Babylon  Tnpk  M«rrickf  N.Y.  T1566 
(516)  378-4555 


ATTENTION  USERS  OF 
VHF  SCANNING  RECEIVERS 


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receivers  wiih  the  crystal  formula  Fc  = 
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For  complete  details  of  this  synthe* 
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J 


148 


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73  MAGAZINE  •  PETERBOROUGH  NH  03458 


149 


Why  wan  any  longer  for  a  rig  that  offers  top  performance,  dependability 
and  versatility    .    the  TS-520  has  proven  itself  in  the  shacks  of 

thousands  of  discriminating  amateurs,  in  field  day  sites,  in  DX  and 

contest  stations,  and  in  countless  mobile  installations. 
Superb  craftsmanship  is  evident  throughout    ,  ,  in  its  engineering 
concepts  as  well  as  its  construction  and  styling  .  .  .  craftsmanship  that 
is  a  Kenwood  hallmark. 

Maybe  the  Kenwood  TS-520  is  the  one  you  have  been  waiting  for. 

Kenwood  offers  accessories  guar- 
anteed to  add  to  the  pleasure  of 
owning  the  TS-520,  The  TV-502 
transverter  puts  you  on  2-meters 
the  easy  way  (lis  completely 
compatible  with  the  TS-520) 
Simply  plug  it  in  and  you're  on 
the  air  Two  more  unrts  designed 
to  match  the  TS-520  are  the  VFO- 
520  external  VFO  and  the  model 
SP-5  20  external  speaker.  All  with 
Kenwood  quality  built  in. 

"MM" BUERGER 


TS-520 

pacifications 


MODES:  USB  LSB,  CW 

POWER-  ZOO  watts  PEP  input  on  SSB,  160  watts 
DC  input  on  CW 

ANTENNA  IMPEDANCE:  50-75  Ohms, 
unbalanced 

CARRIER  SUPPRESS! ON:. Better  than  -45  dB 

UNWANTED  SIDEBAND  SUPPRESSION'  Belter 

than  -40  dB 
HARMONIC  RADIATION.  Better  than  -40  dB 
AF  RESPONSE:  400  to  2600  Hi  (-6  dB) 
AUDIO  INPUT  SENSITIVITY-  0.25|uVfor  10  dB 

(S+N)/N 

SELECTIVITY:  SSB  2.4  kHz  (-6  dB)  4.4  hHr 
(-60  dB)  CW  0.5  kHz  (-6  dB). J. 5  kHi 
(-60  dB)  (with  accessory  filter) 

FREQUENCY  STABILITY:  100  Hz. per  30 

minutes  alter  warm  up 
IMAGE  RATIO:  Better  than  50  dB 
IF  REJECTION:  Better  than  50  dB 
TUBE  &  SEMICONDUCTOR  COMPLEMENT 

3  tubes  (2  a  614GB.  12BY7AK  1  IC,  IB 

FETr44  transistors,  84  diodes 
DIMENSIONS:  13.1"  W  *  5.9,r  H  x  13.2"  D 
WEIGHT  35.2  \b$. 
SUGGESTED  PRICE:  $629,00 


VFO-520 


Provides  high  stability  with  precision  gearing. 
Function  switch  provides  any  combination  with 
the  TS-520.  Both  are  equipped  with  VFO  indi- 
cators showing  at  a  glance  which  VFO  ss  being 
used  Connects  with  a  single  cable  and  obtains 
its  power  from  the  TS-520.  Suggested  price 
$115.00, 


SP-520 


Although  the  TS-520  has  a  built-in  speaker,  the 
addition  of  the  SP-520  provides  improved  tonal 
quality.  A  perfecl  match  in  both  design  and 
performance  Suggested  price:  $22.95: 


TV-502 


I RANSMITTING/RECE3VING  FREQUENCY: 

144-145.7  MHz.  145  0- 146,0  MHz  (option), 
INPUT/OUTPUT  IF  FREQUENCY:  28,0-29.7 

MHz 
TYPE  OF  EMISSION:  SSB  (A3JJ.CW  (Al) 
RATED  OUTPUT:  SW  (AC  operation) 
ANTENNA  INPUT/OUTPUT  IMPEDANCE:  SOU 
UNWANTED  RADtATION:  Less  than  -60  dB 
RECEIVING  SENSITIVITY-  More  than-  1«V  at 

S/N  10  dB 
IMAGE  RATIO:  More  than  60  dB 
IF. REJECTION:  More  than  ^0  dB 
FREQUENCY  STABILITY:  Less  than    l  2.5  kHz 

during  1-60  mtn  after  power  switch  is  ON 

and  within  150  Hi  (per  30  min)  thereafter 

POWER  CONSUMPTION:  AC  220/12QV.  Trans- 
mission 50Wmax.,  Reception  12W  max 

DC  13  ev.  Trans- 
mission 2  A  max.,  Reception  0.4A  max 

POWER  REQUIREMENT:  AC  220/120V,  X  12 
16V  (standard  voltage  13. 8V) 

SEMICONDUCTOR-  FET  5.  Transistor  15, 
Diode  10 

DIMENSIONS:  6  V  W  x  6"  H  x  IBW'  D 

WEIGHT:  11.5  lbs. 

SUGGESTED  PRICE:  J249.00 

CW-52Q 

500  Hz  CW  Crystal  Filter:  $45.00. 

Prices  subject  to  change  without  notice 


I 

N 
C- 


AMA  TEUR  RADIO  fS  OUR  BUSINESS 

68  N.  York  Ro\,  Willow  Grove  PA  19090 
Phone;  (215)  659-5900 

CALL  OR  WRITE  FOR  BEST  DEAL 


mflSHw  r.ftgrrjfl 


AMATEUR  SERVICE  PRODUCTS 
-  AMATEUR  HET  PRICING  SUPPLEMENT 


"MM" BUERGER. 


N 


FitqwtfKy 


1006       6WFM 


?MFM 


302      2M  FM 

IDZft 
I2D2B 

1202 
1202C 
#200? 

Am 

•01 

1506    44DMMjtFM 

750ft 

ISO      440MHfFM 

II A   Ȥ10MSSB 


22DMH/FM 


Input 


Output        tektp 
(Nominal? 


Ham  Nt  1 


DRAKE 


1QW 
2W 

tw 

m 
iw 
iw 

l(W 

tow 

IflW 
25W 
10W 
1DW 

taw 
tw 

1W 
IW 

AW 
S-20W 


iWi 

C 

now 

c 

2SW 

A 

45W 

9 

BOW 

c 

120W 

C 

4bW 

A 

BOW 

C 

1Z0W 

c 

100W 

B 

200W 

0 

4BW 

A 

BOW 

G 

35W 

C 

75W 

D 

3SW 

A 

?5W 

0 

400WPEP 

1 

1185  00 
239  00 

S11S  00 
14?  00 
22900 
2B900 

1119.00 
199,00 
239.00 
209  00 
375  00 

SU3.0D 
249,00 

£22900 
41900 
169  W 
379  BO 
395  00 


»  *  *  * 


100.00 
120.00 


s 


$335.00 

Standard 

Communications 


WALKIE  TALKIE 
146  A 

includes  rubber  ducky  antenna, 
N icads  with  charger 
plus  Deluxe  carrying  case 


*  R-4C  RECEIVER ..  599.00 

'#  T-4XC  TRANSMITTER 599.00 

*  TR  4C  TRANSCEIVER  ,  * .  % . « 599.95 

AC  4  POWER  SUPPLY ..........  120.00 

M£4  SPEAKER    ..  .  24.95 

*  SPR  4  RECEIVER . . 629.00 

*  DSR-2  VLF-HF  DIGITAL  RCVR   . , .  .,2,950.00 

TR-22C  FM  TRANSCEIVER 229,95 

4NB  NOISE  BLANKER  R  4C 70.00 

250Hz,  500Hz,  1500Hz  FILTERS  R-4C,  EACH    .  52.00 
34PNB  NOISE  BLANKER  TR-4C  .  . 

R  V-4C  VFO  TR-4C , 

MN*4  ANTENNA  MATCH  80X 1 10.00 

MN2GO0  ANTENNA  MATCH  BOX   .........   220.00 

W-4  WATTMETER  1.8  TO  54MHz .  72.00 

WV-4  WATTMETER  20  TO  200MHz 84.00 

RCS4  REMOTE  CONTROL  ANTENNA 

SWITCH „ . . 1 . . -  1 20,00 

*  L4B  LINEAR  AMPLIFIER    895.00 

*  SSR-1  COMM  RECEIVER ,  350.00 

REGENCY 

HR-2B  FM  2  METER  TRANSCEIVER 229,00 

HR-212  FM  2  METER  TRANSCEIVER 259.00 

HR-220  FM  220  MHz  TRANSCEIVER .  .239.00 

*  HR  440  FM  440  MHz  TRANSCEIVER  .......  .349.00 

HR*6B  FM  6  METER  TRANSCEIVER  ..- 239.00 

AR-2  2METER  LINEAR  AMPLIFIER ...119.00 

P-110  POWER  SUPPLY  117V  to  13.8  DC  5  AMP .  49.95 


TEN-TEC 

^TRITON  tV  TRANSCEIVER  .  .,  699.00 

£.252G  POWER  SUPPLY 99,00 

+  252G  POWER  SUPPLY/VOX     .  .   129.00 

207  AMMETER 14.00 

245  CW  Fl  LTER     ,  .  . 25,00 

215P  MICROPHONE  PTT    ......  27.50 

251   POW£  R  SUPPLY  9  AMP  ....  79.00 

206  CRYSTAL  CALIBRATOR    .  ,  26.95 

208  CW  FILTER 29.00 

KE  Y£R  KfV5A    .  ,  .  -  * .....  38.50 

KE  YER  KR  20A .  67.50 

j£KEYER  KR  SO 110.00 

HUSTLER    RESONATORS 

All  resonators  are  precision  wound  with 
optimized  design  for  each  band,  Assembly 
includes  17  7  PH  stainless  tt«*l  adjustable 
tip  rod  for  lowest  SWR  and  band  edge 
marker.  Choose  for  medium  or  high  power 
operation. 

STAN  DA  ftp   HUSTLER   RESONATORS— 
Pow*f  Rating:  400  watte  SSS 


far  an  Economy  Price? 
THAT'S  RIGHT! 
Introducing  the  EC0N0-LINE 


% 


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Model    Input     Output        Typical  Frequency         Price 

702     5-20W    50-90W    10m/70out    143-149  MHz  $139.00 
702B   1-4W      60-80W    1  in/70  out   143-149  MH*    $169.00 


ASTATIC 
MICROPHONES 


SILVER  EAGLE 


CUSHCRAFT  ANTENNAS 


A50-3 
A5CK5 
A50-6 
A5O-10 


VHF/UHF  BEAMS 


T-UGB-D104,  transistor ned , . $48  GO 


S   27.50 
39.50 

59.50 
89.50 


A 144-7 

A144-11 
A43CM 1 


19.95  #T  UG9-D304,   "Silver  Eagle,"  transistorized 
24.95 


19.95 


UGOI 04.  ceramic  or  crystal 


S54  60 
$4260 


•  • 


AMATEUR  FM  ANTENNAS- 


A147*4 
A 147-11 
A147^20T 
A147  22 
A220-7 
A220-1 1 
A449-6 
A449-1 1 
AFNMD 
AFM-240 


$   15,95  AFM-44D  47,50 

24.95  AR-2  18.50 

47.50  AR-6  24+50 

69.50  AR-25  21.50 

18.95  AR-220  18.50 

22.95  AR-450  18.50 

15.95  ARX-2  28.50 

21.95  ARX*2K  11.95 

53,50  ARX-220  28.50 

49.50  ARX-450  2850 


G  BankAmericard 


Interbank 


QMasterCharge 


Name 


Address 


City 


State 


— 


2ip 


Card  No. 


Expiration  Date 


Signature 


Modal 

Band 

Price 

RM-10 

10  meters 

no  75 

AMIS 

15  meter* 

in  75 

RU-20 

2Q  meters 

112  75 

IthMO 

40  meters 

f15JS 

RU75 

Ti  ^efe'i 

ItfiSS 

RM-8C 

BO  meters 

116  « 

HUSTLER  Mounts,  Leads  &  Acoas*ories 

STAINLESS   STEEL   BALL   MOUNT 
FOR    DECK,   FENDER   OR  ANY 
FLAT  SURFACE 

MODEL  SSM-2 

Heavy  2"  reinforced  stainless  steel 
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I 

N 
C 


RELA?  OUTPUT 


TRANSISTOR  OUTPUT 


B«  « 


*i2  TO  28VOC 


TO«ECE)VER 
AUDIO  STAGE 
l££t  TEJfTl 


r 


LOAD 


Fig.  L  Universal  COR  schematic 


Anybody  building  a  re- 
peater  or  a  remote  base 
needs  a  carrier  operated  relay 
(COR).  A  COR  is  a  usually 
simple  device  that  hooks  into 
an  FM  receiver  and  closes  a 
relay  when  a  carrier  comes  in 
on  the  receiver.  The  relay  can 
be  used  to  activate  a  trans* 
miner  for  repeater  applica- 
tions or  activate  any  of  a 
number  of  other  devices  for 
special  purposes  such  as  tape 
recorders,  meters  or  alarms, 
Presented  here  is  what  1 
believe  to  be  the  simplest 
circuit   for   a   COR    around. 


Unlike  most  other  circuits, 
this  one  will  work  on  any 
receiver,  vacuum  tube  or  solid 
state. 

This  circuit  was  designed 
for  mobile  applications,  I 
wanted  something  simple, 
solid  state,  rugged  and  re- 
liable. The  final  draft  meets 
all  of  these  specifications.  I 
have  two  of  these  circuits  in 
my  car  controlling  an  on- 
board repeater  that  will  relay 
450  MHz  to  146  MHz  and 
vice  versa.  With  the  repeater 
installed  in  my  car  I  am  able 
to  use  a  450  MHz  hand  trans- 


ceiver and  work  back  to  the 
car,  firing  up  my  2  meter 
mobile  with  150  Watts  on 
any  VHF  channel.  This  makes 
the  equivalent  of  a  150  Watt 
HT  with  a  5  dB  antenna.  Ii 
works  real  well,  but  people  I 
talk  to  can't  understand  why 
they  hear  5  squelches  drop 
out. 

Now  for  an  explanation  of 
the  circuit.  The  whole  idea 
centers  around  any  old  op 
amp  you  have  lying  around 
(within  bounds  of  reason,  of 
course  ...  it  works  better  if 
the  op  amp  is  not  burned 
out).  I  have  had  the  best  luck 
with  either  the  741  or  the 
709  op  amp*  but  several 
others  should  work  also. 

As  shown  in  Fig,  1,  the 
circuit  is  simple  and  straight- 
forward. Let's  review  the 
basics  of  how  op  amps  work. 
Keeping  this  explanation  in 
mind,  the  workings  of  the 
circuit  in  Fig.  1  should  be 
obvious  to  the  most  casual 
observer.   An  op   amp   is  an 


The 


Minute  COR 


-  -  simplest  yet  ? 


Steve  Uhrig  WAZSWS 
3B93  Jumper  HUl  Lane 
Ellwott  City  MD  21043 


analog  device.  In  a  nutshell, 
the  gain  of  an  op  amp  (opera- 
tional amplifier)  is  very  high* 
Gains  of  100,000  to  500,000 
are  not  uncommon.  Of 
course,  the  output  can  never 
go  higher  than  the  supply  rail, 
so  you  can  see  that  an  input 
to  an  op  amp  of  1  millivolt 
will  give  an  output  of  10  volts 
even  if  you  run  the  gain  at 
only  10,000.  Notice  the 
inputs  in  Fig.  1  marked  +  and 
-,  These  are  called  the  non* 
inverting  and  inverting  inputs 
respectively.  The  op  amp 
amplifies  the  difference 
between  these  two  inputs.  In 
this  application  for  the  COR 
we  are  using  the  op  amp  as  a 
comparator.  I  will  stop  here 
for  a  moment  and  give  a 
quick  review  of  the  workings 
of  a  squelch  circuit  in  an  FM 
receiver.  See  Fig.  2  for  a 
block   diagram  of  a  squelch 

circuit. 

The  output  of  the  discrim- 
inator will  have  noise  on  it 
when  there  is  no  incoming 
signal  present.  When  a  signal 
does  present  itself,  the  noise 
will  quiet.  A  squelch  circuit  Is 
designed  to  turn  off  the  audio 
stage  in  the  receiver  when  no 
signal  is  present  so  the  oper- 
ator does  not  have  to  listen  to 
the  noise.  With  no  signal 
coming  in,  we  said  there 
would  be  noise  at  the  output 
of  the  discriminator.  This 
noise  (ac)  is  rectified  and  the 
dc  is  amplified  by  the  noise 
amplifier.  The  dc  signal 
developed  is  used  to  conduct 
another  transistor  which  In 
turn  shunts  any  audio  present 
at  the  audio  stage  to  ground. 
When  a  carrier  comes  in,  the 
noise  will  quiet.  With  no 
noise  present  at  the  rectifier 
in  the  squelch,  no  voltage  is 
developed  and  the  audio 
amplifier  operates  normally. 
Now  here's  where  our  carrier 
operated  relay  does  its  thing. 
Hang  a  voltmeter  across  the 
emitter-collector  junction  of 
the  audio  amplifier  transistor. 
With  the  stage  off,  there  will 
be  a  difference  in  current 
flow  and  therefore  voltage 
across  this  junction. 

Notice  the  inverting  input 
of  the  op  amp  in  Fig,  1.  This 
input   is   huoked   directly  to 


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the  collector  of  the  audio 
amplifier  preamp  transistor. 
You  can  see  now  that  there 
will  be  a  higher  voltage  on 
this  input  when  the  transistor 
is  turned  off  than  when  it  is 
amplifying.  The  non-inverting 
input  of  the  op  amp  is  tied  to 
a  reference  voltage,  in  this 
case  B+.  The  reference 
voltage  will  remain  constant, 
but  the  voltage  on  the  other 
input  will  shift  when  a  carrier 
comes  in  on  the  receiver  and 
turns  on  the  audio  stage.  The 
op  amp  will  amplify  the 
difference  and  drive  the  out- 
put to  the  full  supply  rail 
voltage  with  as  little  as  1 
millivolt  between  the  inputs. 
The  output  voltage  can  be 
used  to  trip  either  a  low 
current  relay  or  it  can  turn  on 
a  transistor,  I  used  a  reed 
relay,  but  any  type  with  a 
coil  current  of  less  than  75 
mA  is  acceptable-  Check  the 
specs  on  your  particular  op 
amp  before  using  anything 
that  might  draw  this  much 
current.  Under  no  eircum- 
stances  draw  more  than  100 
mA  from  the  op  amp. 


The  1  k  pot  on  the  non- 
inverting  input  of  the  op  amp 
sets  the  reference  voltage. 
The  setting  here  will  depend 
on  where  and  how  you  hook 
the  op  amp  to  the  receiver 
audio  stage*  Set  it  so  the  COR 
trips  reliably  on  an  incoming 
signal.  Try  to  keep  this 
voltage  as  low  as  you  can  and 
still  keep  the  circuit  operating 
property.  The  47k  Ohm  re- 
sistor limits  maximum  cur- 
rent on  the  input.  There  are 
probably  about  six  places 
where  you  can  tie  the  in- 
verting input  of  the  op  amp 
to  the  receiver.  Anywhere 
you  have  a  voltage  change 
between  signal  and  no  signal 
will  work.  If  it  doesn't  work 
the  first  time,  swap  the  leads 
to  the  +  and  -  inputs.  It  may 
be  that  you  have  picked  a 
point  where  the  voltage 
swings  in  the  wrong  direction. 
Don't  leave  out  the  diode 
across  the  relay  coil.  When 
the  relay  opens  up,  there  is  a 
big  voltage  spike  that  could 
damage  the  op  amp  if  the 
diode  wasn't  there  to  shunt 
it 


AUDIO  AVPi_,FiEA 


DISCRIMINATOR 


AUQlO 


N THRESHOLD 
i«* !  ADJUST 

NOISE 

RECTIFJER       /^\ 


njt 


NOtSE 

AJIPLIF«E« 


AUDIO 
CUTOFF 


Fig.  2.  Block  diagram  of  squelch  circuit  for  FM  receiver* 


Another  interesting  use  for 
this  COR  besides  repeater 
applications  is  to  use  it  to 
inhibit  a  clock  on  a  scanner. 
Use  the  transistor  output  and 
when  a  carrier  comes  in  on 
the  receiver  you  can  kill  the 
clock  and  lock  the  scanner  on 
that  frequency.  When  the 
carrier  dropsl  the  clock  will 
start  up  again  and  resume 
scanning.  It  is  possible  to  put 
a  capacitor  in  the  circuit  to 
delay  the  transistor  shutting 
off  immediately  if  you  should 
want  the  scanner  to  wait  a 
few  seconds  so  you  don't 
miss  any  possible  reply  on  the 
channel   that  was  just  active. 

Well  ...  here  you  have  It 


Construction  is  simple.  I 
build  my  versions  on  the  little 
printed  circuit  boards  avail- 
able from  Radio  Shack. 
They're  a  convenient  way  to 
do  it  and  are  small  enough  to 
fit  in  anything  larger  than  a 
TR-22.  If  you  desire  to  use 
the  COR  on  a  vacuum  tube 
receiver,  build  a  voltage 
divider  on  both  inputs  to 
keep  the  operating  voltages 
around  15  or  20  V  dc. 
Voltage  from  the  push  to  talk 
line  should  be  of  acceptable 
quality  to  power  the  op  amp 
if  you  filter  it  a  little  bit. 

There  are  lots  of  uses  for 
CORs.  They're  a  lot  of  fun  to 
play  with.  ■ 


153 


Gerald  X  Hargett 
Fine  fie  ids  Farm 
Route  2,  Box  68- E 
McComb  MS  39648 


See  the 


and  Get  Paid ! 


-  -  merchant  marine  radio  officers:    ESI 

part  II 


For  illustration  we  will 
follow  a  radio  officer 
through  a  routine  departure, 
His  ship,  SS  Valiant,  is  a 
tanker  making  a  transit  from 
the  port  of  Houston,  Texas  to 
the  port  of  New  York,  New 
York.  This  trip  normally  re- 
quires a  little  over  five  days. 
Our  radio  officer,  " Sparks/1 
is  a  conservative,  thorough 
individual.  Often  this  radio 
officer's  meticulous  logkeep- 
ing  goes  beyond  the  absolute 
minimum  regulation  compli- 
ance. By  being  overzealous, 
Sparks"  hopes  to  avoid 
sloppiness"  on  essentials.  As 
is  the  custom,  our  radio  offi- 
cer is  on  board  the  vessel  one 
hour  before  posted  sailing 
time.  Since  the  SS  Valiant  is  a 
tanker  alongside  the  terminal, 
transmitter  testing  is  not  per- 
mitted. However,  the  other 
items  in  the  pre-departure 
routine  can  be  checked  and 
logged.  This  pre-departure 
testing  is  neatly  typed  in  the 


u 


tt 


log  and  signed  with  the 
testing  time.  The  log  re- 
sembles ihe  following: 


4*25-75 

14QQGMT  —  Pre-departure 
tests,  Houston  terminal 
Main  and  emergency  re* 
ceivers  work  property;  8 
battery  voltage  88  V  dc 
under  toad;  ship's  line  1 18 
V  ac;  emergency  battery 
specific  gravity  1278,  bat- 
teries on  continuous  trickle 
charge  of  proper  polarity; 
auto-alarm  checks  OK  — 
keys  after  4  spaced  dashes: 
alarm  keyer  functioning 
normal;  speaking  tube 
c  o  mm  u  nica  tio  ns  to  the 
bri  dge  o  p  erabte;  ra  dio 
room  emergency  fights 
burning  normally;  antennas 
visually  checked  and  appar- 
ently in  good  order,  Trans* 
miners  wit  I  be  tested  away 
from  dock  and  radiation 
no  red  (an  re  n  na  curren  r/. 
Radio  room  clock  checked 
against  WWV,  3  seconds 
fast /corrected.  Aft  publica- 
tions  and   required  spares 

on      board.      Tester     

(signed) 


Once  the  vessel  is  cleared 
of  the  dock,  main,  emergency 
and  lifeboat  transmitters  will 
be  tested.  The  main  trans- 
mitter will  generally  put 
twelve  or  so  rf  Amperes  into 
the  main  antenna;  the  emer- 
gency t    approximately    three 

to  four  rf  Amps. 

Since  it  is  several  hours  to 
the  sea  buoy  (departure  point 
for  the  sea  passage),  the  radio 
officer  is  free  of  watch  stand- 
ing duties.  Sea  watches  in  the 
radio  room  are  from  sea  buoy 
to  sea  buoy.  Some  companies 
require  watch  standing  on 
long  river  transits.  Whatever  is 
in  the  contract  will  be  imple- 
mented. "Sparks"  will  copy  a 
weather  broadcast  from 
Galveston  radio,  KLC*  at 
1730  GMT.  This  will  contain 
Gulf  of  Mexico  weather  data. 
Radio  officers  endeavor  to 
copy  weather  "ahead"  so  the 
captain  can  be  made  aware  of 
wind  and  sea  conditions.  This 
information     enables     the 


master  to  plan  the  most 
direct    and   safest   routes;  it 

also  allows  for  more  accurate 
estimated  time  of  arrival 
(ETA)  messages. 

At  1900  GMT  the  ship 
drops  the  pilot  and  takes 
departure.  The  radio  officer 
begins  watch  standing.  The 
log  is  signed  noting  that  a 
listening  watch  on  500  kHz  is 
in  progress.  Every  fifteen 
minutes  a  log  entry  is  made 
of  noted  exchanges  which 
occurred  during  that  period. 
Silent  periods  (15-18  and 
45-48  minutes  past  each  hour 
ate  designated  quiet  listening 
segments  for  any  distress 
signals)  are  logged  as  having 
been  observed  and  as  to 
whether  or  not  signals  were 
copied.  At  times  the  circuit 
will  be  quiet  with  no  ex- 
changes occurring  during  the 
fifteen  minute  segment  -  this 
fact  is  so  logged.  Under  a 
as  on  the  operating 
position  are  schedules  of 
traffic  lists,  weather  and 
hy  drographic  bulletins, 
station  frequencies  and  other 
pertinent  data.  These 
schedules  are  kept  when 
applicable.  From  experience 
"Sparks"  knows  that  the  bulk 
of  company  traffic  is  handled 
through  Port  Arthur  radio, 
station  WPA.  By  following 
WPA's  schedules  very  closely, 
messages  are  often  received 
minutes  after  they  are  filed. 

As  the  ship  gets  under 
way,  the  captain  will  have 
time  to  prepare  the  routine 
departure  messages  and  re- 
ports. These  are  then  given  to 
the  radio  officer  who  will 
process  them*  This  involves 
counting  words,  noting  filing 
time  and  date,  proper 
addresses,  etc.  The  radio 
officer  then  transmits  the 
messages  to  the  appropriate 
station (s).  Once  cleared,  the 
messages  are  typed  on  formal 
cablegram  blanks  and  filed 
for  end  of  month  processing. 
The  master  is  given  the 
original  copy.  One  copy  is 
filed  for  the  company  to 
receive,  and  another  copy  is 
sent  to  the  radio  agency  for 
abstracting  (computation  of 
charges). 


154 


Suppertime  comes  and 
goes.  After  a  brief  recreation 
chess  match  with  one  of  the 

off  duty  mates,  "Sparks"  is 
ready  for  the  evening  watch. 
Weather  is  again  copied  up- 
dating the  earlier  report. 
Traffic  lists  are  checked  for 
close  of  business  day  mes- 
sages which  often  are  filed. 
The  log  is  kept  current.  At  9 
pm  ship's  time  the  watch 
ends.  Our  radio  officer  sets 
the  auto-alarm.  This  fact  is 
noted  and  the  log  is  signed 
out. 

This  ebb  and  flow  of 
routine  matters  allows  the 
voyage  to  New  York  to  pass 
quickly.  The  radio  officer 
may  be  asked  to  check  the 
radar  or  loran  or  DF,  minor 
problems  may  develop  in  one 
of  the  receivers  or  trans- 
mitters, or  orders  may  be 
received  to  proceed  abruptly 
to  some  other  destination. 
Each  day  brings  its  own 
challenges.  After  eighty  days 
on  the  tanker,  the  radio 
officer  will  be  relieved  for 
forty-five  days  paid  vacation. 
This  time  will  be  used  to  rest 
up  from  the  sea  routine. 
Perhaps  "Sparks"  has  some 
budding  business  interests  -  a 
farm  or  rental  properties  to 
attend,  or  some  recreational 
development.  Some  radio 
officers  simply  enjoy 
spending  a  large  amount  of 
time  off  with  the  family. 
Whatever  the  preoccupation, 
the  time  passes  once  again 
and  "Sparks"  will  be  notified 
to  report  back  to  the  same  or 
some  other  vessel.  The  radio 
officer  will  bring  his  or  her 
growing  electronic  knowledge 
and  experience  to  bear  once 
again  on  any  situation  the 
next  eighty  days  on  ship- 
board will  bring. 

Traffic  Handling 

Traffic,  messages  sent  and 
received,  take  up  a  good 
portion  of  a  radio  officer's 
watch  time.  Commercial 
operators  have  always  prided 
themselves  in  their  ability  to 
handle  a  targe  volume  of 
traffic  with  dispatch,  The 
commercial  operator  is 
trained    to    copy    with    one 


Photo  courtesy  of  Gene  D.  LeoJer,  Editor,  Exxon  Ffeet  Newst  Exxon  Company,  U.S.A.,  Houston  TX< 


hundred  percent  accuracy 
exactly  what  he  hears.  Most 
operators  become  proficient 
enough  with  the  typewriter 
to  almost  sign  their  names. 
When  one  considers  the  high 
costs  of  operating  oceangoing 
vessels  today,  one  appreciates 
the  need  for  accuracy  in 
messages.  Costly  cargo  opera- 
tions, tugboat  standby  time, 
or  overtime  for  repair  people 
can  all  be  the  direct  result  of 
inaccuracies  in  cables.  That  is 
one  reason  every  commercial 
operator  carefully  checks  a 
received  message  for  word 
count  before  acknowledging 
(OSLing)  it 


The  ability  of  commercial 
operators  to  handle  traffic 
well  is  due  in  part  to  standard 
operating  techniques.  Crisp, 
snappy  Morse  exchanges  with 
no  superfluous  sending  are 
the  key  to  professional  radio 
operating.  For  those  not 
familiar  with  commercial 
procedures  a  contact  will  be 
briefly  outlined.  Ship  station 
KAVQ  wants  to  send  traffic 
to  coast  station  WPA,  Port 
Arthur  radio,  using  the  12 
MHz  band.  The  radio  officer 
tunes  his  receiver  to  WPA's 
marker  frequency  (12840) 
and  then  calls  on  KAVQ's 
calling     frequency     (duplex 


operation).  Station  WPA  is 
constantly  scanning  the 
calling  band.  Rigid  FCC  rules 
must  be  adhered  to  regarding 
length  and  spacing  of  calls. 
WPA  hears  KAVQ  calling  and 
communication  is  established. 
The  ship  station  will  change 
(QSS)  to  the  FCC  assigned 
working  frequency  after 
advising  WPA  which  this  is  so 
Port  Arthur  can  tune  its  re- 
ceiver to  KAVQ's  working 
wave.  Once  QSS  is  accom- 
plished and  communication 
established,  KAVQ  asks  WPA, 
MQRV?"  (Are  you  ready  to 
copy?)  WPA  sends  K  and 
KAVQ  responds  as  follows  (a 


l 


"dummy"  message  for  illus 

tralion): 


MfiGNfl  1  5S5TAH0(,iii*HI3GtfTfI 

lAflHEWVOflPC  HT 
FT*  IflTMOSTOHEaLflHt  HUM  SUNK EHS  f T 


Examining  this  message  we 
find  the  following: 

Preambie:  Consisting  of 
message  class  <MSG)f  number  (1), 
word  check  (8),  date  (16),  and 
time  (1423  GMT}  of  filing.  A  BT 
is  sent  signifying  to  the  receiving 
operator  to  throw  the  carriage  of 
the  typewriter  as  a  break  is 
needed. 

Address:  This  is  usually  a 
cable  -id  dress  such  as  "  Key  star" 
followed  by  ihe  name  of  the  cily 
in  which  addressee  is  located 
(New  York],  Again  a  BT  signifies 
a  break, 

Text;  The  actual  message  it- 
self. Followed  by  BT 

Signature:  Not  always  con- 
tarried  in  cabJes, 

In  counting  words,  each 
word  in  the  address,  text,  and 
signature  is  counted.  As  an 
operating  aid  ihe  signal  AR  is 
sent  at  the  end  either  of  the 
texi  after  BT  or  after  the 
signature  to  indicate  the  end 
of  this  particular  message.  If 
another  message  is  to  follow, 
the  operator  will  simply  send 
the  class  designation  after  the 
AR.  For  example,  after  AR 
the  radio  officer  will  send 
NRT     to     indicate     another 


message  of  the  NRT  type  will 
be  sent.  The  coast  station  will 
acknowledge  with  a  "Q5LM 
and  indicate  a  "K"  or  "QRV1' 
to  let  the  sending  operator 
know  the  next  message  can 
he  sent. 

When  the  coastal  station 
has  a  message  the  same  for- 
mat is  followed.  In  place  of 
the  ship's  name  in  the 
preamble  will  appear  the  city 
of  message  origination. 
Rather  than  a  cable  address, 
the  message  will  be  addressed 
to  the  vessel;  usually  the 
master's  title  will  precede  the 
vessel's  name.  Thus: 


M5C  NH  I  MEW  VOMK  CK  T  IB  ?JflffjMT  BT 

HANKERS  ACKNOWLEDGES  CAU,  QfftGE  SOONEST  »T 
Afl 


Traffic  handling  facility  is 
acquired  through  practice. 
Time  spent  listening  to  lop 
professional  commercial  oper- 
ators at  the  busier  marine 
stations  (WCC,  WSL,  JC5, 
etc)  is  a  good  investment. 
With  experience  the  begin- 
ning radio  officer  will  appre- 
ciate the  skifl  involved  in 
apparently  simple,  efficient 
exchanges  of  Morse.  The 
master  operator  sends  not 
one  unnecessary  dot  or  dash. 

Mechanics  of  counting 
words  (doubles,  triples,  etc.), 


assigning  prefixes,  and 
routing  messages  is  acquired 
through  usage  and  imitation 
of  accepted  commercial 
practices.  ITT  Mackay  Marine 
has  a  comprehensive  "Radio 
Officer  Manual"  which  details 
message  processing  as  well  as 
a  wealth  of  other  informa- 
tion. All  ITT  Mackay  con- 
tract ships  have  a  copy  of  this 
text.  RCA  has  a  similar  publi- 
cation on  its  contract  vessels. 
With  practice  and  attentive 
listening,  a  new  radio  officer 
will  soon  become  proficient 
in  traffic  handling. 

Standard  Shipboard  Publica- 
tions for  the  Radio  Officer 

All  licensed  shipboard  in- 
stallations are  required  to 
have  on  file  the  following 
publications  in  order  to  meet 
with  full  FCC  compliance. 
Required  documents  are 
included  in  the  list. 

tt  Valid  station  license. 

2.  Valid  operator  license. 

3.  Required    station   logs, 

4.  Alphabetical  list  of  call- 
signs  of  stations  used  by  the 
maritime  mobile  service  — 
current  edition. 

5.  List  of  ship  stations  — 
current  edition, 

6.  List  of  coast  stations  — 
current  edition. 

7.  List  of  radiodeter  mi  na- 


tion    and     special     service 
stations. 

8.  Manual  for  use  by  the 

maritime    mobile    service    — 
ITU  Geneva* 

9.  Part  83  of  FCC  Rules 
and  Regulations. 

With  the  above  reference 
publications,  the  ship  may  go 
any  place  in  the  world  and 
the  radio  officer  will  be  able 
to  locate  appropriate  coastal 
stations,  their  schedules, 
tariffs,  routings,  time  ticks, 
and  other  needed  data.  A  few 
explanatory  paragraphs  will 
be  given  regarding  the  publi- 
cations and  documents. 

1  and  2.  A  valid  station 
license  is  extremely  impor- 
tant. The  radio  officer  should 
inform  the  master  if  the 
license  is  nearing  expiration. 
Heavy  penalties  are  incurred 
for  invalid  licenses.  It  is 
assumed  the  radio  officer's 
licenses  are  current  and 
posted. 

3.  Station  togs  as  well  as 
other  required  stationery  are 
usually  supplied  by  the  con- 
tracting agency.  Message 
blanks,  requisition  forms,  and 
work  orders  are  all  supplied 
by  the  husbanding  radio  con* 
tract  company.  Other  normal 
stationery  items  (pens, 
pencils,  notepads,  etc.)  are 
supplied  by  the  particular 
steamship  company.  The 
radio  officer  is  responsible  for 
keeping  the  inventory  at 
reasonable  levels:  usually  six 
months  of  supplies  are  coiv 
sidered  adequate. 

4.  A  quick  reference 
manual  for  identifying  ships 
or  coastal  stations  from  their 
assigned  call  letters.  New 
editions  are  constantly  being 
published  to  keep  the  radio 
officer  abreast  of  changes. 

5.  This  is  a  more  elaborate 
manual  (over  500  pages) 
listing  ships  alphabetically  by 
name.  Pertinent  data  is  given 
for  each  ship:  type  of  equips 
ment  (telephone,  telegraph, 
etc.),  hours  of  service,  ship 
classification  and  other  useful 
information  concerning  the 
communications  ability  of 
the  vessel.  The  present 
edition  contains  information 
on  over  52,000  stations. 

6.  Perhaps     the     most 


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157 


important  and  useful  publica- 
tion. It  gives  the  radio  officer 
a  tool  which  can  direct  him 
or  her  to  unfamiliar  ports  of 
call.  The  list  contains 
pertinent  information  on 
coastal  maritime  stations 
around  the  world.  It  is  repub- 
lished every  two  years; 
supplements  are  issued  every 
six  months.  This  manual  con- 
tains three  parts:  a.  Alpha- 
betical index  of  coast 
stations;  b.  Full  particulars  of 
each  station  -  frequencies! 
operating  times,  traffic 
listings,  particular  communi- 
cation procedures;  c.  An 
annex  which  gives  inland  tele- 
graph rates,  tariffs,  and  other 
monetary  information.  Once 
a  radio  knows  the  vessel's 
itinerary,  this  publication  can 
be  consulted  and  schedules 
planned. 

7.  The  manual  of  radio- 
determination  and  special 
services  can  be  considered  the 
next  in  relative  importance* 
Part  A  of  it  gives  an  alpha- 
betical index  of  all  stations 
listed.  Part  B  gives  the  partic- 
ulars of  these  stations.  The 
most  useful  of  these  are  the 
areas  of  radiodetermi  nation 
(direction  bearing  stations), 
time  signal  information  for 
accurately  setting  of  chro- 
nometers, and  stations 
dispensing  medical  advice. 
The  publication  is  complete 
and  comprehensive.  The 
present  edition  contains  750 
pages. 

8  and  9.  These  publica- 
tions contain  regulatory 
matter.  The  first  has  chapters 
on  internationally  agreed 
regulations  and  procedures; 
the  second  contains  the 
Federal  Communications 
Commission's  regulations  for 
the  Maritime  Mobile  Service, 
These  are  excellent  operating 
aids. 

Besides  the  above  publica- 
tions, each  radio  room  will 
have  on  file  the  various  oper- 
ating and  technical  manuals 
covering  the  electronic  equip- 
ment installed.  These  repre- 
sent invaluable  service  tools 
and  maintenance  aids.  They 
give  prints,  upkeep  informa- 
tion, parts  nomenclature, 
troubleshooting     procedures, 


and  correct  operating  teclv 
niques.  Almost  any  repair 
situation  can  be  solved 
through  judiciously  studying 
the  manual.  If  an  exact 
remedy  cannot  be  found,  the 
general  area  of  fault  can 
usually  be  determined  —  in- 
formation helpful  in  ordering 
shore  repairs. 

Basic  Electronic  Maintenance 

Newly  documented  radio 
officers  channel  their  efforts 
at  first  to  teaming  the  "radio 
operating*'  aspect  of  the 
profession.  However,  it  will 
soon  become  evident  that 
more  is  expected  of  a  ship's 
radio  officer-  As  indicated  in 
other  sections,  the  actual 
operation  of  the  radio  station 
becomes  routine  with  ex- 
perience. A  radio  officer's 
other  responsibility  is  the 
proper  maintenance  of  the 
station  as  well  as  other  elec- 
tronic equipment  within  his 
or  her  ken.  In  addition  to  the 
receivers,  transmitters,  power 
supplies  and  chargers  located 
In  the  radio  room,  a  com- 
petent sparks  also  will  keep  in 
proper  operating  order  the 
radars,  loran,  direction  finder, 
recreation  shortwave  re* 
ceivers,  and  televisions  on 
board  the  vessel,  A  person 
who  can  handle  this  varied 
array  of  equipment,  keep 
shoreside  repair  bills  to  a 
minimum,  and  obtain  maxi- 
mum performance  from  the 
communication  and  naviga- 
tion gear  is  much  sought  after 
by  companies  and  captains 
alike.  This  section  will  delve 
into  some  very  basic  concepts 
of  shipboard  electronic  main* 
tenance.  The  subject  is  an 
exhaustive  topic  and  spans 
the  life  and  career  of  each 
radio  officer. 

All  electronic  equipment 
contains  normally  a  combina- 
tion of  electronic  circuitry 
and  mechanical  movements 
(dials,  drives,  relays,  multi- 
contact  switches,  etc.).  While 
this  apparatus  is  designed  to 
operate  in  a  vigorous  salt  air 
environment,  the  pounding  of 
the  ship,  exposure  to  heavy 
humidity,  and  operation  by 
many  individuals  all  take 
their   toll   on  equipment  per- 


formance. One  simple,  basic 
preventative  maintenance 
program  is  to  keep  the  equip- 
ment clean  of  salt  and  cor- 
rosion. Wiping  surfaces, 
cleaning  and  lubricating 
contacts,  burnishing  pitted 
relays,  lightly  greasing  cams, 
gears,  chain  drives,  reseating 
tubes  and  crystals  to  remove 
any  corrosion  from  forming 
on  pins  —  all  these  elemen- 
tary procedures  will  con- 
tribute to  optimum  operation 
of  electronic  gear. 

Electronic  apparatus 
employing  high  powered  elec- 
tron tubes  can  be  disabled 
through  a  simple  filament 
break  in  one  of  the  high 
temperature  tubes.  This  is  a 
basic  defect  to  investigate 
when  this  type  of  equipment 
fails.  Power  transistors  are 
subject  to  the  same  type  of 
thermal  punishment  and 
often  open  or  short  under 
such  pressures. 

Electronic  troubleshooting 
requires  organized  logical 
thinking.  No  matter  how 
complex  the  unit  to  be 
serviced,  it  contains  the 
workings  of  the  three  basic 
electronic  circuits:  rectifiers, 
amplifiers  and  oscillators.  If  a 
person  has  a  sound  grasp  of 
the  operation  of  these 
circuits,  the  defective  element 
(resistor,  coil,  capacitor)  can 
often  be  pinpointed  through 
simple  voltage  and  resistance 
measurements.  The  prints 
contained  in  the  manuals 
offer  clues  as  to  what  proper 
readings  should  be  found. 
Any  wide  deviation  from 
suggested  call-outs  in  an  elec- 
tronic print  should  alert  the 
radio  officer  to  seek  reasons 
for  the  deviation;  often  the 
"reasons"  will  be  the  faulty 
component  located. 

As  with  radio  operating, 
one  becomes  proficient  in 
basic  maintenance  and 
troubleshooting  of  gear  with 
experience.  Certain  faults  will 
occur  over  and  over.  Even- 
tually symptoms  will  be 
immediately  recognized  and 
the  fault  will  be  rapidly  re- 
paired. Many  radio  officers 
work  at  one  time  or  another 
at  repair  depots  ashore.  These 
ire    either    electronic    main- 


tenance companies,  television 

repair  facilities  or  two-way 
radio  repair  terminals.  This 
shoreside  experience  is 
valuable.  Techniques  are 
developed  which  speed  ser- 
vicing. Much  can  be  learned 
from  senior  technicians  with 
many  years  of  experience. 
These  people  are  usually 
more  than  willing  to  share 
their  experiences  with 
beginners, 

It  is  well  to  note  at  this 
point  that  radio  officers 
receive  base  wages  for  the 
eight  hours  (normally)  watch 
standing.  All  repair/main- 
tenance work  is  additional 
compensation  earned  outside 
watch  hours,  Shipping  com- 
panies have  found  even  with 
the  overtime  paid  they  still 
are  ahead  economically. 
Large  service  companies  of 
necessity  charge  high  rates. 
They  may  have  to  travel  long 
distances,  wait  hours  for 
delayed  arrivals,  and  in 
general  contend  with  costly 
overhead  expenses. 

With  advances  in  modern 
day  technology,  satellite  com- 
munication capabilities,  and 
automated  telex  (unattended) 
terminals  installed  aboard 
ships,  it  is  very  possible  that 
international  and  national 
regulations  will  be  amended 
some  day  possibly  eliminating 
the  traditional  role  of  radio 
officer  as  presently  known. 
However,  it  is  the  consensus 
of  all  those  knowledgeable  in 
shipboard  manning  policies 
that  a  place  will  always  be 
available  on  a  vessel's  articles 
for  some  type  of  "electronic 
officer/'  a  person  (male  or 
female)  who  can  cope  with 
sophisticated  equipment  and 
effect  repairs  necessary  to 
keeping  communications 
"alive1*  between  the  vessel 
and  shore.  No  one  will 
venture  how  far  into  the 
future  this  situation  will 
materialize.  However,  the 
technology  is  available  today. 
Regulatory  agencies,  how- 
ever, require  lengthy  periods 
to  legislate  major  changes. 
The  person  who  keeps  aware 
of  advances  in  communica- 
tion electronics,  broadens  his 
or    her    electronic    expertise 


158 


through  study  and  applica- 
tion, and  brings  a  common 
sense  practical  trouble- 
shooting approach  to  repair 
situations  has  taken  positive 
steps  to  enhance  his  or  her 
worth  to  the  company  and 
keep  the  job  secure. 

Goals 

It  is  hoped  that  the  reader 
has  found  helpful  informa- 
tion in  these  pages,  I  have 
attempted  to  bring  together 
material  aimed  at  positive 
means  of  joining  the  ranks  of 
radio  officers,  As  in  many 
narrow  specialties,  it  is  diffi- 
cult to  "break  in"  the  pro- 
fession of  radio  officer.  The 
rewards  as  hinted  are  ample 
for  those  who  pursue  the 
necessary  courses  of  action  to 
qualify.  The  opportunities  are 
open  to  both  men  and 
women.  Foreign  flag  vessels 
have  employed  female  radio 
officers  for  years.  Many  of 
these  women,  in  addition  to 
sending  beautiful  commercial 
CW    Morse,    are    competent 

electronic  technicians. 

As  in  any  profession  one 
encounters  the  excellent,  the 
mediocre,  and  the  incom- 
petent, Anyone  seriously 
endeavoring  to  embark  on  a 
seagoing  career  as  a  radio 
officer  is  wholeheartedly 
encouraged  to  strive  for  ex- 
cellence in  performance.  Con- 
scious awareness  of  sending 
good  CW,  meticulous  log- 
keeping,  faithful  performance 
of  required  tests,  error- less 
copies  of  messages,  weather 
reports,  hy  d  ro graphic 
bulletins  —  all  these  mark  the 
truly  professional  radio 
officer.  After  becoming 
settled  in  commercial  radio 
operating,  further  study  to 
acquire  the  radar  endorse- 
ment on  one's  license  will 
enable  the  holder  to  perform 
more  complex  maintenance 
on  these  units.  Passing  the 
higher  code  test  after  a  full 
year's  service  is  acquired  will 
grant  the  radio  officer  the 
first  class  radiotelegraph 
license,  the  apex  in  certifica- 
tion. Proficiency  in  repair  and 
maintenance  of  electronic 
equipment  will  bring  addi- 
tional financial  remuneration 


as  well  as  a  gratifying  sense  of 
technical  achievement. 

A  sincere  ll73"  and  best  of 
luck.  May  your  efforts 
toward  becoming  a  Merchant 
Marine     radio     officer     be 

crowned  with  success,  ■ 

APPENDIX  A 

Maritime  Station  Information 

Traffic  Lists 

Weather  Schedules 

Selected  Operating  Frequencies 

All  Time  GMT 


IRAFflCUSTS  OsSdHom 

K,LC  (GalvciionT*)  30 
WHM  < Baltimore  MD)  30 

WSHAm*|MY)50 

KPH  |Sxri  Frjn  CA]  on  hour 

KFS{San  Fran  CA)  3tt 

TRAFFIC  USTSj  £m  Hour* 

Wl.O  IMubilr  XI)  hour 

W04  [imam  *"l  r OS 
WPA|ft»nArtlu*TK)IS 
*M     s;,drftLA)J5 
WCC  lOutham  MAt  50 
KMK  (Miwdm  30 
KOk  (Li»Ar«rie«i5i> 

I J HER  SCHEDULE! 
GtilE  a'  Mr.ME.tJ 

K LC  0 5JdZ-\  f 30Z,  I  7 302J  2330Z 
fOQZ 

KFHO5O0 
KFS0*.?u 
KHk  ftSIO 

WWV/WWVH  5  mbl  10  WHl/1  S  Wit!? 5  MH? 

<1HU  (Otuwj,  CwutUj  nVi  LHz  7332  (lHi  146TO  kilt 


Vircird  **r«rtr  Snxton  frtqurm  irr  in  fcHantf u 


A&ijQf  SMtiom 


WPA 

416 

6435 

15 

12S4TJ 

WCC 

436 

6376 

856S 

13033 

KM 

4B4 

636* 

»666 

1303S 

WLO 

4U 

6446 

1722 

12704 

KPH 

426 

6467 

12B0B 

KF5 

436 

6365 

12544 

KHK 

4B4 

6407 

13029 

WHi 

47fl 

649S 

13*26 

•1*r  tti  t  €  r  rv/wu  *f  t  j 

Q&tftovr 

GKU  {London  I  nn  Hour 
SAG  (Sweden)  on  bffUl 
1-4  II  IHullinJ]  SPllsi 
0ST  f Belgium)  lQjuii 
DAN  (G*rrtLi^v)  30  past 

f  HI  AT  Jfow 

SVA  (AllwnJ  cm  hwr 
tCW  f**or*a>  J  an  how 
CIST  ffetpcnj  10  pan 
FFL  |Pw k|  30 past 


found  ift  frequent  riiL 

fetfrv  *«i/  ^  v  &M  Stefitom 

NBA  [Balboa,  Panama  C*ruj  font]  odd  huui 
/OS  (Chosl,  Japan)  Wi  pu\  cM  h&it 
HLf  (fuMin  Korea]  30  p^i  odd  Nwi< 

|N<   ljjuui»J  *nfn  *v  ■>' 
KUP  l(X  iru*j  i'  even  hi^ul 
DZG  J  Manila,  HI)  1*0  piit  f  tm 

HydinfiMptUcal  nr^millpft  li 

Hffl  frv  tution  MAM,  «*t  i 

VA.  fkoadcj  m  Throughout  dv 

tfUb    The  HOO  GMT  vchtdu* 

conutn-t  tnlorrmJion  fgr 

Nljjinrtx  Frequence*:  (in  kHrl 

««  5670 1»0  1 21 35  16IS0  20215  25530 

Station uw  Elieir  iriedmni  wa^t  thrLHj^h  t«tivi 
mtsfrih it  1 7  h.milb  iiJiJirlB  lii^hrr  Ircqu£f1£i£k 

when  pfop*n*Hnri  El  upcii 


APPENDIX  B 
Employment  Sources 

There  are  two  national 
maritime  radio  officer  unions. 
Each  of  these  unions  has 
branch  offices  in  all  major 
port  cities  of  the  United 
States  as  well  as  keeping 
headquarters  located  in  New 
York  City, 

The  first  of  these  two 
unions  is  the  American  Radio 
Association,  an  AFL-CIO 
affliate.  This  union  has  num- 
erous companies  under  con- 
tract: Lykes  Brothers  Steam* 


ship  Company,  Keystone 
Tanker  Company,  and  Ameri- 
can Export  Lines>  to  mention 
only  a  few.  Additional  infor- 
mation can  be  acquired  from 
either  the  headquarters  in 
New  York  or  any  of  the 
many  branch  offices  located 
around  the  country.  A  person 
shipping  via  a  union  hall 
usually  registers  at  the  office 
nearest  his  or  her  home  as 
transportation  reimbursement 
will  be  calculated  to  and  from 
this  point. 

Of  interest  to  radio  officer 
aspirants  is  the  Free  Press 
which  the  American  Radio 
Association  (ARA)  sponsors 
each  Sunday  at  1818  GMT, 
ITT  Mackay  station  WSl, 
Amagansette,  N,Y_,  transmits 
this  weekly  Press  on  fre- 
quencies {in  kilohertz)  6414, 
8514,  13078,  17021  and 
22485.  Items  in  this  Press 
concern  maritime  happenings 
of  the  past  week.  Special 
interest  is  shown  in  this  press 
when  new  contracts  are 
pending;  complete  details  are 
generally  sent* 

The  second  national  radio 
officer  union  is  named, 
appropriately  enough,  Radio 
Officer's  Union.  This  union 
also  has  branch  offices  in 
major  port  cities.  Companies 
which  utilize  men  from  the 


159 


ROU,  such  as  Mobil  Oil, 
Delta  Line,  and  many  others, 
depend  upon  the  union  to 
recruit  enough    members  to 

fill  any  vacancies  which 
occur. 

Governmem  agencies 
responsible  for  crewing  of 
specialized  vessels  represent 
an  excellent  source  of 
employment.  United  States 
Coast  and  Geodetic  Survey 
vessels  hire  qualified  civilians. 
These  ships  make  fine  berths 
for  a  person  to  enter  com- 
mercial radio  operating.  One 
may  even  opt  to  remain  as  a 
civil  service  employee  as  a 
career.  Generally  the  pay 
scale  on  such  vessels  is  lower 
than  on  other  commercial 
ships*  Thus  a  large  turnover  in 
manpower  is  ordinarily  ex- 
perienced. Military  Sealife 
Agency  (MSA),  with  offices 
in  New  York  and  San  Fran- 
cisco, concentrates  its  efforts 
using  civilian  crews  to  operate 
vessels  which  carry  exclu- 
sively military  cargo  items. 
The  Corps  of  Army  Engineers 
occasionally  requires  radio 
officer  personnel  on  its  large 
offshore  dredges  and  supply 
boats. 

Private  research  and  ocean* 
ographic  companies  generally 
hire  radio  officers  for  up- 
coming projects.  Herein  lies 
potential  employment  leading 
to  the  six  months1  endorse- 
ment,  as  many  of  the  research 
vessels  are  voluntarily 
equipped.  Texas  A  &  M 
University  operates  one  such 
vessel.  The  Woods  Hole,  Mass. 
project  has  its  project  ship. 
Inquiry  can  be  made  of  oil 
consulting  firms  which 
operate  survey  type  boats 
requiring  the  services  of  radio 
officers. 

Besides  the  national 
unions  for  radio  officer  regis- 
tration, many  smaller  steam- 
ship and  tanker  companies 
hire  individuals  without 
union  affiliation.  Most  of 
these  "independent"  com- 
panies do  have  "indepen- 
dent" or  company-organized 
unions  with  membership 
optional.  Such  companies  are 
Hess  Oil,  Sabine  Tankers, 
Exxon  U.S.A,  Tankers,  Sun 
Oil,     and     many     others. 


Inquiries  of  one  of  these  com- 
panies will  generally  glean 
'leads"  to  other  companies 
who  hire  independent  of 
union  affiliation.  Time  spent 
researching  the  yellow  pages 
of  the  phone  directory  of  any 
targe  port  city  will  lead  to 
positive  and  plentiful 
potential  employment 
sources, 

APPENDIX  C 

Types  of  Equipment 

Any  licensed  United  States 
Maritime  Mobile  Radio 
Station  is  required  to  have 
certain  minimum  equipment 
to  satisfy  compliance  with 
FCC  regulations.  Compul- 
sority  equipped  vessels  gen- 
erally will  have  the  following 
electronic  items  in  the  radio 
room: 

Reserve  Receiver:  This  can 
be  operated  from  battery 
supply  voltages  in  an  emer- 
gency. Frequencies  covered 
by  this  receiver  must  be  in 
the  15  kHz  through  the  650 
kHz  spectrum.  Most  older 
installations  use  superrengen- 
erative  receiver  circuitry. 
More  recent  installations  use 
low  power  consuming  transis- 
torized heterodyne  principles. 

Main  Receiver:  This  is  gen- 
erally an  extremely  well  built 
double  or  triple  conversion 
superheterodyne  circuitry 
receiver  which  operates  off 
the  ship's  mains.  Modern 
RCA  and  ITT  Mackay  re* 
ceivers  cover  80  kHz  through 
30  MHz  in  numerous  bands. 
For  convenience,  each  band 
usually  tunes  a  500  kHz  seg- 
ment of  the  band  desired  at  a 
time.  The  RCA  8516  model  is 
one  example  of  a  modern 
shipboard  general  coverage 
receiver.  All  modes  (AM,  CW, 
SSB)  of  reception  are 
included  as  well  as  a  variable 
bandwidth  to  help  copy 
signals  on  crowded  bands. 
The  ITT  Mackay  3010C  has 
become  a  standard  of  ex- 
cellence for  shipboard  re- 
ceivers. It  is  rugged,  stable, 
versatile  and  costly.  Made  to 
rigid  commercial  specifica- 
tions, this  receiver  gives  years 
of  service  with  minimum 
maintenance.  Terminology 
varies  regarding  the  "reserve" 


"main" 


receiver    con* 


and 
cepts. 

Main  Transmitter:  These 
installations  cover  400 
through  535  kHz  and  range  in 
output  power  from  200  Watts 
to  a  thousand.  The  more 
common  main  transmitters 
put  250  to  500  Watts  into  the 
antenna.  Both  A1  and  A2 
emission  modes  are  contained 
in  the  units.  Output  configur- 
ations of  these  transmitters 
enable  a  wide  variety  of 
antenna  types  to  be  used. 
Most  popular  is  the  longwire 
and  vertical  (top  hat)  loaded 
antennas. 

High  Frequency  Trans* 
mitter:  These  installations  are 
the  uniu  which  usually  get 
the  "communicating"  done 
over  long  distances.  It  is  quite 
normal  to  consistently 
"work"  home  stations  half- 
way around  the  world.  These 
HF  transmitters  generally 
cover  2  MH  through  24  MHz. 
Crystal  controlled  oscillators 
eliminate  off  frequency 
excursions.  Generally  a  ship 
will  have  two  calling  fre- 
quencies and  two  working 
frequencies  in  each  of  the 
harmonically  related  marine 
bands  of  2,  4,  6,  8,  12,  16, 
and  22  MHz.  Thus  a  poten- 
tially large  number  of  chan- 
nels are  available  for  needed 
communications.  Emission  of 
the  HF  transmitters  is  Al; 
however,  some  units  combine 
AM  telephone  operation  per- 
mitting A3  operation  in  allo- 
cated hands.  The  FCC  has 
legislated  that  no  amplitude 
modulation  be  permitted 
after  1977.  Ships  will  then  be 
required  to  use  the 
suppressed  carrier  single  side- 
band  transmission  mode. 
Many  ships  today  are  SSB 
equipped  for  its  excellent 
communication  ability. 

Reserve  Transmitter:  Like 
the  reserve  receiver,  this  must 
be  capable  of  operating  off 
emergency  battery  voltage. 
These  units  cover  350-515 
kHz  using  A2  emission  with 
output  power  in  the  50  Watt 
range.  Versatile  antenna  net- 
works allow  matching  of  even 
random  wire  lengths  should 
critical  situations  require  this. 

Auto-Alarm:   The  purpose 


of  this  device  is  to  stand  a 
watch  on  the  distress  fre- 
quency when  the  radio 
officer  is  unable  to  either 
because  he  is  off  cuty  or 
because  of  other  extenuating 
c  i  r  c  u  mstances.  The  inter- 
national alarm  signal  consists 
of  a  series  of  dashes  four 
seconds  in  lengthy  separated 
by  spaces  having  a  duration 
of  one  second.  Auto-aiarms 
designed  to  meet  FCC  specifi- 
cations arc  arranged  to 
actuate  an  audible  alert  (bell) 
when  four  correct  dashes  and 
spaces  have  been  received. 
Modern  alarms  utilize  tran- 
sistor circuitry  achieving  high 
reliability.  Older  alarms, 
through  a  system  of  stepping 
relays,  require  more  main- 
tenance to  keep  the  mechani- 
cal system  operative.  The 
auto-alarm  receiver  covers 
492  to  508  kHz.  Nominal 
standard  signal  is  of  50  micro- 
volts. 

Auto- Alarm  Keyer:  This 
unit  is  operated  in  conjunc- 
tion with  the  main  trans- 
mitter and  will  send  out, 
mechanically,  the  appropriate 
alarm  actuating  signals. 
Standard  procedure  is  to  send 
the  keyer  signal  for  a  minute 
followed  by  the  SOS  message, 

Battery  Charger(s):  The 
radio  officer  is  responsible  for 
keeping  the  emergency 
batteries  in  a  good  state  of 
charge  (specific  gravity  of 
1278  or  so).  Battery  charging 
devices  are  part  of  most  con- 
soled equipment  which  can 
be  manually  or  automatically 
operated. 

That  is  the  very  basic  radio 
equipment  found  on  com- 
pulsorily  fitted  vessels.  More 
elaborate  installations  will 
include  VHF/SSB/AM  radio- 
telephones, facsimile  receivers 
and  machines,  radioteletype 
equipment,  and  perhaps 
satellite  communications 
facilities. 

Bridges  of  vessels  are  fitted 
with  sundry  electronic 
devices.  Loran,  omega  re- 
ceivers, Decca  navigator  gear, 
ten  and  three  centimeter 
radars,  collision  avoidance 
computer  systems,  auto- 
piloting  systems,  and  remote 
radiotelephone     installations 


160 


are  some  of  the  more  com- 
plex items  found  on  modern 
day  vessels, 

APPENDIX  D 

Antennas 

A  moot  question  often 
develops  among  radio  engi- 
neers: What  is  more  impor- 
tant, a  higher  powered  trans- 
milling  system  or  a  re- 
designing of  the  antenna 
system?  This  answer  wilt  not 
completely  satisfy  both 
parties  but  is  sufficient  for 
discussion  purposes  here:  The 


better  the  radiating  facilities 
connected  to  a  transmitter, 
the  more  economical  and 
efficient  use  is  made  of  the 
power  required  to  produce 
increased  output-  Thus,  ship- 
board antennas  are  very 
important  devices  which 
require  special  consideration. 
Earlier  shipboard  radio 
history  details  that  simple 
longwire  antennas  worked 
efficiently  for  the  medium 
frequencies  being  generated. 
Even  today  the  best  radiator 
for  the  400-500  kHz  band  is  a 


good  longwire  stretched  as  far 
as  possible  between  two 
points  aboard  the  vessel. 
Ships  with  such  long  wires 
work  coastal  stations  at  far 
greater  distances  then  sister 
ships  equipped  with  verticals. 
However,  once  high  fre- 
quency transmission  became 
commonplace,  the  vertical 
antenna  proved  to  be  an  ex- 
cellent device  for  shipboard 
installation.  Rugged  and  effi- 
cient, a  vertical  cut  for  the  8 
MHz  band  and  properly 
loaded  for  others  can  effect 


around  the  world  communi- 
cations when  linked  to  a 
transmitter    in    the    200*500 

Watt  output  class.  In  special 
class  vessels  where  long  wires 
cannot  be  located,  the 
verticals  are  coil  loaded  to 
resonate  on  the  lower  fre- 
quencies. This  is  inefficient 
and  the  range  of  communica- 
tion diminishes.  Most  ships 
will  have  a  combination  of 
longwire  (s)  and  vertical 
antennas  to  take  advantage  of 
the  inherent  characteristics  of 
each. 


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price  and  sky-high  quality  make  it  your  best  buy! 
We've  proved  it  to  thousands. Let  us  prove  it  toyou! 

*  100m Hz  Readout     •  Ham,  CB<  &  Commercial  Bands 

•  1H2  Optional  •  Master  Chg./B.  Americard  OK 
'Crystal Time-Base  •  Add $2  Shipping 

All  counters  can  be  factory  wired  and  tested. 


Hufco 


Wnte  or  call  today* 
P.O.  Box  357,  Dept55, 
Provo,  UT  B4601  (801 )  375-8566 


161 


F.  Raymond  Dewey 
7  Caroline  Dr. 
Bennington   VT  Q52QI 


Watch  DX 

with  a  Spectrum  Analyzer 


-  -  seeing  is  believing 


If  you've  ever  seen  or  used 
a  spectrum  analyzer,  you 
know  how  valuable  they  are. 
After  calling  CQ  you  can  see 
the  signals  replying  without 
touching  the  receiver.  When 
chasing  DX  you  can  see  the 
weak  signal  before  hearing  ii 
and  therefore  tune  more  aire* 
fully.  An  analyzer  is  useful 
for  finding  clear  spots  in  a 
crowded  band  or  weak  signals 
in  a  quiet  band. 

Connecting  the  analyzer  to 
your  receiver  is  no  problem. 
The  analyzer  input  signal  is 
obtained  from  the  plate  of 
the  first  mixer  stage  of  the 
receiver.  The  frequency 
response  at  this  point  is  quite 
broad     and      enables     the 


054-30MHZ 


analyzer  to  view  as  much  as 
100  kHz  of  the  band. 

Unfortunately,  some  ama- 
teur and  general  coverage 
receivers  change  mixer  output 
frequencies  for  different 
bands  (as  shown  in  Fig,  1  for 
the  Hammarlund  HQ-180). 

With  this  type  of  receiver, 
either  2  spectrum  analyzers 
must  be  used,  or  one  analyzer 
to  cover  only  a  portion  of  the 
receiver  tuning  range,  or  one 
analyzer  with  an  external 
converter.  With  cash  output 
already  exceeding  income, 
the  XYL  was  not  exactly 
happy  about  buying  another 
analyzer;  Having  used  the 
analyzer  on  the  high  bands,  I 
was  lost  without  it  on  the  low 


455  KHz 
BANDS  I-4 


JGATE 


3  035  MHi 

BANDS 5aS 


455KHI 


bands.  I  therefore  decided  to 
build  an  external  converter  to 
convert  the  low  band  i-f  up  to 
the  high  band  i-f  required  by 
the  analyzer  {as  shown  in  Fig. 

2). 

The  oscillator  is  not 
critical,  but  should  be  crystal 
controlled  for  stability.  How- 
ever, I  was  reluctant  to  spend 
any  money  at  all,  and  the 
receiver  just  happens  lo  have 
a  crystal  oscillator  which  isn't 
doing  anything  when  the 
receiver  is  tuned  to  the  low 
bands.  With  the  addition  of  a 
Yi  Watt  resistor,  I  now  have 
my  oscillator,  and  if  the 
mixer  is  passive,  no  external 
power  supply  is  required. 
Granted,  I  now  have  a 
(tbirdie,i  at  2.58  MHz,  but  so 
what.  It's  not  in  an  amateur 


band  or  a  broadcast  band  and 
there  isn't  anything  else, 

The  completed  circuit  is 
shown  in  Fig.  3.  It's  simple,  it 
works,  and  best  of  all,  it's 
cheap.  Resale  value  is  not 
noticeably  affected  so  long  as 
the  extra  22  k£2  resistor  is 
removed  prior  to  sale. 

Construction  was  not  criti- 
cal, except  keeping  the  input 
away  from  the  output.  The 
diodes  can  be  almost  any 
decent  switching  type,  but 
should  be  germanium  (hot 
carrier  diodes  might  be  an 
improvement).  The  input 
transformer  is  normally  used 
as  an  FM  descriminator  and  is 
therefore  quite  broad- banded. 
The  output  transformer 
primaries  should  be  bal- 
anced. ■ 


IN 


3,035  MHi 


455KHz 


3.035  MHz 


OUT 


/h 


2.58MHz 


fh 


2,58  MHz 


Fig.  1 


Fig.  Z 


162 


/ 


BANDS  5  &  6 


/ 


4-4. 


/77 


fN289(4) 


V  -. 


^  7  5pF* 


^ 


TO  ANALYZER 


BANDS  1-4 


MILLER 
I2-C45 


L 


CONVERTER 


27pF 


SPRAGUE 

f IZIS   OR   IIZ21O0  OR  IIZ3I00 


V2 
GBE6 


i        \ 

22  K     ^:o.Ol^F 


Fig.  3,  *fnstail  in  receiver  as  close  as  possible  to  pickup  point. 


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164 


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f  nj 

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D.  J.  Brown  W9CGJ 
RR  5»   Box  39 

NoblesviUe  [N  46060 


DXing  with  a 
Weather  Map 


-  -  a  new 
6m  DX  technique 


Since  I  read  all  the  propa- 
gation reports,  1  decided 
it  was  about  time  to  chime  in 
my  two  cents  worth  (15  years 
worth  to  be  more  precise). 
This  is  an  article  on  the 
propagation  of  radio  waves  - 
6  meter  radio  waves  to  be 
exact.  As  anyone  can  tell  by 
my  past  VHF  articles,  I  am 
addicted  to  that  portion  of 
our  bands. 

There  is  one  BIG  factor  in 
6  meter  propagation  many 
seem  to  overlook  except  for 
some     of     its     groundwave 


effects  -  WEATHER! 

Nearly  all  large  newspapers 
cover  the  only  information 
you  really  need,  I'm  referring 
to  the  little  map  that  shows 
all  the  little  high  and  low 
pressure  cells  floating  around 
and  the  fronts  are  shown, 
too.  If  you  can  copy  the 
weather  satellites,  all  the 
better,  but  at  least  make  sure 
what  time  your  newspaper 
map  was  drawn  up  for,  as 
there  is  a  lag  from  weather 
bureau  to  news  desk,  to  press, 
to   you.    You    wilt    need   to 


just  for  that  difference,  as 
weather  is  everchanging. 

The  trick  for  single  hop 
DX  (I  know,  E  layer  and  all 
that  jazz  be  darned)  for  us 
has  been  to  find  a  low 
pressure  (storm  type  — 
mucho  electrons  excited)  cell 
about  halfway  between  us 
and  where  we  want  to  go.  If 
you  can  draw  a  straight  line 
(allowing  for  the  Earth's  cur- 
vature) from  you  to  the 
desired  destination,  and  hit 
the  Medge,f  (not  middle)  of 
one  of  these  cells,  you  are 
home  like  a  bandit.  More 
than  50%  of  my  DX  work  has 
occurred  on  a  dead  band! 
There  is  much  pleasure  in 
this,  too,  until  everybody  else 
wakes  up,  since  your  contacts 
can  be  many  minutes  long 
and  quite  rewarding  -  not 
5-9-9  contest  style. 

In   order   to   explain    the 

edge  of  the  storm  cell  theory, 
and  since  no  one  (including 
me)  seems  to  ever  remember 
it  by  the  direction  of  wind 
circulation  around  the  celt, 
let's  take  a  storm  cell  (low)  to 
your  West,  Aim  to  go 
"under11  it  as  it  appears  on 
the  map.  Example:  I  am  in 
Indiana,  target  is  California, 
and  cell  is  right  on  a  line  from 
Indianapolis  to  San  Francisco 
and  about  halfway  between. 
Aim  on  the  Los  Angeles  side, 
not  the  upper  or  Sacramento 
side.  Reverse  this  and  go 
"over"  storms  to  your  East, 
left  of  storms  to  your  North, 
and  right  of  storms  to  your 
South.  AH  this  is  with  refer- 
ence to  a  map  laid  before  you 
with  the  North  direction  to 
the  top,  which  is  the  normal. 


I  neither  know  precisely 
why  this  works,  nor  why  the 
other  side  of  the  low  cell 
doesn't  work  —  nor  does 
either  side  of  a  high  pressure 
cell  regardless  of  its  size  or 
intensity!  1  assume  it  has 
more  to  do  with  the  electrical 
charge  and  intensity  than  the 
barometric  pressure  itself. 

I  sincerely  would  appre- 
ciate hearing  any  and  all 
reports  of  success  or  failure 
using  this  method;  as  for  me 
it  has  proven  almost  90% 
effective.  Give  it  a  chance  to 
work  before  you  panic  and 
scream.  Also,  anyone  who 
believes  he  can  explain  why  it 
works  is  welcome  to  do  so.  I 
do  things  because  they  work 
and  then  figure  out  why.  just 
a  simple  explanation  will  do. 
Random  chance  for  such  an 
occurrence  is  extremely  small 
compared  to  our  success. 

Thank  you  all  for  the 
SASEs  on  past  articles  -  it 
does  assure  you  of  a  speedier 
reply  —  usually  one  day  turn 
around  unless  you  totally 
stump  me,  which  has 
happened.  There  were  over 
240  letters  on  the  article  on 
strobing  displays,  on  updating 
counters  in  general  and 
specifically  the  K20AW 
model  I  started  with.  Forgive 
me  please  the  "form"  letter 
replies,  but  they  let  me 
answer  all  but  one  of  them 
the  same  day. 

Good  DX,  and  when  the 
tow  pressure  cell  gets  very 
close  to  you  with  its  inherent 
lightning  -  give  it  up  for 
awhile  or  your  next  record 
mileage  may  be  a  QSL  card 
from  the  heavens  above!  ■ 


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166 


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PARTS  KIT  »7447       •HOOK-UP  INSTRUCTIONS 


FERRITE  BEADS  with  info  and  specs .  .  15/S1 .00 

6  hole  Balun  beads  ,,.,.... * 5/S1 .00 

SLIDE  POT-10  K  Linear  taper 4/S1 .00 


1000  uF  15  V  FILTER  CAP 


+        +       -r       -■ 


5  S1.00 


rarnsa^j  alsstrnniss 

P.O.  Bo*  4072A,  Rochester  NY  14610 

SEND  25  t  FOR  ILLUSTRATED  CATALOGUE 


Llvl-567  decoder  ...  $1 ,75 

LM-565  PLL    75 

MC  1458 75 

7490A 59 

7447  S5 

74143   3.50 

MC4024VCO 1.95 


48  HOUR  SERVICE 

Sat  is  fa  cttort  auaran 
teed  or  money  re- 
funded, NO  CO  IX 
Order*  u  ntt 
$10  00  add  S.75. 
/VV  residents  add 
?%  tax. 


R-X  NOISE  BRIDGE 


v*  Learn  the  truth  about  your 
antenna. 

!*#*  Find         its  resonant 

frequency. 

iS  Adjust  it  to  your  operating 
frequency  quickly  and  easily. 


If  there  is  one  place  in 
your   station   where    you    cannot 

risk  uncertain  results  if  is  in  your 
antenna, 

The  Pa  lorn  a  r  Engineers 
R-X  Noise  Bridge  tells  you  if  your 
antenna  is  resonant  or  not  and,  if 
It  is  not,  whether  it  is  too  long  or 
too  short.  All  this  in  one 
measurement  reading.  And  it 
works  just  as  well  with  ham-band- 
only  receivers  as  with  general 
coverage  equipment  because  if 
gives  perfect  null  readings  even 
when  the  antenna  is  not  resonant. 
It  gives  resistance  and  reactance 
readings  on  dipoles,  inverted 
Vees,  quads,  beams,  multiband 
trap  dipoles  and  verticals.  No 
station  is  complete  without  this 
up-to-date  instrument. 

Why  work  in  the  dark? 
Your  SWR  meter  or  your 
resistance  noise  bridge  tells  only 
half  the  story,  Get  the  instrument 
that  really  works,  the  Palomar 
Engineers  R-X  Noise  Bridge.  Use 
it  to  check  your  antennas  from  1  to 
100  MHz.  And  use  it  in  your  shack 
to  adjust  resonant  frequencies  of 
both  series  and  parallel  tuned 
circuits.  Works  better  than  a  dip 
meter  and  costs  a  lot  less.  Send 
for  our  free  brochure. 

The  price  is  S3?. 95  and  we 
deliver  postpaid  anywhere  In  U.S. 
and  Canada.  California  residents 
add  sales  tax. 

Italy  write  iJVTT,  P,Q. 
Box  37,  22043  Cantu,  Elsewhere 
send  S42.00  (U.5J  for  air  parcel 
post  delivery  worldwide. 

Fully  guaranteed  by  the 
originator  of  the  R  X  Noise 
Bridge,   ORDER    YOURS    NOW! 


BOX  455.  E  SCON  DIDO,  C  A  92025 
Phone:  (714)  747-3343 


168 


FOR  SALE 


li 


18  FACSIMILE  RECORDERS 

The  leading  manufacture  of  18"  FACSIMILE  WEATHER 
CHART  RECORDERS  is  now  updating  an  axisting  network  to 
solid  state  equipment.  This  updating  is  making  aval  labia  a 
number  of  16"  weather  map  recorders  ideally  suited  for  anyone 
interested  in  experimenting  with  facsimile. 

These  recorders,  with  suitable  receiver  and  FSK  converter, 
can  be  used  to  monitor  radio  weather  chart  broadcasts  as  well  as 
press  wire  photo  transmissions. 

These  recorders  are  priced  from  $50  to  $200  and  are 
available  on  a  first  come,  first  served  basis, 

Call  or  write  Mr,  Armand  D.  Bouchard 
ALDEN  ELECTRONIC  I  IMPULSE  RECORDING  EQUIPMENT  CI  INC. 

Washington  Street,  Westboro  MA  01581  (617)  366  8851 


ANTENNA  SUPERMARKET 


P.O.  Box  1682,   Largo,  Florida  33540 


DlPOLE  AND  WIRE  ANTENNA  KITS,  complete  with  Hl-Q  B ALUN,  100'  rope, 

copper  antenna  wire  and  insulators. 

80/40/15  parallel  dipoie S34.93 

40/20/15  parallel  dipoie $30.95 

BO'40  trap  d ipoie  . ... t4l .95 

40/20  trap  d i pole $36,95 


160  short,  130'  length 
SO  short,  63'  length 
40 short,  33'  length 
SmgJe  band  models  from 


■     i     -»     +     -f 


S36>95 
$31.95 
$2995 
S24.95 


VERTICALS  —  complete  with  Universal  Mounting  Base,  Folds 
to  5*  for  Easy  Transport,  Hvy.  Duty  Aluminum  Tubing. 

20/15  trap.  13'  hgt $29.95  160  compact  23'  hgt.  . . .  $44.95 

40/20/15  trap  22'  hgt,  .. .     44.95  80  compact  20' hgt  3995 

flO/40/20  *rap  30'  hgt.  .  , .     69.95  40  compact  1V  hgt  34  95 

80/40/15  trap  20'  hgt.            59.95  20/15/10  full  size  vertical  29.95 
10  meter  cov.  for  above  add  9.95 


-*** 


TOOaOER  —  tnciuo**i  »Sih.pp^g  (12  *5w*si  Coast) 
2*h0orshppm#r!t   30  d**  Quaranrte 
For  irtfo    SASE  Or  \\\  Cleii  Stamp 


NEW 

Apartment/  Porta  b  I  e 
apt.  roof  or  patio, 
camper,  trailer,  mo- 
tor  home  All  bands 
SO  10,  folds  to  5'  easi- 
ly. IT  height. 
ftO  40  20  15-10     $49.95 

tarfudr  tnlrrb*ni  —  and 
Eltpirfllwn  dale  on  Credi: 
Card  ord«i. 


We're  Fighting 
Inflation 


No  Price  Rise 


for  76 


FOB  FREQUENCY  STABILITY 
Depend  on  JAM  Oy3U"i  Our  large  stdcn  e'  Qu*ri| 
Cryi'*1   male  "at  3   end   compontntt  allure*   F*»l 
De/U*4r?  from  yj " 


CRYSTAL  SPECIALS 

Frequency  Standerds 
100KHHHC  ^3iU) 
trjOOKMHHC    6/U) 

Almost  all  CB  4el5  Tfl  or  Rec 

(CB  Synthasizar  Crystal  on  request 
Am«t«ur  Band  in  FT  2*3  t* 


14  50 

450 

12  50 


ao  Met «r 


St  so 

4J15  00 
*3  00  (1  eO^mettf  nor  4*1*1 1 


F.of  lit  clist  m«il.  add  20"  per  cryjtit  for  Airmail. 
Add  25*  Sand  check  or  money  order  Ho  deeten 
please 


Dfv.ftl 

Bob  Whan  1  Son  Electronic*.  Inc. 

2400  Cry***J  Dr„ 

Ft,  My*ri  Fl*.  MM1 

AllPhonet   {11$  i3t-2al7 

$*i*d  W  tor  rttftw  catalog 


TS-l  MICROMINIATORE  ENCODER-DECODER 

D  Available  in  all  El  A  standard  tones  670  Hz -2035  Hz 

□  Microminiature  in  size,  1.25)c2,0x,65"high 

□  Hi-pass  tone  rejection  filter  on  board 

□  Powered  by  6-16 vdc,  unregulated,  at  3-9 ma. 

D  Decode  sensitivity  better  than  lOmvRMS,  bandwidth,  ±2Hz  max,  limited 
D  Low  distortion  adjustable  sinewa ve  output 
D  Frequency  accuracy,  ±.25HzT  frequency 

stability  ±J  Hz 
D  Ehoodes  continuously  and  simultaneously 

during  decode,  independent  of  mike 

hang-up 
G  Totally  immune  to  RF 


Wired  and  tested,  complete  with 
K-I  element 

$59.95 

K-l  field  replaceable,  plug-in,  frequency 

determining  elements 

$3.00  each 


o-  o 


.sp£° 


*•* 


COMMUNICATIONS  SPECIAUSTS 

P.O.  BOX  153 

BREA,  CAUFORN1A  92621 

GUI  99S-3021 


3    -' 


,' 


169 


FREQUENCY  RANGE  220  -  225  MH* 


fi  Channel  Operation 

Individual  Trimmer*  on  all  TX/RX  Cryttalt 

AH  Cryitan  Plug  in 

12  KHZ  Ceramic  Filler 

I  Q. 7  and  4S5  KC  IF 

.3  Microvolt  Sentitlvily  far  20  dB  Quieting 

Weight-   1  lb.  14  oi+  laif  Battery 

Battery  Indicator 

Sine:  ■  ?/•  X  t  3/4  K  2  7/8 

Swrlchable  1  ft  2.9  Watt*  Output 

&  12  VOC 

Current  Drain:  RX  14  MA.  TX  500  MA 

Micro  switch  Mike  Sutton 

Unbreakable  Lexin-»>  C«m 


USES  SAME  ACCESSORIES  AS  1405 

INCLUDES 

1.2202SM 

2.  Flex  Antenna 

3.  223.50  Simplex  Installed 

328*31 


XMA  S  SPECIA  L 


FREQUENCY  RANGE  420-450  MHz 


•  i  Channel  Operation 

•  Individual  Trimmer*  on  alt  TX/RX  Cnrfla.lt 

•  All  Cryitafi  Plug  <n 

•  12  KHj  cctarnic  Filter 

•  21.4  and  455  KC  IF 

•  ,1  MicfovoH  ScniUrrlly  'Or  20  dB  Quisling 

•  Wetght    i  lb.  14  0*.  ie»  Battery 

•  Battery  indicator 

-  Sin;  I  7/t  x  1  3/4x2  7/1 

•  Switehtbte  i  ft  1,1  Watts  Output 
•  12  VOC 

•  Current  Drain:  RX   14  MA,  TX  500  MA 
■  MlCfOfwitCh  Mike  Button 

•  Unbreakable  Leu  in «  Cate 


USES  SAME  ACCESSORIES  AS  1406 

INCLUDES 

14502  SM 

2.  Flex  Antenna 

3.  446.00  Simplex  Installed 


ACCESSORY  SPECIALS 

SPECIAL 
DESCRIPTION                              PRICE 

BC1     BATTERY  CHARGER     $34. 15 

BP1     10  EA.  AA  GOULD 

N1CAD  BATTERIES  -  .  .    14,45 

BT1     EXTRA  BATTERY 

1    K  r\  T   i   §  V4  I   ■  ft>  4  4f   l-lf   ■          |i!»W 

LCI     LEATHER  CASE 

1402... 12,95 

LC2    LEATHER  CASE 

1405,  2202,  4502  ......  12.55 

SMI    SPEAKER  MIKE  FOR 
EARLY  MODEL  1402 
9  PIN  CONNECTOR  .  .  .  .24.55 

SM2    SPEAKER!    MIKE    FOR 

ALL  NEW  HAND  HELOS 
WITH  ROUND  S  PIN 
CONNECTOR  . 24.15 

TE-y  SUB-AUDIBLE  TONE 
ENCODER 
INSTALLED  ..... 34-55 

TTP    TOUCH-TONE  PAD  ....  4*. 35 

INSTALLATION  AT 
TIME  OF  RADIO 
PURCHASE FREE 

INSTALLATION  AT 

LATER  DATE,  ADD  .  .      15.00 

XF-1   10.*  KC   MONOLITHIC 

XTAL  FILTER  -                   .    5.55 

CRYSTALS 

TX  #r  nX 

(Common  Frequency 

Only) 3.7 

5 

BC-1  BATTERY  CHARGE! 

* 

"FACTORY 


DIRECT 


ONLY" 


KM  AS  SPECIAL 


aMfrarafj 


1402SM  HAND  HELD 

2.5  WATT 

TRANSCEIVER 


1405SM  HAND  HELD 

5  WATT 

TRANSCEIVER 


144-148  MHz 

3«£ 


FEATURES 


1402  SM 

*  6  Channel 
Operation 

*  Individual 
Trimmers  on  all 


1405  SM 


6  Channel 
Operation 

Individual 
Trimmers  on  all 


144-148  MHz 


Shown  With 
Opt  form} 

Touch-Tone  Pad 


r- 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I     . 

I 

I     . 

1     . 

I     . 

I     . 

I    . 

I 


TX/RX  Crystals 

TX/RX  Crystals 

■  Ail  Crystals  Plug  In 

*  All  Crystals  Pluf  In 

*  12  KHz  Ceramic 

■  12  KHz  Ceramic 

Fitter 

Fitter 

•  10.7  IF  and  455 

*  10.7  and  45  5 

KC  IF 

KC  IF 

•  .3  Microvolt  Sen- 

* .3  Microvolt  Sen- 

sitivity for  20  dB 

sitivity  for  20  dB 

Quieting 

Quieting 

•  Weight:  1  lb.  14  oz. 

*  Weight:   1   lb.  14  o*. 

less  Battery 

leis  Battery 

*  5  Meter/Battery 

*  Battery  Indicator 

Indicator 

*  Size^  a  7/8  x  t  3/4 

•  Site:  6  7/8x1   7/8 

x  2  7/8 

X  2  7/8 

•  SwitchaPle  1  &  5 

■  2.5  Watts  Minimum 

Watts  Minimum 

Output  ®  12  VOC 

Output  @  12  VOC 

•  Current  Drain  RX 

*  Current  Drain:  RX 

14  MA  TX  500  MA 

14  MA  TX  400  MA 

-  Microswitch  Mike 

(Iw)  9  00  MA  (5W) 

Button 

•  Microswitch  Mike 

*  Nfgh  Impact 

Sutton 

Plastic  Case 

*  Unbreakable 

Lexan^-  Case 

SPECIAL 

DIM  EACH  RADIO 

INCLUDES: 

Ftex  Antenna 

52/52  Simplex  Xtal 


90 

Day 
Warranty 


10  Day 

Money  Back 

Guarantee 


Can  bo  Modified 

for 
MARS  or  CAP 


_1402SM@  $159.95 
_1405SM  @  $229.95 

_2202SM@  $219.95 

-  4S02SM  @  $269.95 

-BCT  @  $34.95 
,BP1  @  $14,95 
..  BT1  @  $6,00 
-LCI  @  $12.95 
-LC2@  $12,95 
.  SMI  @  $24.95 

-  SM2  @  $24,95 
.  TE1  @  $34,95 


XIMAS  SPECIAL 

TO:  WILSON  ELECTRONICS  CORP., 

_  TTP  @  $49.95 

_XF1  @$9.95 

_  TX  or  RX  XTALS  @  $3.75  ea. 
Common  Frequencies  Only. 

FACTORY  XTAL  INSTALLATION/ 


NETTING  @$7.50/Radio 

MARS  or  CAP  XTALS  @  $10.00  ea. 

EQUIP  TRANSCEIVER  AS  FOLLOWS; 


A. 

B. 

C. 

D 

E. 

F. 


(SPECIFY  FREQUENCY 


rALS    TX 

52 

52 

v 

) 

XTALS 
G 


TX 


H. 
I. 

J.  . 
IC 
L._ 


RX 


DIRECT  SALE  ORDER  BLANK 

4288  S.  POLARIS  AVE.,  LAS  VEGAS,  NEVADA  89103 
(702)  739-1931 

□  CHECK   D  MONEY  ORDER 

DMASTER  CHARGE 

G  BANKAMER1CARD 
CARD  # 


I 


ENCLOSED  IS 


EXPIRATION  DATE 


NAME 


ADDRESS 


CITY 


STATE 


ZIP 


SIGNATURE 

SHIPPING  &  HANDLING  PREPAID  FOR  XMAS  SPECIAL 
NEVADA  RESIDENTS  ADD  SALES  TAX 

73  VALID  ONLY  NOV.  1  THRU  DEC.  31,  1976 


i 


No  Other  2  Meter 
Transceiver  Provides 
The  Features  Of  The 


Cfa/qv 


t  t*t 


urn  ux 


A 


r*«ai 


- 


wwi  w 


•143.5-148.5  MHz. 
5KHz  STEPS      •  MADE  IN  THE  USA 
35-45  WATTS   •    .25  uv  RECEIVER 
LARGE  LED  FREQUENCY  DISPLAY 
CHOICE  OF  8  POLE  OR  SUPER 

SELECTIVE  16  POLE  FILTER 
100'/.  DUTY  CYCLE 
ACCOMMODATES  MARS,  CAP,  ETC. 
COMPACT,  ATTRACTIVE,  RUGGED. 
CLEANEST  TRANSMIT  SPECTRUM 
INTERMOD  IMMUNE  RECEIVER 


Direct  from  C^W  only 

Phone  toll  free  for  brochure 
or  to  order  your  FM-DX ! 


FM-DX  complete  with  mike  and  accessories  -  S599.00 

or  with  16  pole  super  filter  -  S 6 50, 00 
MASTERCHARGE  &  BANKAMERICA  CARDS  WELCOME 

(Please  add  2%  on  credit  card  purchases, 

we  pay  shipping  on  orders  accompanied  by  check  or  money  order  ) 

CommuEiicatifini  Corp. 


208  Center i He  Road,  Lancaster.  PA  17603 

Toll  free  sales  &  services    Phone  (800>  2310250 

In  Pa,  call  (717)  299  7221  (collect) 


- 


■>■  Z*"^^   "-V-*,    J~*~~*  """^  ^  ' 


ifi*.    j#h     jtr& 


HAM'S  ALMANAC 


*  For  early  December  shipment  Orders  received  prior 
10  Dec  WiElbe  hekjfor a  single tiulk  shipment  Allow  4 
to  6  weeks  for  delivery 


Approximately  8'  _■  ■■  11  inches,  opens  to  1 7  * 
1 1  <n  calendar  format  with  hole  for  hanging 

Brand  new  monthly  cartoons  by  Les 
Funslon,  WA6HJL —  Propagation  forecasts 
by  Prof  OstermondTor.  ex-YM4XR  who 
hopes  to  better  his  claimed  70%  accuracy 
with  new  techniques  —  OSCAR  data  — 
Frequency  allocations  —  Memorable  events 
1 9SS-1976  —  ■"Frame  H"  project  —  and  more 

Price  S3  00  postpaid  via  3rd  class  mail 

Label  &  postage  affiled  di  reel  ly  locoter  Add  75C  for 
shipment  in  envelope  via  1st  class  mail 


Alkan  Products 

Box  3494  •  Scottsda/e,  Ariz  85257 


THE  NEW,  IMPROVED 
'ORIGINAL  BRIDGE'! 


aifc 


\v<\ 


$21.95 

ADO  S1.50  FDR  POSTAGE) 

Reads  forward  power 

and  SWR 

simultaneously. 

Handles  full  legal  limit 

Usable  3  thru  150  Mhz. 

Small  enough  for 

mobile  use. 


Quement  Electronics 

1000  So.  Bascom  Ave. 

San  Jose,  Ca  95128 

CALIFORNIA  REStD£NfS  ISO  SUES  Til 


172 


Social  Ei/ents 


DALLAS TX 
NOV  5-7 

Trie  First  Southwest  Vintage  Radio 
&  Phonograph  Convention  win  be 
sponsored  by  the  Southwest  Vintage 
Radio  &  Phonograph  Society  on  the 
5th,  6th  and  7th  of  November  at  the 
Ramada  Inn  Dallas  East  in  Dallas, 
Tescas.  Planned  activities  include 
forums  on  collecting  of  antique  and 
vintage  radios,  restoration  of  antique 
radios,  classic  radios  (McMurdo- 
Silver/ScotU.  antique  phonographs, 
and  general  Q&A.  The  usual  banquet, 
swap  sessions,  and  an  auction  will  also 
be  held.  Of  special  interest  will  be  a 
contest  of  various  equipment  sub 
milted  by  convention  registrants. 
Three  priies  will  be  awarded  in  each 
division,  In  addition  a  "Best  of  Show" 
award  will  also  be  made.  For  more 
information  and  a  pre -registration 
packet,  please  contact  Convention 
SVRPS,  PO  Box  19406,  Dallas  TX 
75219, 

JVIcAFEE  NJ 
NOV  13-14 
The  1976  Hudson  Division  Conven- 
tion will  be  held  November  13-14, 
1976  at  the  Great  Gorge  Resort  Hotel 
in  McAfee,  New  Jersey.  There  will  be 
ARRL  and  FCC  forums,  large  indoor 
exhibit  area  with  40  booths,  giant 
outdoor  flea  market,  super  raffle,  free 
gifts,  special  features,  indoor  swim- 
ming, game  room,  and  much  more. 
Registration:  advance  S3,  at  door  $4. 
For  hoief  registration:  A I  Piddington 
WA2FAK,  4  Acorn  Drive,  East  North- 
port  NY  11731. 

LIVINGSTON  NJ 
DEC  3 

The  Livingston  Amateur  Radio 
Club  will  ho  id  its  second  annual  elec- 
tronic flea  market  on  Friday,  Decem- 
ber 3,  at  7:30  pm  at  the  Livingston 
Memorial  Recreation  Building.  For 
further  info,  contact  Jeff  Gehl 
WN2AXL.  (201 J-267-02S0, 

BROOKLYN  NY 
DEC  19 

The  Kings  County  Repeater  Asso- 
ciation will  hold  an  indoor  flea  market 
on  Sunday,  December  19,  1976,  from 
9  am  to  4  pm.  Located  at  910  Union 
Street,  Brooklyn  NY  (at  Grand  Army 
Plaza).  Sellers  $3.00,  buyers  S1r 
children  free,  Refreshments  available. 
Tdlk-in  on  146.43  and  146.52. 

DAVENPORT  I A 
FES  27 

The  annual  Davenport  Radio 
Amateur  Club  Hamfest  will  be  held 
Sunday,  February  27,  1977  at  the 
Masonic  Temple  m  DavenporL  lowa. 
Admission  is  $1.50  advance  -  52.00 
at  the  door.  Talk  in  on  28/88  and  52. 
Refreshments  and  tables  are  available. 
For  info  and  tickets  send  SASE  to 
Dick  Lane  WA0GXC,  116  Park 
Avenue,  So.  Eldridge  I A  52748, 


FORT  WALTON  BEACH  FL 
MAR  20 

The   Fort  Walton  Beach  Swapfest 
will  be  held  Sunday,  March  20,  1977 
For  further  information  contact  Play- 
ground Amateur  Radio  Clubr  PO  Box 
873,  Fort  Walton  Beach  FL  32548. 


EDITORIAL 


from  page  71 

would  go  almost  mad  to  be  around 


that  much  in  goodies.  8080s?  Oh  yes, 
here  is  a  carton  of  several  thousand. 
Memory  chips?  They're  over  there  in 


DOUBLE  BAZOOKA 
DIP0LE 

GTO 

Randy  to  use  broadband  dlpoJe  com- 
plot*  with  central  Insululor  unci  SD239 
r'TtriQtitor  end  Insula  Lor  completely 
water  proof  cap.  1000  wattn^  specify 
curitcr  frequency,  SO  rtwtt**  —  £29.50* 
to  15    meter   —   S27.50f   20    moter  — 

lia.BO. 

4  band  trap  dipote  KIT  coropkte, 
includes  SO-40  Lrap  central  And  end 
iiiiuJ.iTi.r  dfttfeimf  win",  HHI  fWd  of 
Rfi&g,  I-PI2&9  connect  «f  unci  instnic* 
lion  sbtei  .  .  .s 35.00 
J-  iWrtlass  central  insula  tor  limilv  to 
photo  abdrt.   1000  lb*  i«t  ?5  95 

PPd    JAC  TENNA  ELECTRONIC 
13850  Victor  in 
Tracy  Quebec,  Canada 


cs 


dcSilicon  Retro-fit  Rectifiers 


FEATURING: 

•  Voltage  ratings  up  to  65,000  volts 

•  Current  ratings  up  to  1.25  amps 

•  Fully  giasslvated  diode  buNding  blocks  by  — 

GENERAL  ELECTRIC 

•  Replacement  types  including  — 


Typfl  No. 

i 

dc3B24 

17,00 

dc3B28 

12.00 

dc3R29 

16,00 

dc5R4 

5,10 

dc5U4 

165 

rJcSW 

3.65 

dcsn 

3-50 

Typi  No, 

f 

dc5Z3 

3,65 

dc5Z4 

3  65 

dc£AX5 

3,55 

(4c6X4 

4.85 

dc25Z6 

4.00 

ticBO 

435 

dc25QR 

7500 

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dc37W 

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QCOtAJB 

dc8Q20 


31.50 
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IZOO 
15.50 
BSJ 
4100 


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Poit  Office  B*x  No,  8)6  Woyri*,  N.  J.  07470 

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With  the  Metrum,  one  Vanguard 
synthesizer  covers  both  transmit 
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SERVING  THE  INDUSTRY  SINCE  1  922 


173 


thai  stack  of  cartons.  One  of 
Godboui  s  most  popular  items  is  a  4K 
memory  board,  and  we  got  a  promise 
from  Reo  Pratt  for  an  article  on  it  tor 
Kilobyte. 

Qiil  and  Reo  drove  us  over  to  see 
George  Morrow  ,  ,  .  an  incredible 
genius.  He  was  hard  at  work  on  a 
whole  bunch  of  projects  ...  the 
Godboui  PACE  computer  system 
{working  just  fine  and  ready  for  pro 
ductlon)   . . .  a   front   panel   for   the 


Attair  and  tmsai  with  a  fantastic  oper 
ating  system  built  into  it  .  .  and  a 
bunch  of  other  projects.  George 
promised  articles  on  the  PACE,  an  his 
front  panel,  on  stopping  a  computer, 
on  his  secret  prototyping  system.  Now 
if  we  can  only  get  him  to  stop 
building  long  enough  to  write! 

Bill,  Reo,  George,  Sherry  and  I  got 
in  Bill's  plane  and  flew  out  to  Santa 
Rosa  for  dinner,  I  spent  most  of  the 
time  rag  chewing  on  2m  with  my  HT. 


Bill  had  bought  the  plane  up  here  in 
New  Hampshire  last  spring  and  taken 
if  back  10  Oakland.  They  originally 
tried  to  get  me  to  buy  the  plane  lit 
was  a  very  good  deal),  but  I  am  too 
careless  a  pilot  and  if  I  started  Flying 
again  I'd  kill  myself  for  sure,  I  sold 
my  last  plane  when  I  needed  money 
to  put  out  the  first  issue  of  73  ,  ,  ,  in 
1960.  I  had  a  lot  of  adventures  while  I 
had  my  plane. 

Down   in    LA.   we  visited   Dennis 


PHONE  PAD  $6,50 

New,  packaged  by 
Automatic  Electric. 
Preferred  by  many  over 
the  tactile  pads.  Great 
for  repeaters,  auto- 
dialers,  etc. 


n 

2 

13 

4 

5 

6 

'7 

e 

I*" 

N 

0 

o 

SP  213A  S6.50  ea  3/S16.00 


SPEED  CONTROL 

New  solid  state  SCR 
speed  control  for 
AC/DC  devices  or  resis* 
tive  loads,  lights,  etc. 
Good  for  a  whopping 
1.2  KW,  Ideal  soldering  iron  control. 

SP-189A  S4.50  ea  3/S12.00 


5  VOLT  1  AMP  REGULATED  power  supply  kit  for  logic  work.  All  parts  including 
LM  309K  .. rfK-7  $7,50 

DUMMY  LOAD  resistor,  non-inductive,  50  ohm  5  watts $1.00 

AA  NICAD  CELLS  brand  new,  fine  biz  for  handy  talkies..-..,..,....  $1.25  ea  9/S9.00 

SUB-C  SIZE,  slightly  smaller  than  C  but  substitutes  in  most 

usage  by  use  of  spacer New  Gould,  $1 ,35  ea,  10  $12.00 

ASCII  KEYBOARD  brand  new  w/ROM  chip,  data  package ........$45.00 


UNIVERSAL  POWER  SUPPLY 
A   unique   plug-in  supply  by  Panasonic.   Useful  for 

calculators,  small  radios,  charging  many  &  various 
small  NiCad  batteries.  Adjustment  screw  plug  on  the 
side  changes  output  voltage  to  47?,  6,  l%t  or  9  volts 
dc  at  100  mA.  Output  cord  with  plug,  6  ft.  long. 
#SP-143C  $4,50  3/51  2. 


LASER  DISCHARGE  CAP 

Sangamo,  new,  40  mfd  3,000  volts,  180  Joules.  May 
be  used  for  filtering,  linears,  etc.,  by  derating  to 
2,000  volts.  Shipping  wgt.  10  lbs.  Measures  3%  x4% 
x  9%  inches.  S25  00  each  5/$1 10.00 


TELEPHONE  TOUCH  PADS 

New,  by  Chromerics,  standard  telephone  format. 
Measure  214  x  3  inches.  Great  for  repeaters,  phones, 
computers,  etc.  S4.50  each  6/525,00 


VIDEO  TAPE  HEADS 

Brand  new  from  Cartravision  home  video  equipment. 
Made  for  1/2  inch  tape.  Includes  erase,  play,  video  and 
matched  set  of  3  record  heads.  Total  of  5  heads.  Made 
by  Vikron,  Bogen,  etc.  S60  value.  ^SP  240 A  S5.00. 


a 


^. 


yWe&nMc* 


Please  add  shipping  cost  on  above, 

P.O.  Box  62 

E.  Lynn,  Massachusetts  01904 


FREE  CATALOG 

SP  8  NOW  READY 


Brown  of  Wave  Mate.  This  is  ihe  wire 
wrapped  computer  . ,  P  and  it  is  a  bit 
more  expensive  than  most  of  the 
others  so  business  wasn't  quite  as 
hectic  as  for  some.  I  suspect  that  once 
Dennis  gets  his  ideas  across  there  will 
be  a  lot  more  enthusiasm  for  both 
wire  wrapping  and  For  the  Wave  Mate. 
There  wilt  be  some  article?  by  him  on 
bath  wire  wrapping  and  on  the  design 
concepts  at  the  Wave  Mate,  There  may 
be  a  Wave  Mate  in  your  future  .  , . 
watch  out. 

John  French  of  The  Computet  Mart 
in  Orange  has  been  doing  fantastically 
with  high  Lear  Sjegler  terminals  and 
was  putting  the  finishing  touches  on  a 
16-bit  computer  system  which  will  be 
introduced  shortiy.  Naturally r  we  got 
a  promise  of  an  article  on  it  for 
Kilobyte.  Just  what  the  computer 
hobbyist  reaction  to  the  coming 
16  bit  systems  will  be  is  quite  a 
question.  They  probably  don't  need 
the  speed  and  computing  ability  of 
such  a  machine,  but  I'll  bet  they  will 
go  for  it  anyway. 

My  next  stop  was  in  Salt  Lake  to 
see  how  Sphere  was  doing  They've 
been  having  quite  a  bit  of  trouble  .  .  . 
m  part  due  to  a  credibility  gap  on 
promised  software  .  .  ,  partly  due  to 
parts  problems  .  ,  .  documentation 
delays  .  .  .  etc,  The  new  president, 
with  whom  I  had  an  appointment,  was 
not  available.  Doug  Hancy  gave  us  a 
tour  of  the  building  and  promised  that 
a  system  for  our  lab  would  be  shipped 
immediately. 

Next  month:  on  to  Albuquerque 
and  the  Mighty  MlTS  Machine! 

NEW  AND  BETTER  CHIPS 

There  is  a  lot  of  excitement  over 
the  Zilog  Z  80  microprocessor  chip.  It 
is  an  advanced  version  of  the  Intel 
8080  .,,  much  more  flexible,  I  view 
this  with  very  mixed  emotions  ...  on 
the  one  side  I'm  enthused  about  being 
able  to  put  aside  my  nice  $650  CPU 
with  the  8080  and  put  in  a  new  Z  80 
CPU  which  will  probably  run  another 
S6 50  or  so.  Ill  overtook  the  fact  that 
I've  barely  been  able  to  get  the  old 
computer  system  working  king 
enough  to  do  much  with  it 
certainly  not  long  enough  to  develop  a 
large  number  of  programs. 

I  suspect  that  the  Z-30  means  that 
much  of  the  small  computer  industry 
is  going  back  to  square  one  as  far  as 
programming  is  concerned.  While  ii  is 
nice  that  the  Z  80  will  work  with  the 
8080  programs  (not  completely,  I 
understand  .  .  ,  hut  for  the  most 
pan  J,  I  also  understand  that  no 
serious  programmer  would  ever  put  up 
with  using  8080  programs  on  the  Z  80 
...  It  isn't  efficient.  No,  they'll  go 
back  and  write  new  compilers  for 
BASIC  -  . .  and  that  might  take  as  long 
as  last  time, 

The  Altair  8800  first  came  out  in 
January,  1975.  Their  BASIC  compiler 
was  debused  and  out  about  a  year 
later  ,  .  ,  and  we  are  still  waiting  for 
much  in  the  way  of  application 
programs  for  the  system.  The  fact  ts 
that  it  takes  a  long  time  to  write 
programs.  The  6800  came  out  along  m 
late  1975  and,  as  far  as  I  know,  there 


174 


is  not  yet  a  BASIC  compiler  available 
for  it  that  is  full  sized.  There  are  a 
couple  for  Tiny  BASfC  or 
Micro- BASIC  .  .  .  and  others  are  to  be 
ready  soon.  There  is  less  than  that  for 
the  other  systems  which  have  come 
later, 

So  here  we  go  back  again!  And 
when  the  Z-SO  comes  along  next 
January,  wtli  we  do  another  memory 
dump  and  start  still  again?  Or  will  it 
be  the  Intel  8838  that  gets  everyone 
all  excited  next  year  ...  or  the  year 
after?  There  is  much  to  be  said  for 
sticking  with  the  good  old  8080  and 
working  out  programs  so  that  we  can 
use  it. 

Space  is  available  for  conflicting 
viewpoints,  as  they  say  on  TV. 

WO  WAY  TO  TURN 

The  old  "tube"  hams  are  getting 
very  nervous.  The  rash  of  articles  in 
73  bringing  us  all  up  to  speed  on 
modern  technology  .  «  ♦  the  large  scale 
integrated  circuit  and  its  main  result, 
the  microprocessor,  has  sent  some 
into  shock  . .  -.  others  to  the  midnight 
oil  to  try  and  catch  up.  The  "I  just 
don't  want  to  know  about  it"  crowd 
(3999  kHz,  e.g.)  thought  they  had  an 
out  .  .  .  until  their  last  inner  sanctum 
of  protection  against  the  onrush  of 
progress  dumped  on  them  with  a 
series  of  articles  on  .  .  .  micro- 
processors! 

Other  than  canceling  subscriptions 
to  everything  but  CQt  there  is  no  way 
out.  The  initial  reaction  was  of  utter 
panic  ,  .  .  computers  are  not  any  part 
of  amateur  radio  and  they  will  have  to 
go  away  ,  .  .  right? 

Speaking  of  CO  .  ,  .  has  anyone 
seen  it  on  the  newsstands  anywhere? 
It  used  to  be  sold  by  newsstands,  but  I 
haven't  seen  it  in  a  couple  of  years 
anywhere,  I  think  73  3s  the  only  ham 
magazine  being  sold  on  newsstands 
these  days. 

If  you  happen  to  run  into  aid- 
timers  suffering  from  future  shock 
and  who  want  to  get  into  at  least  a 
speaking  acquaintance  with  micro- 
computers, the  new  73  book  "Hobby 
Computers  Are  Here!"  is  the  only 
book  out  which  will  help  make  the 
transition  relatively  painless,  $4,95 
from  the  73  Radio  Bookshop. 
Engineers  may  get  some  value  out  of 
the  HR  series  of  reprints  from  a 
scientific  journal  on  microprocessors. 
So  far,  about  90%+  of  the  original 
material  on  the  subject  has  been 
published  in  73  .  ♦ .  shades  of  the  old 
FM  days  seven  years  ago. 

WILL  KILOBYTE  ROB  I/O? 

It  appears  as  if  Kilobyte  Is  going  to 
be  a  lot  more  software-  and  systems- 
oriented  than  the  I/O  section  of  73r  so 
1  expect  that  I/O  will  be  carrying  on. 
We've  covered  a  lot  of  the  computer 
fundamentals  in  73  already,  but  we 
still  have  more  to  go.  And  we  surely 
are  going  to  have  a  lot  of  ham 
applications  of  computers  in  73. 
Hopefully,  once  the  basics  of  the  field 
are  published  in  73,  we  won't  have  to 
go  back  over  them. 

Authors  with  ham  applications  for 


computers  should  run,  not  walk,  to 

their  typewriters. 

ATLANTA  1977 

The  Atlanta  Hamfest  is  being 
expanded  this  coming  year  to  include 
a  Computerfest.  The  Hamfest  will  be 
centered  on  Saturday,  June  18th  and 
the  Computerfest  on  Sunday,  June 
19th.  This  will  be  the  big  hamfest  and 
computerfest  for  the  southeast  for 
19  77,      so     plan     your     vacations 


accordingly, 

Atlanta  is  a  great  city  for  something 
like  this  since  there  is  so  much  enter- 
tainment for  the  family  .  .  ,  they  don't 
have  to  stand  around  whining  while 
you  take  a  close  look  at  the  latest 
equipment.  Stone  Mountain  will  keep 
them  occupied  for  at  least  a  day  .  .  , 
they'll  enjoy  the  excitement  of  a  ride 
on  the  railroad  around  the  mountain. 
Then  there  is  Underground  Atlanta 
,  .  .  complete  with  a  computer  which 


will  print  out  your  portrait  on  a 
Teletype  machine!  Atlanta  has  a  lot  to 
offer. 

In  addition  to  about  80  exhibits  by 
ham  dealers  and  manufacturers,  there 
are  expected  to  be  about  50  or  so  by 
computer  firms  .  .  .  and  perhaps  the 
biggest  flea  market  yet  for  both  ham 
gear  and  computer  equipment.  You'd 
better  make  your  reservations  early  so 
you'll  be  right  in  the  middle  of  the 
action. 


FAX  MACHINE  BY  DATAFAX 

We  have  transmitters  and  receivers.  Used  for  weather 
charts,  hi  speed  teletype  recording.  Normally  used  over 
the  phone  lines.  Operational  when  removed  due  to 
upgrading  of  equipment.  Only  a  few  on  hand  and  sold 
"AS  IS."  When  used  over  the  phone  lines  from  weather 
data  system,  will  draw  full  map  of  the  US  with  cloud 
cover  and  also  pressure  gradients.  Due  to  the  weight  of 
these  machines  they  must  be  shipped  via  truck  as  they 
are  around  60  lbs.  Made  for  desk  top  use.  Made  by 
Steward  Warner  Elect,  Picture  is  typical  unit.  When 
ordering  state  receiver  or  transmitter.  #FAX  $125.00 
FOB  Lynn  Mass. 


PARITY  DETECTOR 

New  packaged,  made  for  RCA,  detects 
even  or  odd  parity,  baud  rate  110f 
150  or  134.46,  Built-in  logic  supply 
for  the  ICsr  operates  from  standard 
115  Vac,  Control  panel  allows  manual 
or  automatic  reset  mode  of  operation. 
Aluminum  enclosure  (not  shown) 
covers  the  electronics.  TTY  com- 
patible. Ship  wt.  10  lbs.  $16.50 


0 


■ 


i%*s- 


GENERAL  PURPOSE  POWER  SUPPLY 

A  well  designed  transistorized  regulated  power 
supply  with  many  uses.  Each  voltage  adjustable 
by  a  pot.  Each  voltage  fused.  115  volts  AC  60 
cycle  input.  Output  (minus)  12  volts  at  1/3  Amp, 
12  volts  (plus)  at  3  Amps,  6  volts  at  1  Amp  , .  , 
three  output  voltages.  Many  uses  ...  as  battery 
charger,  op  amp,  5  volt  logic  supply,  operate 
your  car  radio  or  tape  player,  CB  set,  in  the 
house,  etc,  A  commercially  built  regulated 
supply  for  far  less  the  price  of  a  kit. 
Shipping  wgt,  10  lb.  #SP-152*L  $17.50 


SILICON 

SOLAR 

CELL 

shown  actual  size 


yfte&nMQ^ 


SOLAR  CELLS 

Designed  for  the  space  program, 
these  are  the  highly  efficient 
silicon  high  output  cells.  Used 
for  powering  equipment,  charg- 
ing batteries.  Made  by  Ion 
Physics  Corp.  Each  with  spec 
sheet. 

Size  .394  x  .788"  65  mA,  .43  V 
$1.25  12/51 Z0G 
Size  .788  x  .788"  125  mA,  .43 
V$1.60  127S15.00 


ZENER  15V  63  Watt  $1.00 
2.5  Amp  1,000  piv 

diode .„4/$1,00,  25/S5 

Motorola  1N4001  diode  1A, 
50  piv  ........ 20/$1.00 


Pfease  add  shipping  cost  on  above. 

FREE  CATALOG   SP-8  now  READY 

P.O.  Box  62     E.  Lynn,  Massachusetts  01904 


J 


175 


from  &age  4 


EDITORIAL  BY  WA  YNE  GREEN 

for  protecting  our  low  bands  twe've 
already  lost  almost  all  of  our  VHP  and 


UHf  bands)  is  to  get  one  or  more 
teams  of  top- notch  ham  ambassadors 
out  there  to  sell  amateur  radio  to  the 
smaller  countries. 

The  obvious  way  to  do  this  is  to  get 
the  ARAL  directors  off  their  duffs, 
and  have  them  reach  into  the  League 
pocket  and  get  people  like  Bill  Eitel  or 
Lloyd  and  Iris  Colvin  out  there 
visiting  these  important  countries.  The 
League  has  over  51,000.000  just 
sitting  around  in  cash  and  securities, 


HITEHOUSE&CO. 

17  Newbury  Drive,  Amherst,  N.H.  03031 


■ 


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Johnson  1 54-50?  Dual  200  pF  k  V  .. 46.20  ^K^W* ^** 

i  COUNTER  DIAL  ■iv- 

Millen  10031,  0-99  tarns  readout  with 
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HAMMARLUND  SINGLE  SECTION  T9AG  .50  T37-6  .25 

1200  V  T80-2  .40  T37  10  .25 

uTmcir  ^n.r  M^n  TS0"3  40  T37-12  .25 

MC20S3.5   20PF  $8.40  T682  35  J2S2  20 

MC35S60   35pF  8.50  T683                35                 T25  12                   .20 

MC  SOS  65  -50  pF  8-60  T68-6               ,35                 T12-2                      .15 

MC75S8.0  80pF  8-80  T50  2               .30                 T12-2                      !l5 

MCI  00s  8.3-100  pF  9.30  T50-3               .30 

MC  1 40S  1 0  -1 40  p  F  9.40 

MILLEN   SINGLE  SECTION  800  V  *****  Toroidal  Cor« 

19100  8- 100  PF  S11.40                           *£                             j£                              - 

19140  9.7  148  pF  12,00                            FT-SO-72                    ,35 

19335  T5    339  pF  17,15                            ft  B2  61                     AQ 

J.W.MILLER 

„  .__  ..    ^  _  _,      ^  ~t,    .a  Ferrrtff  Shading  Bands 

1460-1   3gang  6-21  pF  $6.48  s-ze  Pf|CD 

2101    Igang  11    l05pF                      18.00  F6-73-101  £1.00  Do** 

Many  other  values  from  these  designs  FB-43-1Q1  1.00  Do/, 

in  stock.  FB-73-801  1.50  Do*, 

NOW    IN    STOCK  FB-43-801  1.50  DO,. 

Transmitting  Variables  Roller  Inductors  —  Counter  Dials  -  Air  Wound  Coils  -  Couplings  — 
Knobs  -  Receiving  Variables  -  Toroids  -  R,F.  Chokes  -  CoO  Forms  and  more  from  Millen - 
E.  F.  Johnson  -  Barker  &  Williamson  -  JW  Miller  -  Hammarlund*  Send  First  Gass  Stamp  for 

1  iywc     Add  $2.00  to  each  order  for  shipping  and  handling.  Prices  subject  to  change. 


which  should  be  out  there  working  for 
the  hobby.  Perhaps  it  is  time  for  the 
members  to  insist  thai  the  Miser  of 
Newington  stop  hoarding  money  for 
some  rainy  day  and  check  the  storm 
clouds  which  are  brewing. 

Several  years  ago  the  board  of 
directors  set  aside  a  $100,000  slush 
fund  for  "protecting  our  frequencies/' 
Money  gets  spent  out  of  this  fund 
every  year,  but  so  far  no  accounting 
of  these  expenditures  has  ever  been 
made  to  the  members.  The  hundred 
thou  would  probably  do  the  [ob  we 
need  done  —  if  it  were  used  honestly. 

So  what  can  you,  the  ARRL 
member,  do?  You  can  pin  down  any 
ARRL  director  who  shows  his  face  at 
your  club  or  at  a  hamfest  and  insist  on 
getting  an  accounting  of  your  money. 
Insist  that  he  tell  you  exactly  how 
that  hundred  thou  has  been  used  in 
the  past,  or  vote  him  out  of  office. 
Don't  blame  the  officials  too  much 
...  the  money  was  there  and  they 
thought  there  would  be  no  accounting 
to  the  members  for  it,  so  they  did  just 
what  you  might  expect. 

If  your  director  levels  with  you 
about  the  corruption,  and  promises 
not  only  to  end  it  but  to  see  that 
something  is  done  immediately  in  the 
way  of  serious  WARC  I  ITU}  prepara- 
tion, then  perhaps  you  can  forgive 
htm  for  being  part  of  the  coverup  and 
elect  him  again. 

Lloyd  and  Iris  Colvm  would  be 
ideal  ham  ambassadors  > .  .they  know 
the  values  of  amateur  radio  to  small 
countries  . .  .  they've  been  just  about 
everywhere  in  the  world,  and  they  are 
about  as  nice  people  as  you  will  ever 
meet.  Lloyd  was  being  considered 
seriously  for  president  of  the  League  a 
few  years  backp  and  I  think  that  one 
of  the  most  serious  mistakes  the 
directors  have  made  in  recent  times 
was  in  giving  In  to  Huntoon  and 
electing  his  crony  Daniels. 

We  have  but  two  years  left  to  beat 
the  bushes  for  votes  among  the  smafl 
countries  ,  .  ,  are  you  going  to  let  this 
conference  go  the  way  ARRL  did  the 
last  one,  when  we  lost  64,492  MHz 
out  of  our  UHF  allocated  64,495 
MHz?  That's  right  ...  we  went  into 
the  last  conference  at  the  ITU  and  lost 
99.995%  of  our  UHF  satellite  frequen- 
cies. If  you  don't  put  the  pressure  on 
your  director  and  do  it  right  now,  you 
could  be  doing  great  harm  to  one  of 
the  most  valuable  human  resources 
our  country  —  or  any  other  country  — 
has  ...  radio  amateurs,  Elect  directors 
who  will  break  the  cobwebs  on  the 
Newington  purse  and  get  us  all  out  of 
this  fix.  Let's  put  some  of  that  million 
bucks  to  work  while  there  is  still  time. 

IT  MAY  BE  A  FIGHT 
Since  Baldwin  (he's  running  things 
now)  permitted  the  board  of  directors 
of  the  ARRL  Foundation  to  resign  in 
protest  rather  than  permit  that  organi- 
zation to  try  and  help  with  the  WARC 
effort,  it  seems  more  than  likely  that 
he  will  do  everything  he  can  to 
prevent  the  directors  from  pursuing 
the  same  goals.  I'll  bet  you  haven't 
heard  about  that  fiasco  Irom  your 
director  either  ,  .  .  most  of  them  are 


176 


sitting  on  top  of  that  bomb  and  don't 
know  what  to  do  about  it. 

Being  an  ARRL  director  may  have 
prestige,  but  it  offers  little  f un.  Most 
of  them  are  afraid  to  talk  with  other 
directors,  for  they  never  know  which 
one  will  report  it  to  Baldwin  and 
make  them  suddenly  "the  enemy/' 
Directors  are  supposed  to  show  up  at 
one  or  two  meetings  a  year,  vote 
unanimously  yes  or  no,  and  not  ask 
too  many  questions.  Other  than  that, 
they  have  to  go  to  club  meetings  and 
hamfests  in  their  area  and  pass  along 
the  "word"  from  HQ.  Members  keep 
this  system  going  by  re-electing 
directors  for  years. 

Perhaps  it  is  unreasonable  of  me  to 
measure  the  interest  of  a  di recto r  by 
whether  he  gets  73  or  not * .  *  but  how 
can  anyone  really  be  in  touch  with 
things  if  he  doesn't  read  731  \  just 
checked,  and  seven  of  the  15  directors 
are  not  subscribing,  If  you  run  across 
HallerP  Egbert,  Zak,  Sullivan, 
Thurston,  GmeHn  or  Price,  you  might 
mention  the  terrible  things  you  saw  in 
73  about  them  .  .  .  drive  them  crazy. 

Half  of  the  directors  are  up  for 
grabs  every  year,  so  you  can  change 
things  if  you'll  take  an  interest.  Get 
someone  you  can  trust  to  run  for  the 
job  and  get  him  elected.  There  were  a 
lot  of  posters  at  the  Chicago  ham f est 
for  Don  Miller  W9NTP  to  replace 
Haller  , .  .  that  would  be  a  great 
change.  Don  is  the  SSTV  pioneer,  not 
the  DXpeditioner  who  almost  ruined 
DXing.  In  most  cases  you  can't  go  too 
far  wrong  by  getting  someone  new. 

INFLATION  AND  SUCH 

Those  few  really  brainwashed 
ARRLers  who  fell  for  the  "more  is 
less"  baloney  last  year  and  believed 
that  a  bigger  OST  would  cost  less  are 
having  to  face  up  to  the  facts  of  life 
.  . .  which  are  just  as  I  predicted  \n  73. 
QSTs  costs  have  gone  up  substantial  I y 
.  . .  and  so  have  the  costs  of  all  the 
other  ham  magazines  .  .  .  the  result  of 
the  new  size.  Well,  the  new  size  is  here 
and  it  isn't  going  back  again.  Most  of 
the  magazines  have  had  to  change 
printers  in  order  to  match  the  new 
size  to  bigger  presses. 

QST  has  announced  their  new 
advertising  rates  ...  up  to  $912  for  a 
page  now.  7J$  rates  are  $1095  for 
one  page.  The  latest  rate  we  have  for 
HR  is  $695,  and  CQ  is  $575.  Since 
advertising  rates  are  based  largely  on 
circulation,  this  may  tell  you 
something- 

Apparently  the  recent  rise  in  73 
readership  has  some  people  worried. 
ARRL  Is  running  a  poll  of  their 
members  to  find  out  what  it  is  about 
QST  that  they  don't  Irke,  If  you  get 
oneh  please  don't  forget  to  tell  'em 
how  much  you  really  enjoy  and  look 
forward  to  the  SCM  reports  and 
contest  results  .  . .  okay? 

The  1976  cover  price  for  the  ham 
magazines  has  been  $1  for  ail  but  73 
.  .  .  which  at  $1.50  has  been  the  best 
selling  by  far  on  newsstands  and  over 
radio  store  counters.  We  understand 
QST  is  increasing  to  $1.50  in  January 
.  ,  .  no  word  on  HR  or  CQ<  73  will  go 
up  to  $2  in  January  and  the  yearly 


subscription  rate  will  go  up  to  $12.50, 
with  $25  the  price  for  three  years. 
You  say  you  forgot  to  send  in  the 
$1 7.76?  That's  the  way  it  goes. 

LIFE  ON 
TIME  PAYMENTS 

A  life  subscription  costs  $150  these 
days.  That's  a  little  heavy  for  most 
people,  so  we'll  go  along  with  a  five 
payment  system  .  .  .  $30  per  payment 
for  five  months.  The  life  subscription 


is  a  good  deal  . . .  not  a  few  73 
subscribers  bought  in  years  ago  and 
have  been  sailing  free  for  a  long  time. 
You  know  that  inflation  is  not  going 
to  stop  .  .  ,  thai  paper  and  postage  are 
going  to  keep  going  up  ...  so  grab  this 
bargain  while  you  can.  Just  send  $30 
and  a  note  that  you  want  to  be  a  lifer. 

RECENT  MANIFESTS 

Let's  see  .  .  .  somehow  we  managed 
to   survive  an   ARRL   convention    in 


Philadelphia  . .  .  right  in  the  middle  of 
the  American  Legionnaires  who  were 
dropping  like  flies.  Our  73  booth  was 
constantly  surrounded  by  them  all 
weekend.  Few  hams  had  to  worry 
about  getting  sick,  since  they  stayed 
away  from  the  convention  by  the  tens 
of  thousands. 

The  Boston  convention  pulled 
about  what  I  expected  for  a 
downtown  Boston  affair  .  .  .  not  very 
much.  I  was  on  the  speaking  program 


HITEHOUSE&CO. 

17  Newbury  Drive,  Amherst,  N.H.  03031 


Give  your  transmitter  its  best  Christmas  yet. 
Give  it  the  best  transmatch  yet! 


BUGGED 


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•  Transmatch  Jr 

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for  DELIVERY  BEFORE  CHRISTMAS. 

Serious   about  antennas?   Then   you   will  want  to  know  about  the  new  Miilen 
impedance  bridge.  Write  for  details. 

JAMES  MULLEN 

MANUFACTURING  COMPANY,  INC. 


177 


.  .  .  5:00  am  on  Sunday  morning.  I 
think  it  was.  Well,  shucks,  that's 
better  than  not  being  able  to  speak 
. , ,  right?  I  wasn't  all  that  interesting, 
but  if  you  would  like  to  hear  me  you 
can  get  a  tape  of  the  debacle  from  73 
for  S4.  An  hour,  about. 

One  exhibitor  made  the  mistake  of 
parking  his  van  on  a  Boston  street  and 
had  the  roof  almost  pulled  out,  along 
with  the  CB  and  ham  rigs  attached  to 
it 


The  most  popular  exhibits,  again, 
were  the  computer-oriented  ones  by 
The  Computer  Store,  Computer  Mart, 
and  American  Used  Computers.  I'd 
sure  like  to  see  more  combination 
hamfests/tomputerfests  .  , .  perhaps 
with  the  hamfest  pan  centered  on 
Saturday  and  the  camp uterf est  on 
Sunday  , . .  I  think  it  would  be  good 
for  both  groups  ...  as  well  as  the 
about  33%  overlap  between  them, 

One  week  after  the  New  England 


ARRL  convention  came  Expo  76  at 
Chicago,  This  affair  is  improving  every 
year.  There  is  talk  of  moving  it  to  a 
hotel  near  O'Hare  next  year.  Expo 
had  me  on  the  program  ,  , ,  in  prime 
time,  by  golly.  I  didn't  have  that 
much  different  to  say  from  Boston,  so 
there's  no  good  reason  to  make  tapes 
available  of  this.  I  talked  a  lot  about 
Kilobyte t  as  a  matter  of  fact  -  . .  and 
we  took  a  lot  of  Kilobyte  subscrip- 
tions at  our  booth.  I  guess  just  about 


METER 
CRYSTALS 

FREQUENCIES 
IN  STOCK 


FOR  THESE 
RADIOS 


CleggHT-146 
Drake  TR-22 
Drake  TR-33  rec  only 
Drake  TR-72 
Genave 


Heathkit  HW-202I 
rec  only 
Heathkit  HW-202 
Icom/VHF  Eng 
Ken/Wilson 
Lafayette  HA-146 
Midland  13-505 
Regency  HR-2 
Regency  HR-212 
Regency  HR-2B 


Regency  HR-312 
Regency  HR-2MS 
S.B.E. 

Sonar  1802*3-4,  3601 
Standard  146/826 
Standard  Horizon 
Swan  FM  2X 
Tempo  FMH 
Trio/Kenwood  TR2200 
Trio/Kenwood  TR7200 


146. 01T 

6.61B 

6.04T 

6.64R 

6.07T 

6,67  R 

6.10T 

6.70R 

6.1  1ST 

6.715R 

6.1  3T 

6.73R 

6.145T 

6.745R 

6.616T 

6T76R 

6.175T 

6.775R 

6, 1ST 

6.79R 

6.22T 
6,82R 
6.25T 

6.85R 
6.28T 
6,88R 
6.31  T 
6.91R 
6.34T 
6,94R 
6.37T 
6.97R 
6.40T 
6,46T 
6.46R 
6.52T 
6.52R 
6.55T 
6.55R 
6.58T 
6.5SR 
6.94T 
7.60T 
7.00R 
7.63T 
7.03R 
7.66T 
7.06R 
7,69T 
7.09R 
7.7  2T 
7J2R 
7475T 
7.15R 
7.78T 
7.18R 
7.81T 
7.21  R 
7.S4T 
7.24R 

7.87T 
7.27R 
7.90T 

7.30R 
7.93T 
7.33R 
7.9  6T 
7.36R 
7.99T 
7H39R 


Not*     If   you  do  not   know   type   of  radio,  or 
frequency,    formula  and  loading  capacitance. 


if  your  radio  ii  not  titisd,  rjiw  fundamental 


CRYSTALS  FOR  THE  IC-230  SPLITS  IN  STOCK    13-851 1 11  MHi:  13.804444  MHi; 
UHt;  HEATHKIT  HW2Q21  &QQ  KHf .  OFFSET  11 .3  MM*;  S6.50  t*. 


13.917778 


MQDiL  Gfi  1 444  —  Uti^it  Two 
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Vrmr  *  hi  "■'■<*  d-c»f*  Mnmum 
rwomwtt  it  th»  hoiizDn!  Stiunt  'ed. 
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lurvivil:   LOO  WPH    imlilii  mi  vert. 
c*r   pips   up   in    IV    OD    SO  239 
Cm*  CDtiiHCter  S52-95 


BBLT- 144 


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SHIPPING 


We  c*n  ship  COD.  Unt  clasi  mail.  Orders  tan  be  patd  by    check,  money  order.  Matter  Charge. 
Or  BankAmericafd.  Order t  pfepakt  ar^  shipped  postage  paid.  Phone  orders  Accepted    Crystals 
art  guaranteed  for  lift.  Crystal  I  ar*  all  55-00  each  {Mass  r«*denis  add  25rf  um  pet  crytfalf 
U.S.  f  UNDS  ONLY 


WB  stutter  to  o***G£  OTTxx/r  nottqe 


So*  469 
Depi.  9?6 
Qutncy.  MA  07169 
161 7,47 1.6427 

Store  Hours 
Daily  9-9 
Sal   &£ 


We  are  authorized 
(imributors  lor 
Icom  and  Standard 
Commij  n  ical  ion* 
E^rprneni.  C3  meter! 


everyone  is  getting  73  by  now. 

While  I  enjoy  getting  out  and  saying 
hello  to  a  thousand  or  so  readers,  I 
wonder  whether  Tm  doing  better  that 
way  than  staying  at  home  and 
answering  the  mail  ,  ,  ,  and  there  is  an 
awful  lot  piling  up  as  a  result  of  my 
traveling  around.  I  dunno, 

SUPPORTING  CAST:  II 
A$    promised,    here  is  the  second 
installment  of  portraits  from  the  73 
gallery. 


Chris  Di/fon  ts  seen  hew  working  op 
fife  records  of  orders  for  books,  tapes, 
and  hack  issues  seal  out.  Every  now 
and  then  something  gets  screwed  up  in 
shipment  and  she  has  to  be  able  to  go 
back  and  find  what  was  shipped  where 
&nd  when. 


Noet  Ray  Seff  is  working  on  negatives 
for  73  Magazine  and  for  the  latest  73 
books.  Photographs  have  to  be  made 
separate fy  and  glued  onto  the  negative 
of  the  type  and  drawings  ...  a  job 
requiring  great  precision,  Negatives  are 
never  perfect,  so  Ray  has  to  find  all 
pin  holes  and  go  over  them  with  paint 
to  opaque  them.  Where  ads  are  placed 
on  pages,  negatives  have  to  be  spiked 
together,  Duplicates  are  then  made  on 
single  sheets  of  fUm.  Ray  does  the 

splicing also    adding    the    page 

numbers  at  the  bottom . .  .  ere 

Continued  on  page  208 


178 


STATEMENT  OF  OWNERSHIP, 
MANAGEMENT  AND  CIRCULATION 
(Require  by  33  U-S.C-  3685k  1.  TUk  Of 
publication,  73  M^g^aine.  1.  DnilE  of  filing, 
15  Sept  1976.  3.  Frequency  of  issue. 
Monthly.     A.     Ho      of     issuer    pubNsh-ed 

annually,   12.    B.    Annual  subscription  price. 

Si  0.00.  4.  Location  of  known  office  of 
publication  (Srreet,  City,  Caunty,  State  ancf 
Z"fP  Codel  fNoi  printers],  Pino  Street, 
Peterborough,  Hi!  J  sboro  County,  N,H. 
03458.  5.  Location  of  the  h£adquar  Was  or 
general  bu&tness  offices  o"f  the  puhrishm-s 
jNot  printers),  Fine  Street,  P&iarbora-urjh,. 
Hjtlsboro  County,  N-.H.  0345S.  6  tomes 
and  complete  addresses  of  publisher,  ediioi, 
and  managing  editor.  PutjlisheF  (Name  and 
Address}  Wayne  Green,  Pet  e-i  borough.  ftf.B. 
03458.  Editor  (Name  and  Address)  Wayne 
Green,  PetarborotJ-gfhr  N.H,  0345S,  Manaaing 
Edftpt  (Nan™  jmd  Address  t  J^gk  Burnett, 
Pflter borough,  N.H.  0345B.  7.  Owner  ilf 
nwned  by  3  corporation,  its  nam?  and 
address  must  be  stated  and  eiso  immediately 
1 1 ka rounder  the  names  and  addresses  of 
stockholders  owning  or  holding  1  percent  or 
more  of  total  amount  of  stock.  If  not 
owned  by  a  corporation,  the  names  and 
addresses;  a  I  the  individual  owners  must  be 
given.  It  owned  by  a  partnership  or  other 
unmoor po rated  firm,  its  naniu  and  address, 
is  weH  as  that  of  each  individual  must  be 
given.}  fstarne,  73  Inc..  Peterborough,  N.H. 
03458.  Wayne  Green,  Peterborough,  N.H. 
034&8.  B.  Known  bondholders,  mortgage  k. 
and  other  security  holders  owning  or 
hold i rig  t  percent  or  more  at  total  amount 
of  bonds,  mortgages  or  other  securities  flf 
there  are  none,  so  stute)  Name,  none.  9.  Foi 
completion  by  nonprofit  organisations 
authorized  to  mail  at  special  rates  (Section 
132  122,  PSMf  Thte  purpose,  function,  and 
nonprofit  status  of  this  organization  and  the 
exempt  status  lor  Federal  inconiu  tax 
purposes  iCheck  un«)  N01  applicable,  10. 
Extent  end  nature-  of  circuSation.  00 
Average  No,  copies  each  issue  during 
preceding  12  months.  fY)  Actual  No.  copies 
oE  singli!  issue  published  nearest  to  filing 
date.  A,  Total  No,  copies  pri  it  ted  TNot  Press 
RunS  (X)  96,584  (Y)  98.492.  &.  Paid 
circulation  1,  Safe*  through  deaiers  and 
carriers,  street  vendors  and  counter  sates. 
ROiMu  2.  Mail  subscriptions  (Xr  &Or72l  (VI 
92,514.  C,  Total  paid  circulation  (Sum  of 
10B1  and  10B2)  iX\  90,721  <Y1  92,514.  O. 
Free  distribution  by  mail,  carrier  ot  other 
means  samples,  com p lime ntaryt  and  other 
free  copies  (X}  1,630  1Y1  1,713.  E.  Total 
distribution  (Sum  of  C  end  D|  (X}  9yr40l 
(Y|  94,227.  F,  Copies  not  distributed  1. 
Office  use,  left  over,  unaccounted,  spoiled 
after  priming  {Xf  3,806  (V)  3,381.  2. 
Returns  from  news  agents  (X)  377  (Y)  284. 
S  Total  iSum  nf  E,  F1  and  2  -  should 
equal  net  press  run  shown  in  A r  (X]  95,584 
|Y|  98,492,  It.  I  certify  that  the  statements 
made  by  me  above  are  corheci  and 
complete.  Signgturfi  and  title  oF  editor, 
publisher,  business  manager r  or  owner  BiH 
Mahonuy,  Business  Manager, 


NOTICE 

NEW  TOLL  FREE  PHONE 
NUMBER  FOR  ORDERING 
SUBSCRIPTIONS,  BOOKS 
AND    TAPES    FROM    73    - 

800-2585473 

DR 
800  251-6771 

7$  magazine 

pLrterborotigii  KH   034  5B 


Tracking 

the  Hamburg lar 


STOLEN:  Drake  TR-22  2  meter  trans- 
ceiver, s/n  640139,  beige  TrimlineTT 
Handset,  magnet  mount  quarter  wave 
antennae.   Crvstats  for  52/52,   16/76, 


37/97,  B7/27,  63/03,  34/94.  Stolen 
from  Rick  Simpson  K0UZP,  2723 
Rigel  Drive,  Colorado  Springs  CO 
80906,303  471-2059, 


TAKEN:  Wilson  T1402  S/M  2  meter 
handie-talkie,  s/n  OR 6427.  Crystals 
for  52/52,  22/82,  25/85,  16/76, 
34/94,  69/09.  Stolen  from  James 
Nettle,  PSC  ffl,  PO  Box  2493, 
Peterson  AFB  CO  80914, 

RIFLED:  Heathkit  HW  202  with 
installed  Tone  Burst  Encoder, 
TTPAD,  six  (6)  sets  xtals  34/94, 
94/  ,  25/85,  115/715,  28/88,  1 6/76 
(switch  indicates  04/64  but  xtafs  are 


KEN  SCO  COMMUNICATIONS  OFFERS 
ICOM's  FIRST  FM  FOR  TABLE! 


ICOM 


Now  ICOM  Introduces  1 5  Channels  of  FM  to  Go! 

The  New  IC-215:  the  FM  Grabber 


It  puts  good  times  on  the  go.  Change  vehicles, ..walk  through  the  park,,, 
climb  a  hilL.and  ICOM  quality  FM  communications  go  right  along  with 
yoiLLong  lasting  internal  batteries  make  portable  FM  really  portable. 

Multiple  accessory  features  make  conversion  to  external  power  and  antenna  fast 

and  easy. 


+  Front  mounted  controls 
and  top  mounted  antenna 

+  Narrow  filter   (15KMz 
compatible  spacing) 

+  15  Channels  {12  on  dial 
3  priority) 

+  Fully  collapsible  antenna 

+  Compatible  mount  feature  for 
flexible  antenna 

+  Dual  power  (3  watts  high 
400  mw  low,  nominal) 

+  External  power  and 
antenna  easily  accessible 

+  Lighted  dial  and  meter 


Kensco  Communications  includes:  5  popular  channels. 
Also  handheld  mike  with  protective  case,  shoulder 
strap,  connectors  for  external  power  and  speaker,  9 
long-life  C  batteries. 

GRAB  THE  NEWIC-215FM  PORTABLE 


We  ship  COD  first 
class  mail.  Prepaid 
orders  are  postpaid 
by  us.  Use  check, 
money  order.  BAC 
or  MCin  U.S.  funds. 


Box  469 
Dept.  976 
Quincy,  MA  02169 
(617)471-6427 

Store  Hours: 
Daily  9-9 
Sat.  9-6 


We  ets  authorized 
distributors  for: 
Icom  and  Standard 
Communications 
Equipment,  (2  meter} 


mj^i  r  Fjrje 


PRiCES  SUBJECT  TO  CHANGE  UDTHQUl  iVU-ntf 


179 


16/76}.  My  ssn  125-32  5960  on 
various  parts  internally  including 
underside  of  trans  and  rec  boards. 
Also  stolen:  Courier  Comet  23  CB,  s/rt 
12300643.  Stolen  from  my  parked 
auto  in  Garden  City  NY  on  August 
30,  1976.  If  found,  please  contact 
heart  broken  owner,  Daniel  KL  Gordon 
WB2YUJ.  155  Nimbus  Road,  Hol- 
brook,  NY  11741. 

ROBBED:    Yaesu    FR1015D1G    HF 


digital  receiver,  s/n  6C31339,  Yaesu 
FL101  HF  digital  transmitter,  s/n 
GE 3062  76.  Stolen  from  Associated 
Electronic  Service,  404  Arrawarta, 
Colorado  Springs  CO  80909. 

RIPPED  OFF:  Kyokuto  FM-144  2m 
transceiver,  s/n  6215.  Stolen  from 
vehicle  at  Los  Angeles  Coliseum  on 
July  24,  1976.  Contact  Abel  J.  Tapia 
WA6FSZ,  PO  Box  41 4r  Montclair  CA 
91763, 


RUSTLED:  Drake  MN-2000  matching 
network,  s/n  6485.  Heath  SB -6 50 
frequency  counter.  Stolen  on  August 
29r  1976  from  auto  in  Rockland 
County.  Please  contact  Cliff  Cooley, 
Jr.  WN2GHL,  4  Camp  Hill  Road, 
Pomona  NY  10970. 


HIJACKED:  Icorn  230  2  meter  radio, 
s/n  240-2915,  forcibly  removed  from 
vehicle  in  Fort  Wayne,  Indiana  on 
September  4,  1976,  Report  filed  with 
Fort  Wayne  police.  Kenneth  C. 
DeGroff  WB90CW,  62322  Oak  Road, 
South  Bend,  Indiana  46614 


FCC 


swmom 


ANNUAL  CHRISTMAS 

PARTS  SALS! 

All  parts  are  BRAND  NEW  PRIME  UNITS  unless  otherwise  specified.  Some  are 
limited  in  quantity  and  these  prices  are  effective  only  until  December  24 ,  1976. 


PC  BOARD  STOCK 

First  grade  epoxy  glass  I/L6'h  cut  to 
your  size  for  only  $0.02  per  square  inch, 
single  aided.  Double  sided  $0,035  per 
square  inch. 

# 

PC  BOARD  PROJECT  KIT 

This  kit  includes  an  assortment  of  single 
and  dgtibie  sided  PC  stock  in  useahle 
sizes,  plus  one  pint  of  immersion  tin 
plate  solution  and  five  pounds  of  etch. 
Instr.  included.  $14.95  ea, 

IMMERSION  TIN  PLATE  SOLUTION 
For  professional  PC  boards  you  must  tin 
plate  them.  Enhances  severability  and 
appearance.   1  qt.  will  plate  dozens  of 
average  size  PC  boards.  Ho  few,  no  muss 

UART 


-  dunk  "em  and  out  come  bright  shiny 
easy  to  solder  PC  boards.  Instr.  incl. 
$8. 95/qt. 

COPPER  ETCH  CRYSTALS 
Dry  powder  mixed  with  water  forms  a 
very  fast  and  safe  copper  etch  solution. 
Easy  to  dispose  of  when  exhausted. 
Enough  to  make  three  gallons  of  etch,  5 
lbs,  $4.95  ea. 


V1ATRON  SYSTEM  21 
(BRAND  NEW  UNITS) 

Checked  out  and  operable,  but  sold 
as- is.  Only  3  left  so  act  fast.  Shipped 
freight  collect  for  ONLY  $295,00 
(Check  previous  ads  of  our  competitors 

and  be  AMAZED) 


MULTI  VOLTAGE  REGULATOR  CARD 
Removed     from     functioning     power 
supplies  and  guaranteed.  Complete  regu- 
lator for  +15,    15  and  +5  volts.  Currents 
in  excess  of  3.0  Amps.  You  supply  the 
raw  dc  voltages  and  a  case;  we  supply 
the  rest,  including  the  pass  transistors 
good    for    10.0   Amps.    Schematic   in- 
cluded. $14.95 
# 
VIDEO  MONITOR 

(BRAND  NEW  &  GUARANTEED) 

9d'  diag  CRT.  In  cabinet  with  ac  power 

supply.  Accepts  composite  video  signa] 
and  features  adjustable  scan  rates.  117  V 
ac.  AU  solid  state.  $99.95 

# 

ROMS 

KR 2376-30  Keyboard  encoder  -  $6.95 

{Data  and  code  sheets  inol.) 


COM2502/2017  40  pin  DIP  UNTESTED*  S3. 95. 
checked  work  fine  at  4.5  volts  instead  of  5.0. 


But  the  ones  we've 


* 

LINEAR 

709  Op  Amp 

TO-& 

$  .20 

301AN 

DIP 

.49 

DATEL  IC6B  DAC 

9.95 

LM309K 

T03 

1.49 

NE555 

DIP 

,50 

LM5000  5A 

Reg 

4.95 

TRANSISTORS 
2N3859Equiv-  NPN 
TIS93  PNP 

TIS98  NPN 

MPS2222A         NPH 
MPS29Q7A         PNF 


$ 


.20 
.49 
.59 
.20 

.20 


* 

IC  SOCKETS 
(SOLDER  PIN) 

Spin  %  .20 

L4  pin  .25 

16  pin  .29 

24  pin  .49 

40  pin  .99 


We  also  stock  an  in-depth  line  of  7400  series  TTL,  including  CMOS.  Please  inquire  as  to  availability 
and  price.  Video  Display  Terminal  subassemblies  and  Keyboards  are  stitl  available,  but  the  supply  is 
dwindling.  Graphics  Drivers  are  in  full  production  and  available  from  stock.  Please  see  our  ads  in 
August  and  September  73  for  details, 

TERMS:  Fun  cash  price,  plus  shipping  costs  MUST  be  included  with  order.  We  accept 
Master  Charge  and  BankAmer  icard,  Please,  NO  CO  Ds.  Excess  shipping  payments  refunded 
promptly.  Prices  and  availabilities  subject  to  change  without  notice. 


suimiwu;*™,™ 


y 


360  Merrimack  St.,    Lawrence  MA  01343  Hours:  8:00AM  to  5.00PM 
(61 7 }  688-0751 


FCC  ANNOUNCES  CHANGE  IN 
ISSUANCE  OF  NOVICE  CLASS 
AMATEUR  RADIO  CALLSIGNS 

As  part  of  its  continuing  effort  to 
provide  the  public  with  rapid  and 
effective  service,  the  Commission  will 
shortly  cease  issuing  distinctive  call- 
signs  to  Novice  class  amateur  radio 
stations. 

Presently,  Novice  class  stations  in 
the  continental  United  States  are 
issued  callsigns  prefixed  by  the  letters 
"WN"  to  facilitate  their  identification 
as  Novice  stations.  Novice  stations 
outside  the  continental  United  States 
are  also  assigned  distinctive  callsigns. 
This  practice  has  proved  to  be  unsatis- 
factory, however.  It  has  caused  several 
difficulties  in  the  processing  of  ama- 
teur applications,  not  the  least  of 
which  are  the  issuance  of  the  same 
callsign  to  two  different  stations  and 
the  issuance  of  callsigns  in  callsign 
blocks,  such  as  "WC,"  which  are  not 
available  for  general  amateur  use. 

Accordingly,  beginning  October  1, 
1 976,  each  Novice  callsign  was 
assigned  in  accordance  with  the  fol- 
lowing; 


Present  Prefix 

New  Prefix 

WN0 

WB0* 

WN1 

WB1 

WN2 

WD2 

WN3 

WB3 

WN4 

WD4 

WNS 

WB5* 

WN6 

WD6 

WN7 

WB7 

WN8 

WD8 

WN9 

WB9* 

WH6 

KH6 

WL7 

KL7 

WP4 

KP4 

WP6 

KP6 

WG6 

KG6 

WS4 

KS4 

WS6 

KS6 

WV4 

KV4 

WW6 

KW6 

WJG 

KJ6 

*  Callsigns  in  these  areas  are  presently 
nearing  the  end  of  the  WB  series. 
After  "WB'J  prefixes  are  depleted, 
"WD'J  callsigns  will  be  issued. 

All  amateur  Novices  with  license 
expiration  dates  of  October  1,  1976 
or  later  will  be  issued  new  Novice 
licenses  in  the  near  future,  Such  new 
licenses  will  be  identical  to  the 
licenses  superseded,  except  that  they 
will  have  printed  on  them  the  callsigns 
the  Novice  licensees  would  have  been 
assigned  under  the  old  callsign  assign 
ment  system  upon  obtaining  higher 
class  operating  privileges,  The  new 
callsign  must  be  used  by  the  Novice 
licensee  as  bis  callsign. 


180 


INTRODUCES  THE 

VERSATILE 

NEW 


©  1976 


More  Channels... at  the  flip  of  a  switch 

Unlock  the  unique  mode  switch  and  12  channels 
become  144 

More  Sensitivity,  Less  Interference 

.25  juV  Sensitivity  plus  75  db  adjacent  channel 
selectivity  and  70  db  image  rejection 

More  Power  Out 

35  watts  nominal  with  a  minimum  of  30  watts 
across  the  band 

. .  .for  a  lot  less 

$26900 


^€^T-€^\CU    ELECTRONICS.  INC. 


Amateur  Net 

7707  Records  Street 
Indianapolis,  Indiana  46226 


THE  FM  LEADER 


2  METER 


6  METER  9C 


220  MHZ 
440  MHz 


*&> 


**%£: 


you  can. 

The  ETK  (Electronic  Touch  Keyer) 
processes  inputs  and  sends  perfect 
dots,  dashes,  and  spaces  at  speeds  of  7 
to  55  wpnrL  The  LED  indicators  dis- 
playing dots,  dashes,  and  spaces  serve 
as  a  visual  training  aid  for  the  less 
proficient  CW  operator,  17  ICs,  relay 
output,  side  tone  speaker*  120  VAC. 
Inquiries  invited. 

for  only  145.00 

(includes  instruction  book] 

Order  direct  from: 

RO,  Box  1125 
S=  Kent,  Washington  98031 

Instruction  Book  1.00 


LOGIC  PROBE  KIT 


$14.95 


(plus  shipping) 

Now!  A  Digital  logic  Probe  kit  at  a  realistic 
price.  Red,  Green,  and  Yeflow  light  emitting 
diodes  signal  the  presence  of  logic  levels 
encountered  in  digital  circuitry,  Utilization 
of  transistor  and  integrated  circuit  switching 
techniques  permit  the  DIGAPEAKE-A  to 
indicate  logic  1.  logic  0,  and  pulsing  circuit 
conditions.  Complete  kit  including  easy 
instructions  is  available  now  from  .  . . 

Chesapeake  Digital  Devices  Inc. 

P.O.  BOX  341 
Havre  de  Grace.  Md.  21078 


WYOMING  RANCH  LAND 
Antelope,  deer,  elk,  wild 
horses.  Your  "Antenna 
Ranch/'  20  miles  North- 
west of  Rawtins,  10  acres  — 
$30  down,  $30  a  month. 
Will  trade  equity  for  ham 
gear,  test  equipment,  etc. 

FREE  info  —  maps  —  photos 

FOR  SALE  by  owner  — 
Dr,  Michael  K.  Gauthier  K6ICS 
9550E  Gallatin  Road 
Downey  CA  90240 


181 


-ECONOMY  LINE  — 

The  Greatest  Dollar 
Value  in  FM  Transceivers  I 


FM-76 


10  Watts 
for  220  MH/ 


"  '  M 


NOW  ONLY  $165.00 

including  223.50 

crystals 


CRYSTALS  IN  STOCK  FOR  ALL  POPULAR  CHANNELS 


WIA  RK-  3 


V 


15  Watts 
for  146  MHz 


NOW  ONLY  $169.50 
including  146.52  crystals 

•  Both  of  these  units  provide  1 2  Channels  with  individual 
trimmers  for  Receiver  and  Transmitter  Channel  Netting 

•  Both  have  a  big  clear  S  Meter/RF  Output  Meter 

•  Superb  Receiver  Sensitivity  and  Selectivity 

•  Crisp,  Clear  Audio  on  Transmit  and  Receive 

Sold  only  by  C^ 

Order  direct  toll  free  today . 

MASTERCHARGE  &  BANKAMERICA  CARDS  WELCOME 

(Please  .idd  2%  on  credit  card  putcnases, 

we  Day  sh (oping  on  orders  accompanied  by  check  or  money  order,} 


Ck9f!-» 


mmunicititm  Ctrp, 


208  CenterviHe  Road,  Lancaster,  PA  17603 

Toll  free  sales  &  services  -  Phone  (800)  233-0250 

In  Pa.  call  1717)  299^7221  [collect) 


This  Month's  Specials 

NEW 

Fairchild  VHF  Prescaler  Chips 

Type 

Description 

Price 

11C01FC 

High  Speed  Dual  5-4  Input 

0P/N0R 
S1MQ 

11C05DC 

1  GHZ  Counter  Dwde  By  4 

574.35 

11  CO  5  DM 

1  GHZ  Counter  Divide  By  4 

$11050 

11G06OC 

UHF     Prescaler    750     MHi 

0     Type 

Flip/Flop 

$1130 

11C24DC 

Dial  TTL   VCM 

$2.60 

11C44DC 

Phase  Free.  Detector 

$2.60 

11CS8DC 

ECL  VCM 

$4,53 

11C7QDC 

600  MHz  Flip/Flop  With  Reset 

$1230 

11CS3DC 

1  GHZ  248/254  Prescaler 

$29  90 

11C90DC 

650  MWz  ECL/TTL  Prescaler 

SI  6.00 

11C90DM 

650  MHi  ECL/TTL  Prescaler 

$24.60 

11C91DC 

650  MHz  ECL/TTL  Ptescaler 

$1600 

11C91DM 

650  MHz  ECL/TTL  Prescaler 

$24.60 

95H90DC 

250  MH*  Prescaler 

$950 

95H90DM 

250  MHz  Prescaler 

$16.55 

95H910C 

250  MHz  Pmcaler 

$9.50 

95H91DM 

250  MHz  Prescaler 

$1630 

RF  TRANSISTORS 

New 

RCA  40290 

12 -5w,  Ft.  Typ.  500MHz  2  watts 

min.  at  p.  in  0.5  watts 

$2.48 

2N2857 

5185        2N608Q 

$545 

2N3375 

$7.00        2N6081 

$8,60 

2N3866 

$1.08        2N6082 

$11-25 

2N4072 

5150       2N60S3 

$12,95 

2W4427 

SI  .20        2N60B4 

$13.75 

2N5179 

S68        2M6166 

$85.00 

2N5589 

S4.6Q        MRF511 

$8.60 

2N5590 

$6.30        MMCM918 

$2,50 

2N5591 

$10,35        MMT2857 

$2,50 

2N5637 

$20.70 

TUB  ES 

IP21 

$19.95       6146B/8298A 

$550 

2E26 

$4.00       6360 

S5.50 

4X150C 

$1800        6661 

lil.00 

4X150A 

$15.00        6680 

1 11 .00 

4CX25QB 

$24.00        6681 

i 

tl.DQ 

4K250F 

$22.00        6939 

$5.50 

DX415 

$25.00        7984 

$3.95 

572B/T160L       $22,00        8072 

$32.00 

BllA 

57.95        B106 

$1,95 

B13 

$19.00        8156 

S3.95 

931A 

59.95        B950 

$550 

4652/8042 

S695        6LQ6 

S3, 95 

5894 

$32.00       72B9/2  C39 A  $4 . 5  O  ea . 

6146A 

$4.25 

JUST  ARRIVED!   These   radios   haw   Just   been 

pulled  out  of  service,  Set  up  far  appro*,  150  MHz. 

Clean.   All 

tubes  included.   No  accessories 

i.   Prices 

FOB    PhoentjL 

Motorola  U43  GGT 

549  95 

GE  TPL 

$99.95 

GE   MT-33 

$39.95 

NICAD   Batteries  AAM   1,25  volts 

49*  ea* 

GEL/CELL  #GC1215,  12  volts,  15  amp  fin  $19-95 

We    have   s 

ill    types    of   test   equlpfiwht. 

Call    or 

write   today! 

C 

lectroqicft 

2543   N.  32ND  STREET 

PHOENIX.  ARIZONA  85008 

PH,  602-957-0786 

182 


*»?o^ 


you  can. 

The  ETK  (Electronic  Touch  Keyer) 
processes  inputs  and  sends  perfect 
dots,  dashes,  and  spaces  at  speeds  of  7 
to  55  wpm.  The  LED  indicators  dis- 
playing dots,  dashes,  and  spaces  serve 
as  a  visual  training  aid  for  the  less 
proficient  CW  operator.  17  ICs,  relay 
output,  side  tone  speaker,  120  VAC. 
Inquiries  invited. 

for  only  145.00 

(Includes  instruction  book) 

Order  direct  from: 

P.O.  Box  1125 
S=  Kent,  Washington  98031 

Instruction  Book  1.00 


We're  Fighting 
Inflation 


No  Price  Rise 


for  76 


FOR  FREQUENCY  STABILITY 

Depend  on  JAN  Crystals  Our  large  stock  of  quarlz 
cry 5 til  materials  and  components  assures  Fast 
Delivery  from  us1 


CRYSTAL  SPECIALS 

Frequency  Standards 
t00  KHz  (HC  *M1) 
1000KHKHC    6'U) 


S4  5G 
.4.50 

S2  50 


Almost  aM  CB  sets.  Tfl  or  Rec 

fC B  Synthesiser  Crystal, or  request) 
Amateur  Band  m  FT243  .      ea    11  50 

.  .    4/S S00 
80  Meter  $3.00060- meter  not  avail.) 

F.or  i  st  class  mail,  add  20*  per  crystal  For  Airmail, 
add  25*  Send  check  or  money  order.  No  dealers 
please 


■ 


Ofr.ol 

Bob  Whan  *  Son  Eieetfoniet,  ine 
2400  Cryslat  Of., 
F^Myer*,FJa>  33*01 
AH  Phones:  <St3)  *3*2397 

S*mf  10r  for  n€w  catalog 


TO 
THE  TOP 
FAST! 


NOW  YOU  CAN  CHANGE, 
ADJUST  OR  JUST  PLAIN  WORK 
ON  YOUR  ANTENNA  AND 
NEVER  LEAVE  THE  GROUND! 

Rohn  manufactures  towers  that 
are  designed  and  engineered 
to  do  specific  jobs  and  that  is 
why  we  have  the  FOLD-OVER 
TOWER  ..  designed  for  the 
amateur.  When  you  need  to 
"get  at"  your  antenna  just  turn 
the  handle  and  there  it  is.  Rohn 
"fold-over"  towers  offer  unbeat- 
able safety.  These  towers  let 
you  work  completely  on  the 
ground  for  antenna  and  rotator 
installation  and  servicing.  This 
eliminates  the  hazard  of  climb- 
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So  use  the  tower  that  reduces 
the  risks  of  physical  danger 
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Like  other  Rohn  big  communi- 
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galvanized  after  fabrication  to 

provide  a  maintenance  free, 
long  lived  and  attractive  instal- 
lation. Rohn  towers  are  known 
and  used  throughout  the  world 
...for  almost  a  quarter  cen- 
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operation.  You'll  be  in  good 
company.  Why  not  check  with 
your  distributor  today? 


Unarco-Rohn 

Division  of  Unerco  Industries,  Inc. 
P.O.  Box  2000.  Peoria,  Illinois  6t601 


183 


linears 

K=TO-3;     T*TQ-220;  TK-TO-W 

30111, H  op  «np 50.30 

304H  neg  volt  reg  .0 
305H  poa  volt  reg.0.75 

307H  op  anp hO.35 

308K  op  amp.  ......  .LOO 

309H  +5V  reg. ....   1,00 

309K  +5V  reg 

3  lift  comparator, 
31 1H  comparator. 
316H  hi  S  op  amp 
318H  fast  op  asm 
320/-12T  rag. 
339D  quad  compar, 
340/+5K  reg. 
340/ +5"  reg 
340/+6T  reg 
/+BK  re& 
340/+6T  re£ 
340/+12T  reg 
340/+L5K  reg 
340/+15T  reg... 
34u/+lfiK  reg... 


3770  dual  ZV 

3801*  %U  amp  .  .  .....0 

380B  2  watt  amp  1 
38 ID  lo  noise  op.  1 
382D  to  noise  op.  - L 

531H  hi  slew  op 1. 

54QH  power  driver. . I. 

555K  timer  0 

5650  PLL 

566H  VCO .2. 

567H  tone  decoder,. 2, 
7230  150  n«  reg. .   Q, 

7238  150  ma  reg 0 

725K  cop  op  anp. . . .2. 

733H  video  amp I. 

74LH  op  amp 0, 

741H  op   amp.  .Q, 

747 D  dual    741. .....0, 

748H,H  op  amp, , . , . .0. 
1458   ae*    5558M 

1496D  bal  nod 1 

1556H.H  tap  op  amp. 1. 
1558  see  5558M 
1596  flee  U96D 
3026H  trans  array.  .  I, 
3065D  TV  Bound  , . , .0. 
3G36D  trans  array,, I, 
4131H.M  op  amp, . . ,  , 0, 
411615  quad  op  amp.  .1. 
4154D  track  reg. . . . I , 
4194TK.  pur  4L94D.  .  .2. 
■'- 1  '-3 5TK  +13V  reg.  ,  .  .?.. 
4250H  program  op. . . 1 , 
47  3  90  dual  op  amp. .1. 

4741H  dual   741 0, 

5556H  see   1556M 
5558K  dual   741  op, .0, 
803BD  func  gen 4, 


CMOS 

4000 , $0.25 

4001 0.25 

4O02 0.25 

4QQ6., 1.50 

4007 0.2S 

4008 

4009...  .0,45 

4010 ,0.45 

4011.  .0,25 

4012 .0   25 

4013.  0.50 

4014 ....,,.  1j  }Q 

4015 1 

4016 0,55 

4017 1.25 

4018 ,1.50 

4019 .0,55 

4020 1 ,  50 

4021.. 1.45 

4022.  1    20 

4023  025 

4024.  .0.55 

4025.  .0.25 

4026.  1.50 

4027  0,65 

4028  .1.00 
4029.            .1.35 

4030 0,45 

4033 1.50 

™  V  ^r  J  *        •  w   t  i»  w  *w  w  w   w  i"  w   ■■■  »  i^t^f 

4037 0.50 

4040 .  .  ,.  ,  ,1.50 

4042  .085 

4043.  .0,60 

4044  .0,60 

4047  :,50 

4049.  0,50 

4050  0.50 

4116.  0  60 


TTL 


7400 
7401 
32 
7403 
7404 

7405 
7406 
7407 
7403 
7409 
7410 
7411 
74  U 
7414 
7416 
7417 
7420 
7422 
7425 
7426 
7427 
7430 
7432 
■  37 
7438 
7439 
7440 
7441, . . 
7442 
7445. 
7446 . . . 
7447 
7448 
7450. 
7451 
7453 
7454.. . 
7460 

7461  •  -  • 
7472 
7471  -  -  - 
7474 

7475  - . . 

7476  -  .  - 
7483 

7485  -  -  - 

7486  . .  * 
7489 
7490 
7491 ■ -  - 
7492 
7493^ 
7495  ^ 
7496... 
74100  .* 
74107.. 
74121 
74123. . 
74125.  . 
74126, . 
74143 . - 
74145, ♦ 
74150.  . 
74151^ 
74153,. 
74154. 
74155- - 
74156-. 
74157 ^ 
74159.. 

160- 
74161 
74162 
74163- - 
74164 

;ii65^ 

74173 
74174 
74175- 
74176- 

74177. 

74179. 
74180. 
74181 
74182- 
74190 
74191 
74192 
74193 
74194. 
74195 
96 
74197 

74199- 

74273. 

74365. 

74366 

74367. 

7436S. 

74390 

74393. 


>  ■ 


F   ■   F  * 


¥■      W      ■  ¥     f-  + 


0.36 

0.89 
1.60 
0.36 
2,23 

.0.  SO 

Q.9S 

0.98 

0.71 

0.98 

0.98 

1.34 

0.36 

0,45 

0.71 

0.71 

0.71 

5  .  00 

,0.  89 

.1.07 

.0.71 

.0,  B0 

1,25 

.0.71 

0.90 

0.71 

-1.50 

0.39 

,0.89 

0,89 

.0.89 

.1.34 

.1.34 

-1.34 

■  1 .  52 

1.34 

0.98 

.0.98 

.0.75 

0.98 

2.23 

.0.30 

.1.34 

1.34 


Q.98 
1.96 
1.96 
1.89 
G.6J 
0.63 
0.63 
0.63 
.  1 .  50 
■  1.50 


8000  series  TTL,  micro- 
processors. &  our  chip 
sets  are  listed  in  our 
flyer . 


low  power 
schottky 


74LS00 -  - 
74LS01 
74LS02 • - 
74LSD4 . . 

74LS0S- ■ 

1.S10 
74LS11 
74LS20 ■ - 
74LS21 
74LS22 . 
74LS27., 

74LS30 . . 

74XS32  - 

74LS37.- 

741^38 .-..»►» 

74LS42 . . 

" -LS74 . . 

74LS75, , 

74LS109. 

74LS124. 

74LS125- 

74LS126. 

74LS132 

74LS138- 

74LS139 . 

74LS155 

74LS157. 

74LS160- 

74LS161- 

74LS162- 

74LSI63^ 

74LS168- 

74LS169. 

74LS174. 

741^175 

74LS221- 

74LS240 ■ • 

74LS257 

74LS258 

74LS273 

741,5283-  ,  ,  .  .  . 

74LS367 

74LS368 

74LS377 

74LS378- 

TRANSISTORS 
2H2221  NPN.. . 
2N2222  $m..„ 
2N2907A  PNPt. 
2N3055  NPN. . . 
2H3904  NPN... 
2N3906  PNP, ,, 
2N4249  PKP.. . 
2N4250  PNP. . . 
2H4400  NPN . . . 
2N5135  NPN, . . 
D41D1  PNP  pwr 


..$0,36 

...0.36 

0.36 

0.42 

0.36 

0.38 

...  0 . 36 

...0,38 

..0.38 

. .0.38 

-.0,36 

. .0.38 

-0.53 

,0.53 

..1.25 

.0.56 

..0,85 

.  0 ,  60 

.2.50 

..0,75 

0.75 

..1.50 

.,138 

,.1.38 

.1.38 

-,  i.25 

85 

35 

.  .1.85 

i .  as 

.,1,87 

..1.87 

1.38 

,1.35 

..i.38 


.1,20 

. . 1 . 00 

.  . 1 , 00 

L .  88 

1,38 


.7/51.00 
-5/S1.00 
-5/$1.00 
^.?0.7S 
.7/31.00 
.6/51,00 

.5/51,00 

-5/$1.00 
.5/jl,00 

10/11,00 
$1.50/pr 


FIELD  EFFECT  TYPES 

Dual   N  UHF/VHF. .3/91,00 

Heh.  RF  amp 3/31,00 

Dual  N  Id  noiae . 2/ SI . 00 
N  ch.  gen  purp, ,4/Sl, 00 
6AK5  plug-In ,31.00 

MEMORY  ICs 

2102L1 ,  not  the  average 
2102,  450  tis  guaranteed 
and  low  power , , . , , $1 . 95 

2112  4*  256  RAM.  ..$2,95 

5202  2K  EROM $9.95 

5203  2K  EROM §9.95 

5204  4K  EROM $17.50 

5600  8*32  PROM.  ..§2,50 
5610  open  collec  . $2  95 
7489  64  bit  RAH, . ,52.23 
74206  156  bit  RAM,  $5,90 
74S471  Fast  8*256  ROM 
in  DIP  package ..,.$9.50 
93410  Bipolar  256  bit 
RAM;    fast ....$2,00 


MDUCTORS   all 

microh£iiriea 

X.O 


■        ■       •       •        -      -      r      ■      ■      ■ 
......  .       .       .       . 

------rBBBB 

*      ■     ■     .     ¥      ■ 

+     **■•+■      +      »      ■      -       r      ■ 

w    w    ■.     r     w      r     -w      w      r     v 


values   In 


10/51,00 
LO/SI.OO 
10/81.00 

10/ si. 00 
10/ $1. 00 
10/5100 
10/ $1.00 
10/51.00 
10/$1.00 
10/51.00 
10/51.00 
10/ $1.00 
10/51. 00 
10/ $1.00 
10/51.OO 
10/51.00 
10/ $1.00 
10/51.00 
10/51.00 

lom.oo 


bill  codbout  electronics 
box  2355,  Oakland  airport,  ca  946m 


capacitors 

All      C*p*vitOTf      lo     uF 

except  when  noted. 


TAKTALUMS 
.47§35V 
.  82  I  20V 
2.2  #  20V.. 
2.7  @  20V.. 
3   3  3   IW.  . 
4.7  f  10V.. 
22  ^  10V. , . 
33  §  10V. . . 
39  I  10V. . . 
47  9  6V 


4/S1.0O 
4/ SI   00 

4/$1.00 

4/ $1.00 
-/SI. 00 
4/S1.00 

3/51.00 

.  .  .  .  *  i  f  •}  L  .  [Hi 

3/51.00 

3/51.00 


CLECTROLTT1CS 
10?  10VVFC  typ« 
10  9  250V.   sxial 
12^  250V.  axial 
lOOflOV.    txUl 
100  9  35V.    PC.,., 
100$  50V,    FC... 

220  §  25V,    PC 

250  |  25V.    PC-  . 
500  |  15V. ... 

1000 #  25V. 

2000|  30VT   PC. 

4000 1  20V. 

10000  §  10V 

MYLARS 

.0039.    50V , 

.005,    25V 

*0064.    50V. 

.01.    50V 

.02,   50V, 

.033,   50V. 

047,   50V 

.068.   50V 

.1.    50V 

.22,    50V 

5.0,    100V,    107.. 
10.    100V,    10%,. 


5/$l,00 
3/51.00 
3/51.00 
5/51.00 
4/51.00 
4/51.00 
4/51.00 
4/51.00 
3/51.00 
5/51.95 
1/50.95 
1/S0.9S 
1/5125 


10/51.00 
10/5100 
10/5100 
10/51.00 
10/51.00 
10/S1-00 
10/51.00 
10/51.00 
10/51.00 
10/51  00 
.2/51.50 
1/S1.50 


DISC  CERAMICS 

10  pF 10/SO  ,45 

220  pF 10/$0  +  45 

,001 10/S0.50 

.0027 10/50  50 


p  r    i  ■ 


.005 
01 

■  V  £  r   *   m   *   *    k    ■  i 

,05 

,.  1.  .  .  +  .  * 


I    ,    I    L 


. , .10/50.50 
...10/£0+50 
...10/S0, 75 

...10/31,00 
. . .10/$!, 25 


HIGH  VOLT  ELECTROLTTTICS 
150@350V.,..#t, 2/$1.35 

200  @  175V 2/51.35 

10  d  400V  with   4  @  350V  & 
100  <?  350 ,,2/$1.20 

POLYSTYRENES 

150  pF 

180  pF. 

220  pF. 

270  pF. .*.... 
330  pF, *...., 

390  pF 

470  pF 

560  pF 

680  pF  . 
820  pF. . 
910  pF... 
1000  pF. . 
1200  pF.. 
1500  pF  , 
1800  pF  . 
2000  pF.. 
2200  pF  , 
3300  pF, , 
3900  pF . . 


■  *  ■  «  ii 


..10/51,00 

. .10/$1,00 

10/51.00 

. .10/51,00 

. .io/$i.od 

, 10/51,00 
.  .10/51.00 

. .I0/$i.oo 

-10/51.00 
,.10/$1.00 
, . 10/51.00 
..10/51,00 
.10/51,00 
,,10/|1,00 

.10/ $1,00 

10/51.00 

. .10/51.00 

. .10/ $1.00 

..10/51.00 


TR1MPOTS 
sount  j   ^ 
250  olm  j 
500  ohms , 

ue 

Z.5K. 

- 

101E 

50K 

UL 


■  -  - 


single  turn  PC 

watt. 

. . . .5/51,00 
5/51,00 
5/51.00 
3/51. 00 

5/51.00 

....... 5/51  *  00 

5/51.00 

5/51,00 


C1H6000  op to  -  isolator 
LED  /  photoresistor   in  a 
tiny  package $3.50 

RESISTTJR  ASSORTMENT  #1: 
500  k  watt  resistors 
with  good  nix  of  values 
$3-95 


resistors 


**QUARTER  HATTT  10X  (aone  5X) 


100  OF 

ANY  ( 

>HE  VALUE 

51. 70 

1000  OF  AffY 

ONE  VALUE. 

.    $15.30 

Choose 

frofc! 

the  following 

{Sm  ohms) 

1*0 

27 

470 

8.2K 

150K 

1.2 

30 

510 

9.  IK 

I60K 

1.5 

33 

560 

im 

180K 

1,8 

36 

620 

UK 

200K 

2.2 

I* 

680 

UK 

220K 

2.4 

43 

750 

15K 

240K 

2.7 

47 

820 

15K 

270K 

3.0 

51 

910 

lfeic 

300K 

3.3 

56 

IK 

18k 

330K 

3-6 

62 

1.11 

20K 

360K 

3.9 

68 

1.2K 

22K 

390R 

4.3 

. 

1.3K 

24K 

430K 

4.7 

62 

1.5K 

27K 

470K 

5-1 

91 

1.61 

30K 

510K 

5.6 

10O 

l.SK 

33K 

560K 

6-2 

110 

2. OK 

36K 

620K 

6.8 

120 

2.2£ 

39K 

680K 

7.5 

130 

2.4X 

43K 

7501 

8.2 

150 

2.7E 

47K 

820E 

9.1 

160 

3. OK 

5 IX 

910K 

10 

ISO 

1.3K 

56K 

1.0K 

11 

200 

3.6K 

62K 

l.Ui 

12 

220 

J.9K 

68K 

1.2M 

13 

244) 

4.3K 

75K 

1.3H 

15 

270 

4.7K 

82K 

a  •  j*t 

16 

300 

5.  IK 

91K 

1,6H 

IB 

330 

5.6K 

10  OK 

l.SK 

20 

360 

6.2tt 

11  OK 

2.0M 

22 

350 

6,  ax 

120K 

2.2K 

24 

430 

7.5K 

130K 

sockets 


LOW  PROFILE   SOCKETS 
Soldertail,    tin  plated, 

14  pin ..>.,, 10/?1,95 

16  pin .,,,, 10/S2.15 

18  pin 10/J2.75 

20  pin. ....,, IO/53.IO 

22  pin 10/53.50 

24  pin 10/53,60 

36  pin , 10/55 .  50 

^0  pii.  ■■  ■ ♦  10/56. 15 


WIRE  WRAP  SOCKETS 

3  level,  gold  plated, 

14  P^ 10/53.70 

1|  P1* 10/53.85 

JJ  Pjn i/fO.75 

24  pin ,...,,.,,.,,  ,1/51.00 

25  Pin ,,,...,.  1/51,  25 

36  pin...,,.. 1/51,35 

40  pin t .  .  1/51  75 


STAHBARD  SOLBERTAIL  SOCKETS 
Cold  or  tin  plated 


14  pin. 
16  pin. 
24  pin. 
28  pio. 
36  pin. 
40  pio. 


J        -        ■.       A       _       _ 


...10/53.70 

10/53.85 

♦•♦. .1/50,75 
.... .1/50.75 

1/51.00 

1/51.25 


TER«S:  Add  SOc  to  orders  under  $10  for 
postage  and  handling.  Other  item*  in 
this  ad  postpaid,  Callfomians  add 
t^s.  Please  give  us  your  street  ad- 
dress as  we  send  out  parcels  via  UPS. 

DISCOOTTIS;  For  ICs.  the  following 
discount  schedule  applies . 

Buy  10  ICs ... , take  10X  discount 

Buy  100  ICs take  20t  discount 

CREDIT  CARD  ORDERS /COD  We  do  not  ac- 
cept COD  orders,  but  BankAaericard*  & 
Mast  ere  Large'  ere  welcocce.  Give  all 
appropriate  Information  on  order;  or 
place  orders,  anytime  of  the  day  or 
night .  on  our  24  hour  phone  desk:' 


(415)  562-0636 


CAM 


V     I   1 


FTJID  OUT  ABOUT  OUR  OTHER  PRODUCTS 
COMPLETE  ylTH  ILLUSTEAT108S ,  BY  EE- 
Q0EST1UG  OUR  LATEST  FLYER.   THAMES  1 


184 


THANKS  AGAIN 

for  another  really  wonderful  year ! 


sCcd 


'  auw 


^Wtt 


4cd 


<7U4J 


01M  4 


CrtJib  Plrtfetd  sGAS 


Cv* 


dUf 


yvucr&us/  &  ci*    /?77 


ru/  &*jcm  t£c$ 


f/tety \4i77<?fAc4  /  £e  Miu7^^aio> . 


&      m 


JlMj-*"^ 


'UJUU  V?[jUjldM-       v 


J^A!*^0 


?i 


CAVE 


BILL  GOD&OUT  ELECTRONICS 
BOX  2355,  OAKLAND  AIRPORT.  CA  94614 


185 


iinm 


7400N  TTL 


917491ft 


wmm 


mm  -m 

5*741 1* 

scum 

W74144 

swum 

-17W 
SW742W 
5N7471N 
BN7*ftif 
SM?JI5W 
SN7425M 
SN742M 
SNTO7I* 
SH742W 

5*74374 
flit 

s*?439f* 


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FTK0033 


05"  High  Common  Cathode  Digit 
0,5"  High  Common  Anode  Digit 
,357"  High  Common  Cathode  Digit 
0.8"  High  Common  Cathode  Digit 
0.8"  High  Common  Anode  Digit 

0.8"  HIGH  DISPLAY  ARRAYS 


12  Hour, 

24  Hour, 

3y2  Digit  Clock  Display 
4  Digit  Clock  Display 

LED  LAMPS 

10  Red  LED  Lamps 

5  Mixed  Colored  LED  Lamps 
10  LED  Mounting  Clips 

5  Three  Piece  LED  Mounting  Adapters 

PHOTO  TRANSISTORS 

5  Flat  Lens  Photo  Transistors 
5  Round  Lens  Photo  Transistors 
3  Flat  Lens  Photo  DarJingtons 
3  Round  Lens  Photo  Darlingtons 


CARD  BACK 

$1.00 

FTK0040 

LOO 

FTK0041 

.75 

FTK0042 

2,00 

2,00 

FTK0050 

FTK0051 

7.00 

8.00 

FTK0400 

1,00 

FTK0401 

1.00 

1.00 

FTK0402 

LOO 

FTK0403 

1.00 

1.00 

FTK0405 

LOO 

1.00 

FTK0106 

FTK0106 


CARD  FRONT 


PHOTO  ARRAYS 

9-E!ement  Tape  Reader  Array 
12-Element  Card  Reader  Array 
Reflective  Opto  Coupler 

COUPLERS 

3  General  Purpose  Opto  Couplers 
Darlington  Opto  Coupler 

MPS  CLOCK  CIRCUITS 

Digital  Clock/ Calendar  Circuit 

(F  CM  7001) 
Digital  Clock/Calendar  with  BCD 

Outputs  (FCM7002) 
Direct  Drive  Digital  Clock  Circuit 

with  AC  Output  (FCM3817A) 
Direct  Drive  Digital  Clock  Circuit 

with  DC  Output  (FCM3817D) 
Direct  Drive  Digital  Clock/Calender 

Circuit  (FCM7015) 

KITS 
Automobile  Clock  Kit 


16.00 

24.00 

4,00 

LOO 
LOO 

7.00 
7.00 
5.00 

5.00 
6,00 


40.00 


THESE  PRODUCTS  ARE  PACKAGED  FOR  OUT- 
STANDING WALL  DISPLAY  APPEARANCE 


FULL 


IRCHI 


PRODUCT  LINE 


TO  FOLLOW 


DEALER'S  AND  WHOLESALER'S  INQUIRIES 
INVITED-PRICE  LIST  AVAILABLE. 

►BUY  WITH  PRIDE  THE  PRODUCTS  BUILT  BY 
THE  INDUSTRY'S  LEADER  -   "^^^^^ 


Ml 


Satisfaction  Guaranteed.  §5,00  Min.  Order.  U,S.  Funds. 

California  Residents  -  Add  6%  Sales  Tax 

Send  i  24c  Stamp  (postage)  for  a  FREE  1977  Catalog. 


NOW  OPEN  SATURDAYS 


1021  HOWARD  STREET 

SAN  CARLOS.  CA  94070 

PHONE  ORDERS  -  (415)  592-8097 


187 


SLEP 


ELECTRONICS 


CUSHCRAFT 

A147-4  BEAM  4E  L  1  46-148MHZ  ...  $1  5.95 
Al 47  11  BEAM  11EL  146  148MHZ  ..24.95 
A147  20T  BEAM  TWIST  20EL  144  147 


W      m-      a       4 


A147  22  SEAM  22EL  146  148MHZ 
ARX  2  RINGO  RANGER  1  35  1  70 

rV'    W       !     ^H  ■■  ■■■■p*BB:«I^VB^HIMBJBiajH1  I  ■  ■  ■  ■  I 

ARX  220  RINGO  RANGER  220-225 

MHZ  . 

ARX  450  RINGO  RANGER  435  450 

IV1     I       n     £.        %¥P       +■<■*■-■*         |pq|l-p«-||+||         PI* 


A220  7  BEAM  7EL  220-225MHZ  ... 
A220  1  1  BEAM  1  1EL  220-22BMHZ    . 

A449  11  BEAM  11EL449MKZ 

AFM-4  D  FOUR  POLE  144-148MHZ 

AR&  RINGO  50  54MHZ 

CR-1  RINGO  CITIZEN  BAND 

A50-5  6  METER  SEL  BEAM  ,..,._. 
A144  10T  OSCAR  145.9  BEAM  10EL 
A144  20T  OSCAR  145  9  BEAM  20EL 

A147  MB  MOUNTING  BOOM 

A432-20T  BEAM  432  20EL 


47.50 

69.50 

28.50 

28.50 

28,50 
1S.95 
22.95 
21.95 
53,50 
24,50 
28.50 
39.50 
3250 
47  50 
13.95 
4500 


LARSEN  ANTENNAS 

JM150  WITH  MM/LM  MAGNETIC  MOUNT 
2  METER  FM  ANTENNA  5/6  LOADED 
144-174  MHZ  WITH  RG-58AJ  COAX  ,37.00 
JM150  WITH  GC/LM  GUTTER  CLAMP 
MOUNT,  2  METER  FM  5/8  LOADED 
144-1  74MHZ  WITH  RG-58/U  COAX  .  .  37.00 


MINI  PRODUCTS 

HQ-1  HYBRID  QUAD,  ELEMENT  LENGTH 
11  FT.,  BOOM  4»  FT,,  TURNING  RADiUS 
6'2"  WT.  15  LBS  -  BANDS  6,  10,  15*  20 
METERS,  1200  PEP  FVB  RATIO  12  TO 
17DB.  52  OHM     .................  109.50 


HY-GAIN 

14A  VQ/WB  VERTICAL  10  THRU  40 

METERS    p'i. 67.00 

18  AVT/WB  ~  VERTICAL  10  THRU  80 

IVi   C     I     t   i"  1  *J  m     a     a\      ■     *■■■*■      ■     *    a      m  *     m      |     ay     a-     *      ■      w     *■*   f  -  W 

1BHT  HY  TOWER  10  THRU  80 

METERS    .  .  .  .  . 259,95 

TH3JR  TO/15/20  BEAM  750W  PEP  .  t  144,50 

203BA  3EL  20M  BEAM  2KW    149,95 

TH3MK3  10/15/20  BEAM  2KW(  3EL    199,95 
TH6DXX      SUPER      THUNDERBfRD      6EL 

10/15/20  BEAM ,,,.....  239.95 

204BA  4EL  20  METER  BEAM     179.95 

402BA  2EL  40  METER  BEAM    199.95 

244  HY  QUAD,  2EL  QUAD  10/15/20 
METER     ,,.,.,  ......  ..♦,..  ......  2 1 9.9  j 

2  BDQ  TRAP  DOUBLET  40  AND  80 

METER  49  95 

270  MOBILE   2  METER  5DB  GAIN  FIBER- 

G  LASS  2  METER     39.95 

MODEL  28  TWO  METER  8EL  YAGI 

D    CM    WWW  ■       *        a       ■■        p  1       *        t  a      «  .     a       «        p         ■        ■*■.■■■■■       «3     #    ■  UU 

269       RUBBER       DUCKIE       PORTABLE 
ANTENNA  2  METER  5/16  X  32  BASE  .  7.00 

274  RUBBER       DUCKIE       PORTABLE 
ANTENNA  2  METER  BNC  BASE 9.00 

275  RUBBER     DUCKIE    PORTABLE     AN 
TENNA  2  METER  PL  259  BASE  .  i  ;  .  .  .  7.00 

CI  CENTER  INSULATOR  FOR 

DOUBLET , 5,95 

El  END  INSULATOR  FOR  DOUBLET 
PAi  R  3.95 

14RMQ  ROOF  MOUNT  KIT  14AVQ,  18AVT 
VERTICAL 24.95 

271  BASE        STATION        MOUNTING 

BRACKET  FOR  270 4.95 

BN  86  FERR1TE  BALUN  10  THRU  80 
METERS 15.95 


MOSLEY 

CL-33      CLASSIC       BEAM      3EL 

METER  1KW 

TA  33    JR    3EL    BEAM    10/15/20 

300  WATTS 

TA-33  3EL  BEAM  10/15/20  1  KW    . 
TA-40KR      COM  VERSION      KIT, 

METER  TO  TA33 

SWL-7  SHORTWAVE    LISTENING 
11  THRU  49  METERS 


10/16/20 
.  .  224.00 
METERS 
.  ,  14500 
.  .  198.00 
ADD  40 
,  .  .  88.50 
DIPOLE, 
,  ,  ,41.25 


DI-2       DIPLOMAT      VERTICAL      GROUND 

PLANE  2  METERS 3000 

62SC  WALL  THRU  &  COAX  OUTLET  .  7.50 
C2-PK  -  WALL  PLATE  WITH  DUAL  COAX 

OUTLETS - 1  0.50 

CRS-PK      WALL      PLATE      WITH      SINGLE 
COAX  AND  8  WIRE  ROTOR  OUTLET  12.00 


NEWTRONICS 

4BTV  VERTICAL  10  40  METER     ....  79.95 

RM-75  ADD  ON  75  METER  RESONA- 

I   Vfi  W  V     *     #     *     ■>     a     ■     a     ■    a     ■-.  m     «     *    m*-  *     ■     m    a     m    j     ■     0     ■     b     v     *•     +      •   O  ■  v  *■• 

RM  75$  ADD  ON  75  METER  SUPER 

RESONATOR 28.95 

BBLT  144   5/S  MOBILE   WITH   TRUNK    LIP 

MOUNT  143-149MMZ   . 28.75 

CG-144     TWO    METER     COLINEAR    5.2DB 

GAIN  3/8"  X  24  BASE     ...♦,..  26.75 

CGT-144  TWO  METER  COLINEAR  5.2DB 
GAIN  WITH  TRUNK  LIP  MOUNT  ,,.39.95 
G6-144A       REPEATER       APPROVED      6DB 

GAIN  COLENEAR 52.95 

MO-1     54"    MAST    FOR    MOBILE    DECK    OR 

FENDER  MOUNT 15,95 

MO-2  54"  MAST  FOR  MOBILE  BUMPER 

MOUNT 15.95 

RM-10  RESONATOR  10  METER 10.75 

RMT OS  SUPER  RESONATOR  10 

METER wm  13.95 

RM-15  RESONATOR  15  METER  ,.,.11.75 
RM1&S  SUPER  RESONATOR  15 

METER ....  16.95 

RM  20  RESONATOR  20  METER    .  .  .  .  12.75 


RM-20S  SUPER  RESONATOR  20 

METER    .  ,  . . .  .  ,  19.25 

RM  40  RESONATOR  40  METER    ...      15  95 

RM40S  SUPER  RESONATOR  40 

M  t  1  En      .   .   .   .   .   .   ......   *.*<■   ■   *■.*..-**  J-  3u 

RM-75  RESONATOR  75  METER    .  .  .  .  16.95 

RM-75S  SUPER  RESONATOR  75 

M  ETER     ...*•.•»..+<■*  -t.  ..,*..  .  Jo  "v 

RM  80  RESONATOR  80  METER 16,95 

RM-80S  SUPER  RESONATOR    28.95 

RSS-2  RESONATOR  SPRING ,  .  .  5.65 

QD-1  QUICK  DISCONNECT 11,75 

BM  1    BUMPER  MOUNT  STAINLESS  STEEL 

v    I    "  wn  *         ■■     b-    ■     i     i     i     ■     p-  i     p    *    *     h    m     p     4     p-     >-•»*-*«     ft    *      I     Ib-3  w 

MM  1     COWL    MOUNT    WITH    SO-239    AND 

GCM-1    RAIN  GUTTER  MOUNT  3/8'*  ~  24" 

THREAD 7,50 

SSM  2  COMMERCIAL  BALL  MOUNT 

ONLY 1  3.50 

SSM-3    COMMERCIAL    STAINLESS    STEEL 

pr    F1  I    '  V  ^J       m     m    4     a      a     a     m     a     a     m.     m     m     a     a     *     m-    ■     *     ■*      m-    m-    a      *     a  I    .  _?  3 


CDR  ROTORS 

HAM  II  ROTOR  WITH  CONTROL   .  .  139,50 
CO  44  ROTOR  WJTH  CONTROL    ...119,50 

ROTOR   CABLE  S  CONDUCTOR   2/18,6/22 

GAGE 16  FT. 

RG-8/U      LOW      LOSS     FOAM     COLUMBIA 
SUPERFLEX     COAX    WITH     PL-259    EACH 

END.  50  FEET 12.50 

100  FEET , 23.00 

ANTENNA  WIRE  #17  BARE  COPPERWELD 

STRANDED  7/25  100  FEET 3,60 

PL  259  COAX  CONNECTORS     .60 

RG-8/U     LOW     LOSS     COLUMBIA    SUPER- 
FLEX  CABLE  500FT  REEL 120,00 

RG-58/U     LOW     LOSS    FOAM     COLUMBIA 
SUPERFLEX   WITH    PL  259  EACH   END,  50 

FEET  ....  . .  7.00 

100  FEET     12.00 


BARKER  &  WILLIAMSON 

MODEL  30O2W  UNIVERSAL  HYBRID 
COUPLER  PHONE  PATCH  WITH  BUILT-IN 
COMPREAMP.  THE  BEST  OF  PHONE 

MODEL  375  PROTAX  ANTENNA  SWITCH 
WITH   AUTOMATIC  GROUNDING,  6  POSI 

TION  REAR  MOUNTED  SO  239     18.95 

MODEL  376  SAME  AS  ABOVE  ONLY  5 
POSITION  SIDE  MOUNTED  SO-239  .18.95 
CC    50       DIPOLE       ANTENNA       CENTER, 

WEATHER  PROOFED     7.50 

MODEL       377       ANTENNA       COAXIAL 
CHANGEOVER     RELAY,     DC    TO    1 50MHZ 
115V/60HZ.    SWITCHES  ANTENNA   FROM 
TRANSMIT  TO  RECEIVE.  SO-239 
CONNECTORS    ....,,... 16.50 


P.O.  BOX  100r  HWY.  441,  DEPT.  73,  OTTO,  NORTH  CAROLINA  28763 


WE  PAY  SHIPPING  VIA  UP.S.  OR  BEST 
WAY  OH  ALL  ADVERTISED  ITEMS; 
TRADES  TAKEN  ON  NEW  EQUIPMENT. 
WRITE  FOR  SPECIAL  PACKAGE  PRICE 
ON  COMPLETE  STATIONS.  SATISFAC 
TION  GUARANTEED.  WE  ACCEPT 
MASTER  CHARGE,  N.C.  RESIDENTS  ADD 
4%  SALES  TAX  PHONE  BILL  SLEP 
704-524  7519  MONDAY  THRU  FRIDAY 
8:30-  6:00  PM, 


188 


ELECTRONICS  *||llH PWW 


r* 


ATLAS 

210X  80  THRU  1  OM    ........ 

215X160  THRU  1  5M  .  . 

21  OX  OR  21  5 X  WITH  NOISE 

ID    m^  f~\   1^1    !*■    C-  TT  ■       P       *      d       *       m       1        hi       hri       ■**#.« 

AC     CONSOLE     220CS     WITH 

BREAK  IN  CW  .  .  . 

AC  CONSOLE  220CS     , 


,  .  .  $679.00 
....  679.00 

.  .  .  .  719.00 

VOX/SEMI 

.  ,  ,  .  194.00 

.  .  .  .  147.00 


PORTABLE  AC  SUPPLY  200PS  .  .  .  .  10000 
DMK  PLUG-IN  MOBILE   MOUNT,  WITH  DC 

CA6LE     _  ,     ,  .  . 48.00 

DCC  BATTERY  CABLE     12.00 

DD-6B  DIGITAL  DIAL , 229.00 

MT  1  MQBfLE  ANTENNA  MATCHING 

TRANSFORMER 27.00 

PC  120  NOISE  BLANKER  CONVERSION 

KIT ,  52.00 

VX  5  VOX  CONVERSION  KIT  FOR  AC 

CONSO  LE     49.00 

206  AUXILIARY  VFO  WITH  EXTENDER 
FREQUENCY  COVERAGE  FOR  ALL 
ATLAS  TRANSCEIVERS 299.00 


DRAKE 

R-4C  RECEIVER  160  10M    599.00 

4-NB  NOISE  BLANKER  R  4C 70-00 

FILTERS  250HZ,  500HZ,  1,5HZ     .   ea.  42.00 

SPR  4  RECEIVER 629.00 

5  NB  NOISE  BLANKER  SPR-4 70.00 

DC  PC  1  2V  POWER  CORD    ..,,.,....  5.00 

SCC4  100H2  CALIBRATOR    20.00 

CRYSTAL  KIT  AMATEUR  BANDS  ,  .  31,20 
SSR-1     GENERAL    COVERAGE    RECEIVER 

.5  TO  30MHZ ,  . 350.00 

DC-PC  SSR-1  DC  POWER  CORD  ......  5.00 

T-4XC  TRANSMITTER  160  1  0M  .  599,00 

TR4C  TRANSCEIVER  B010M  .  .  .  ,  599.95 
34PNB  NOtSE  BLANKER  TR-4C    .  ,  ,  100.00 

MMK-3  MOBI  LE  MOUNT 7,00 

RV4C  REMOTE  VEO  TR  4C 120.00 

AC-4  POWER  SUPPLY  FOR  ALL  DRAKE 
TRANSMITTER  TRANSCEIVERS  .  .  120.00 
DC  4  12V  DC  MOBILE  POWER 

SUPPLY 135,00 

TR-33C  2  METER  FM  TRANSCEIVER  12 

LnAiNlM  t  L5    .    ...  ^   ..*.....  .   ******   ZiSiD  j 

AA-10  10  WATT  2  METER  AMPLI- 
FIER   .49.95 

AC  10  POWER  SUPPLY  TR  22,  TR  33, 

TR  72 49  95 

MN  4  ANTENNA  MATCH  BOX  ....  110.00 
MN-2000  ANTENNA  MATCHBOX   .  .  220.00 

MS-4  SPEAKER 24.95 

W-4  WATTMETER  1,8  TO  54MHZ    ...72.00 
7072  HAND  HELD  MIKE    ..........  1  9.00 

7075  DESK  TOP  MIKE  WITH  VOX 

5iVI  I  i#r    ■■■.*»...* J^.UU 

RCS-4  REMOTE  CONTROL  ANTENNA 

SWITCH 120.00 

HS-1  HEADPHONES 1000 

TV  3300LP  LOW  PASS  FILTER  19.95 

DSR-2  VLFHF  DIGITAL 

RECEIVER    ,  , 2,950.00 


TEMPO 

TEMPO  ONE.  5  BAND  SSB  TRANS- 
CEIVER   . T  H  t  T  ,  ,  T  399,00 

TEMPO  ONE  AC  POWER  SUPPLY  .  .  .  99.00 
TEMPO  VF/ONE  EXTERNAL  VFO  .  109,00 
TEMPO       DFD/ONE       DIGITAL       DISPLAY 

TEMPO  ONE .  189.00 

TEMPO    2020    SSB/AM    TRANSCEIVER    SO 

TO  1QM  115V/12VDC  P/S 75900 

TEMPO    FMH   2  METER.  6CH  HAND  HELD 

FM  TRANSCEIVER 199.00 

TEMPO  VHF/ONE  SYNTHESIZED 
DIGITAL  READ-OUT  2  METER  10  WATT 
TRANSCEIVER,  NO  CRYSTALS  TO 

BUY 495.00 

TEMPO  SS8/ONE  SSB  ADAPTOR  FOR 

UHF/ONE    225,00 

TEMPO  130A10  130  WATTS  OUT  1  OW 

DRIVE 179.00 

TEMPO  80A1 0  80  WATTS  OUT  1  0W 

DRIVE 139.00 

TEMPO  5OA10  50  WATTS  OUT  1  0W 

DRIVE  99  00 


TEN  TEC 

TRITON  IV  MODEL  540  TRANS 

\*  *Z  I  V  Cn     ..lt.i.......... 

252G  POWER  SUPPLY 
252G  POWER  SUPPLY/VOX 

207  AMMETER 

245  CW  FILTER  ..,.,..., 
ARGONAUT  MODEL  509  .  . 
40B  LINEAR  AMPLIFIER  .  . 
210  POWER  SUPPLY  1  AMP 
251  POWER  SUPPLY  9  AMP 
206  CRYSTAL  CALIBRATOR 

208  CW  FILTER    ........ 

HR5A  KEYER 

KR20A  KEYER   .  .  . 

KR50  KEYER    ,  .  . 


.  699.00 
.  .  99.00 
♦  129,00 
,  .  14,00 
.  .  25.00 
329.00 
,  159  00 
27.50 
...  79.00 
.  .  ,  .  26.95 
.  .  .  .  29.00 
.  .  .  .  38.50 
.  .  .  67.50 
.  .  .  110.00 


-«-«** 


BRIMSTONE 

MODEL    144  2  METER    FM  TRANSCEIVER 
25    WATT     143     TO     149.99MHZ    DIGITAL 
DIALED   SKHZ  STEPS,  NO  CRYSTALS  TO 
BUY  142MHZ  MARS  COVERAGE 
OPTIONAL .  .  ,  650.00 

COMCRAFT 

CST  50  VHF  TWO  BAND  TRANSCEIVER  2 
AND  1ft  METERS.  DIGITAL  FREQUENCY 
SYNTHESIS  142  TO  149.995MH2  AND  220 
TO  225  MHZ  25  WATTS ,  869.00 

SHORE 

526T  DESK  TOP  MICROPHONE  WITH 

PRE  AMP  .......................  36.50 

444    SSB    DESK    TOP  MICROPHONE   WITH 
OFF -ON  VOX  SWITCH  PTT    ........  34.50 

404C  HIGH  IMPEDANCE  MAGNETIC 
HAND-HELD  MICROPHONE  FOR  SSB  PTT, 
IDEAL  FOR  SWAN,  ATLAS 27.00 


MILLEN 

92200  ANTENNA  MATCHBOX  ALL  BAND 
2KW ..,.*-....,.•.•• 199,00 

92201  JR     ANTENNA     MATCHBOX     ALL 

BAND  300  WATTS    , 1  38.00 

9Q652  SOLID  STATE  GRID  DIP  OSCIL- 
LATOR 9  VOLT  BATTERY  OPERATED 
WITH  COI  LS  1.7  THRU  300MHZ 

SUPPLI  ED ,.,,,.  13800 

SWAN 

700CX  TRANSCEIVER 649.95 

117XC  CONSOLE  SPKR/PS    T59.95 

14  1  17  DC  MQBfLE  P/S     189.95 

510X  CRYSTAL  OSCILLATOR    .....  67.95 

VX-2  VOX 44.95 

FP-1  PHONE  PATCH 64.95 

SWR  1  POWER/SWR  METER  0-1  KW(  3.5- 
150  MHZ  SO-239  CONNECTORS  ....  21.95 
WM  2000    IN    LINE    WATTMETER  SCALES 

TQ   JKW  4Q  Qf% 

■      *■— r         m*^    ■  ^    W  ^  b       v       *       v       w      w       p       r       *■       m       r       m        mm        r        m       ■       *•       ai       41       ■.       tv       ■       *      **   "J*"  '■  ^f  '** 

1200X  LINEAR  AMPLIFIER  1200 

MARK  II  LINEAR  AMPLIFIER  2KW   849  95 

SS  16B  KIT 9995 

45  ALL  BAND  MANUAL  SWITCHING  1  KW 

PEP  MOBILE  ANTENNA     114,95 

742     TRIBAND     20-40-75     METER     ELEC 
IRONICALLY       TUNED       AUTOMATIC 
BAND-SWITCHING,  500  W.PEP 79.95 

REGENCY  TRANSCEIVERS 

HR  312  FM  2  METER  30W 26900 

HR-6  FM  6  METER  1  5W 229.00 

HR  220  FM  220MHZ  10W 23900 

HR  440  FM44C  MHZ  1 0W    349,00 

P  110  AC  P/S  117V/12VDC  REGULATED  5 
AMP  AQ  <|r 

NYE  VIKING 

CODE  KEYS  SPEED-X  MODEL  114-310  003 
STANDARD        KEY,       NICKEL       PLATED 

HARDWARE  WITH  SWITCH     B.25 

MODEL      114-310004     STANDARD      KEY, 
NICKEL       PLATE       HARDWARE       WITH 
SWITCH  AND  NAVY  KNOB  ......  9  10 

SSK  1      DUAL      PADDLE      SQUEEZE      KEY 

NICKEL  PLATED 23.95 

MODEL  114  404  002  CODE  PRACTICE  SET 
WITH    KEY,  OSCILLATOR,  AMPLIFIER  2" 
BUILT-IN  SPEAKER.  HEAVY  DUTY  BASE, 
TAKE  9V  BATTERY.  NOT 
INCLUDED '     _  .  .  18.50 


BEARCAT 

MODEL      101,      16     CHANNEL     SCANNER, 
3050MHZ    146  174MHZ.    416  512MHZ,   NO 

CRYSTALS  TO  BUY  . 290.00 

W2AU  BALUN.  2KW  PEP,  3  TO  40  MHZ  1    1 
MATCHES   50  OR    75  OHM  UNBALANCED 
COAX     LINE     TO     50     OR     75    OHM    BAL- 
ANCED LOAD,  BUILT-IN  LIGHTNING 
ARRESTOR 1  Z95 


P.O.  BOX  100,  HWY.  441r  DEPT.  73f  OTTO,  NORTH  CAROLINA  28763 


WE  PAY  SHIPPING  VIA  UPS,  OR  BEST 
WAY  ON  ALL  ADVERTISED  ITEMS; 
TRADES  TAKEN  ON  NEW  EQUIPMENT. 
WRITE  FOR  SPECIAL  PACKAGE  PRICE 
ON  COMPLETE  STATIONS.  SATISFAC 
TtON  GUARANTEED,  WE  ACCEPT 
MASTER  CHARGE,  NX.  RESIDENTS  ADD 
4%  SALES  TAX.  PHONE  BILL  SLEP 
704B247519  MONDAY  THRU  FRIDAY 
8:30     6:00  PM. 


J 


v£ 


/??* 


189 


(214)823-3240 


ELECTBMICS 

PO  BOX  1944SE 
DALLAS  TX  75213 


E3 


^S 


X 


FEATURES: 

Output  adjustable  from  3  to  30 
Volt*  DC 

Adjustable  Current  Limiting  to  15 
Amps 

Special  Pre-Regulator  Circuit  elim- 
inates need  for  massive  heatsinks 
Better  than  1%  Load  &  Line 
Regulation  from  0  to  15  Amps 
Low  Ripple  Output 
Heavy  Duty  10  lb.  transformer 

KIT  INCLUDES: 
Transformer 
Heatsink  (drilled) 
Semiconductors  (diodes,  trans- 
istors, etc.) 

All  Components  (resistors,  caps) 
Transistor  mounting  hardware  and 
insulators 

Drilled  &  Plated  PX.  Board 
Wire 


Not  only  is  the  PS— 12  able  to  supply  a  continuous  15  AMPS  of  low  ripple,  regulated  DC  Voltage, 
but  it  is  also  variable  from  3  to  30  volts!  Use  it  as  a  building  block  for  a  fantastic  bench  supply* 
The  chassis  work  is  up  to  you  —  go  fancy  with  meters  and  lights;  or  plain  with  a  metal  plate.  Either 
way  we  get  you  out  with  a  quality  kit  at  a  super  low  price  and  we  guarantee  your  satisfaction. 

INCLUDE 


•  4  Digit  LED  Readout 

•  Simulated  Swinging  Pendulum 

•  Tick-Tock  sound  matches  pend- 

•  ulum  swing 

•  Electronic  Tone  Chimes  the  Hour 
(ie:  3  times  for  3  o'clock) 

•  Quality  Components  &  P.C,  Boards 

•  Transformer   for  1 15  VAC  in- 
cluded. 


SHIPPING 


E  CLOCK  KIT 


Urge  W*  LED 

Readout 

l 


All  CMOS 

IC  Construction 


$44.°° 


3"  Speaker 


* 


*  r 


c 


POSTPAID 

NO  CASE  INCLUDED,  LET  YOUR 

IMAGINATION  RUN  WILD  AND  DESIGN 
YOUR  OWN.  WE  SUPPLY  ALL  THE 
ELECTRONICS. 


Simulated  swinging 

pendulum  uses 

LED*s 


Tex.   Res. 
add  S%  tax. 


NO 

SEND 

MO, 


,MC 


BankAmericard 


wdkma  feu 


1 90 


75219 


(214)  823  3240 


[?a  ms  19442  e  mm  mm 


10.7 

CERAMIC 
FILTER.  MURAT  A1 

5FG  10.7  FOR  FM 

APPLICATIONS  (wideband] 

SPECIAL  PRICE 

REDUCTION 

Fwhile  they       <^4    RQ 

last 


PNP 

POWER 

TA8  TRANSISTOR 

SIMILAR  TDTIP30 

IN  SPECS,   HOUSE  NO. 

GUARANTEED 

3/1.00 


TOUCHTOIME 

ENCODER 

KIT 

SINGLE    IC  GENERATES   THE    STAN- 
DARD  16  TONE  PAiRS   FOR  TOUCH- 
TONE      DIALING.  KIT     FEATURES: 
Small  Size  (1.5  x  2.25'} 
NO  Tuning  Required 
PTT  Circuit  has  built-in  T  second  delay 
Low  Level  output  is  adjustable 
Audio  output  Circuit  for  tone  monitoring 
Or  acoustic  coupling 
Kit  includes,  all  parts 
Plug  compatible™ ith  DIGITRAN® 
KEYBOARDS 
Complete  with  PC  Board 


TE-01  $12.00 


Same  as  above  but  less  Audio  output 
and  PTT  circuit  Smellar  size  permits 
use  with  h and i talk iei.      sirj.oo         TE— 02 


l- r 


HARDWARE 

A  VERY  USEABLE 

ASSORTMENT  OF 
2-56r  4-40,  6-32  and  8-32 
SCREWS  AND  NUTS 

A  FULL  225 gm& 
OF  NEW  HARDWARE 


ELECTROLYTIC 
CAPS 

WE  BOUGHT  A  WHOLE 
TRUCKLOAD  OF  VARIOUS 
VALUES  FROM  20  mfd  to 
10OO  mfd  ALL  FROM  15  to 
50  VOLT  RATINGS. 


PS-01A  POWER 
SUPPLY  KIT 


A  COMPACT,  WEIL  REGULATED 
TRIPLE  OUTPUT  POWER  SUPPLY. 
GIVES  +5VDC  &  T.5A  and  +15  $  15QMA 
AND-15@150MA.  THE  PS-OTA  USES 
THE  SUPERFOR  78L  SERFES  OF  3 
TERMINAL  REGULATORS, 


SPECS: 
Voltage; 

Ripple; 
Regulation: 


+5&1.5A 
+J5@1SQMA 
Less  than   lOmv 
Load  SOmv 
Lina   lOOmv 


$14.95 


PS-01B    AS    ASOVE    BUT 
OUTPUT  INSTEAD  OF +.15. 


3772 


IBOWfiOV  NPN 

POWER  TRANSISTORS 

Most    popular    unit    for    high 

currant      power     supplies     Or 

audio  work. 

NEW-GUARANTEED 


AIRCRAFT/MOBILE 
CLOCK  TIMER  KIT 

A  FULL  6  DIGIT  LED  READOUT  CLOCK  THAT  GFVES  24  HOUR  (ZULUF  REALTIME 
AND  E  LAPSED  TIME  IN  SECONDS,  MINUTES  AND  HOURS  UP  TO  24  HOURS-  READOUTS 
CAN  BE  TURNED  OFF  OR  DIMMED.    PC  BOARDS  ARE  SMALL  TO  FIT  INSIDE  A  STAN- 


DARD INSTRUMENT  CASE  {Ztt "  Dia.} 


12V 
NEG  GNO 


MK-03 


$26.95 


KIT  IS  SUPPLIED  WITHOUT  SWITCHES  OR  CASE 


FEATURES: 

Real  Time  424  hr,F 

Elaps&d  Time 

2MOSChips 

,3"  LED  Read&utSi 

Special  Noise  FiFter 

Quality  plated  boards 


2N3904 

NPN 

General  Purpose 

Switching 

12/1.00 


2N2222 

UNMARKED 
TO-18     NPN 

12/1.00 


2N4861 

N  CHANNEL  FET 
GEN.  PURPOSE  FET 

3/1.00 


6  DIGIT  ALARM 
CLOCK  CHIP 

MM5375AB 
NEW  LOW  PRICE! 

$2.95 


SCREAM! 

AS  LOUD  AS  YOU  WANT,  BUT  OUR 
LITTLE  WARBLE  KIT  IS  LOUDER! 
COMPLETE  DUAL  TONE  WARBLE 
ALARM  WITH  10  WATT  OUTPUT. 
INCLUDES   ALL   PARTS  AND  BOARD. 

$2.50 


GREAT  FOR  BURGLER  ALARMS 
6-15VDC 

{Speaker  not  inctudedji 


I^PUII^IHHVl    i^y      'l^1'*^ 


AUDIBLE 

CONTINUITY 

TESTER  KITS 

A  FANTASTIC  LITTLE  DEVICE 
THAT  HAS  A  HUNDRED  AND 
ONE  USES  AROUND  THE  SHOP 


$1.95 


AND  HOME, 
USES: 

Code  Practice 
Continuity  Test 
Transistor  Test 
LED  &  DiOm  Test 
Tune  varies  with  resistance 
REQUIRES  3  to  6  VOLT  BAT 
(not  included.! 


OHM 


COAX 


SUPER  QUALITY  COAX 

SLIGHTLY  LARGER  IN 

DIAMETER  THAN  RG-74 

BUT  BETTER  SPECS 

100  ft.  ROLL 

$3.99 


aaauBSDiii 


ELECTRONIC 

IESFGN 


*Jk     *Vln 


4fri 


s»    iimfti  'i*A 


SORRY  -  NO  COD  i 
CHECK  OR  MO. 
ADD  5%  FOR  POSTAGE 
TEXAS 


FOREIGN  ORDERS  ADD  10% 

120&FOR  AFRMAFL) 

ORDERS  UNDER  S10,  ADD  60c  HANDLING 

RESIDENTS  ADD  5%  SALES  TAX 


Monthly    Pri*e    GJVin    for    best    circuit. 

1.  AH    entries    become    property 
of  BULLET. 

2.  Entry   should  include  schematic 
and  circuit  description. 

WATCH  THIS  SPOT  FOR  WINNER'S  NAME! 

STDO,  GIFT  COUPON  FROM  BULLET 


191 


MICROPROCESSOR  DISPLAY 

STATION 


Those  units  were  part  of  a  complex  computer 
system.  The  display  station  contains:  50  key 
numeric/ block  alpha  keyboard  plus  others. 
Display  capacity  is  768  (12  line  of  64),  384. 
256,  128  or  so  on  depending  on  size  of  charact- 
ers desired.  The  viewing  screen  of  the  3"  CRT 
utilizes  a  high  contrast,  low  persistence,  emer- 
ald green  phosphor.  Each  display  character  is 
composed  from  a  5x7  dot  pattern  and  registers 
clearly  and  sharply  against  a  dark  background. 
Controls  provided  are;  on/off;  brightness; 
focus;  and  character  height.  The  character  size 
may  be  adjusted  from  approximately  type- 
writer size  up  to  V  depending  upon  the  num- 
ber of  characters  displayed.  Character  genera- 
tion was  in  control  unit,  which  is  not  supplied. 
Unit  contains  keyboard,  CRT,  drive  circuits, 
with  data  book  and  schematics.  Use  2513, 
2516,  or  other  alpha/numeric  generator  LSI 
chips.  Great  for  microprocessor  input  and  out- 
put device.  Units  are  used,  from  airline  reserv- 
ation systems,  stock  markets,  hotel  reservation 
systems,  etc. 
Sh,  Wt.  40  Lb*  ,  .  .  ,  6NB60336.  .      ,   $7950 


TOUCH-TONE  DATA  ENTRY 
AUDIO  TERMINAL 

Transcom  RCT203  is  a  versatile  data  terminal 
that  delrvers  instant  visual  verification  of  send- 
ing and  receiving  hard  copy  of  audio  touch  tone 
data,  uses  regular  telephone  lines.  Use  two  (2) 
of  these  to  send  and  receive  with  monitoring  of 
visual  and  audio  tone  at  both  stations.  Unique 
strip  printer  gives  hard  copy  by  use  of  an  elec- 
trostatic 5*7  dot  matrix  printer,  with  3/8"  high 
characters,  5  characters  per  inch,  35  digits  dis- 
played at  at!  times.  Units  come  complete  with 
power  supply,  strip  printer,  touch  tone  key 
board  with  oscillators,  decoders,electronic  logic 
and  other  related  electronics. 
Sh.  Wt,  20  Lbs  ,  .  .  .  6MI6026S.  ,  .  .  $49.00 
2  for  $89,88 6M 1 6 0268  .  .  .  .  $89,88/2 


VIATRON  DATA  MANAGEMENT 
STATION -SYSTEM  21: 

Microproscessor  assembly,  complete  with  key- 
board, CRT,  etc+  Checked  out  and  in  working 
condition.   Only  a  few  left . $595.00 


B&  F  ENTERPRISES 

119  FOSTER  STREET 
PEABODY,  MA,    01960 
(617)  531-5774/532-2323 


BanxAmericarq 


BIG  BRUTE  SPEAKERS 
by  COMM, 


BR  708 


BR  420 


BR  MB10 


New  surplus  car  "stereo"  or  "CB"  speakers  for 
super  sound.  We  purchased  a  special  quanity 
of  the  super  speakers,  which  were  developed  for 
true  hi-fi  reproduction.  They  are  of  unique  de- 
sign, matched  and  balanced  for  stereo  and  hi-fi 
systems.  All  are  8  ohms  voice  coils.  We  have 
only  four   (4)   types  at  this  time.     Surface  or 

flush  mount,   Sold  at  audio  net  user  price 

way  below  list  price! (see  pictures). 
Order  No.  Sh      Mag  pwr  Prices 

Mfg.  No.    Wt       Wt.  wts.  each  pair 

BR  MB10  2  20  80  Si  1.88  $1938 
BR  708  1  8  30  $5,88  $10*88 
BR  920*  2  20  80  $8.88  $1188 
BR  420*  2  20  80  $8.88  $15.88 
^ 


DIGITAL  CLOCK 
&  RADIO  ALARM 


New  surplus,  by  Copal-  This  unit  was  part  of 
a  radio  alarm  clock,  lighted  digital  movement, 
runs  on  115  V  60  Hz.  Movement  has  an  8  min- 
u  te  snooze  feature,  10  amp  SPOT  Alarm 
switch,  with  shaft  for  time  and  alarm  set  on 
front  face.  The  last  time  we  had  this  type  of 
clock  movement  the  sold  out  only  a  few  weeks 
after  the  catalogs  were  mailed...... 

Sh.  Wt.  6  oz 6D60316 $5.88 

4  for  $20,00.  .  -  .     6D60316    ....  $20.00/4 


o 


Urv 


L       U        J 


SENTRY 
SOLID  STATE 
IGNITION 

Solid  state  ignition  saves  your  points,  plugs 
and  gas,  ignition  parts  last  up  to  4  times  longer. 
Installs  in  all  trucks,  vans,  cars,  and  boats 
quickly  and  simply,  6  or  12  Volt  systems.  Im- 
prove mileage  and  performance:  no  more  high- 
speed  miss  or  spark  fall -off.  How  can  you  not 
afford  to  buy  this  super  item  at  our  price? 

Sh.  Wt.   2  Lbs.  .  .  ,  .6MI60110 $9.75 

2  for  318.00,  .  .  .  .6MI60110  ....  $18.00/2 


master  cftarge 


PHONE  ORDERS  WELCOME! 
BankAmericard  and  Master  Charge  Accepted 

TERMS:   Add  Postage 

FREE  CATALOG! 

Every  order  includes  our  latest  catalog 
and  insures  you  of  a  place  on  our  mailing  list 


MODERN 
STANDARD  TELEPHONES 


A^SVWV-VVVArVWV^VAWWW 


A  complete  modern  phone  ready  for  instant 
use.  Factory  rebuilt.  Available  in  white, 
black,  beige,  pink,  red,  green,  &  blue.  Ideal  for 
an  extra  phone,  use  on  intercoms,  private  sys- 
tems, extensions,  etc.  Easy  3  wire  hook-up. 
With  hand  set,  induction  coil  and  cable.  Phones 
shipped  may  vary  slightly  from  photo.  We  have 
many,  many  different  types  and  styles.  When 
specifying  a  color,  give  up  to  3  choices  in  order 
of  preference.  Some  may  not  have  ringers. 

t  Standard  Desk  Dial  Phone 

Sh.  Wt  8  Lbs  (black)    .  .6VL60440.  .    S12.S0 

t  Standard  Wall  Dial  Phone 

Sn.Wt.  8  Lbs  (black)    .  .6VL60442.  .   $12,50 

t  Standard  Desk  Touch-Tone  Phone 

Sh.  Wt.  8  Lbs  (black)  .  .6VLG0444.  +  $24.50 
Sh.  Wt.  8  Lbs  (color).  .  .6VL60445.  .    S27.50 

t  Standard  Wall  Touch -Tone  Phone 

Sh.Wt.  8  Lbs  (black)  .  .6VLS0446.  .  $24.50 
Sh,  Wt.  8Lbs(colorh  .  .6VL60447.  .   $27.50 

t  2  Line  Standard  Desk  Dial  Phone 

This  phone  has  a  twist  key  to  switch  in  2  lines 
over  the  same  phone, 
Sh.  Wt.  8  Lbs  (black)    .  ,  6V60448  .  .   $24.50 

t     CALL  DIRECTOR  office  style  desk  dial 
phone:    10  line  phone  with  hold  and  intercom 
buttons, 
Sh.  Wt.    15  Lbs  ...  .  6V60449  ,  .  .  .   $49.50 


COLOR  TV 
CHASSIS 


New  surplus  solid  state  TV*  color  chassis  and 
related  parts,  to  make  an  outstanding  color  TV 
for  peanuts.  With  these  chassis  and  parts  you 
can  build  an  outstanding  color  TV  for  around 
$100.00.  Chassis  and  parts  are  from  13*%  15", 
17'%  and  19"  table  color  TV's,  They  are  curr- 
ent production  models.  All  chassis  supplied 
with  shop  tech  manuals  and  data. 

t  13"  TV  CHASSIS  with  tuners  and  controls. 

6Z60175. $49.50 

t  15"  TV  CHASSIS  with  tuners  and  controls, 

6Z60174 $49,50 

t  17"  TV  CHASSIS  only  (no  tuners) 

6Z60173 $29.50 

t  19"  TV  CHASSIS  only  (no  tuners} 

6260172.  .  .      .....   $29.50 

t  17"  Outrun -lrv Line  matrix  Picture  Tube 

6Z60176*  .  ■  . $49.50 

t  VHF  Tuner  (for  17"  and  19"  sets) 

6Z60303 $8.50 

t  UHF  Tuner  (for  17"  and  19"  sets) 

6Z60304 $2.50 

t  Antenna  Telescope  .  .  .  5MI00419.  .  .  SI. 50 

t  TV  Speaker  .  .  .  .  .  6Z60177 S3.50 

t  Binding  Post  Assembly,  UHF,  VHF 

4MI00422,  .......  .$1.50 

t  2nd  Stage  Hi  Voltage  Boost,  13"  and  15"  sets 

6260178 $3.50 


$239.95 


Hy-Gain  9  (model  2679)  sells  for  $239.95  with  Hy-Gain 
426  AM/FM/CB  antenna,  Deduct  $20.00  if  you  don't 
want  antenna. 


The  following  Hy-Gain  23-channel  radios  can  be  remanu- 

factured  to  FCC  40-channel  specifications  after  January 
1,  1977  and  FCC  type  acceptance. 

681 ,  682,  2680,  2681,  2682,  2683,  2679,  3084 
If  you  currently  own  one  of  these  radios,  a  40-channel 
certificate  may  be  obtained  from  your  Hy-Gain  dealer. 


marketing 


introduces 


out-of-sight  CB 

that's  ready  for 

40  when  you  are! 


Now!  Get  the  Hy-Gain  CB  system  that's  ready 
for  40  channels  when  you  are.  Our  out-of- 
sight  Hy-Gain  9  (Model  2679)  citizens  two- 
way  transceiver  and  Hy-Gain  426  AM/FM/CB 
40-channel  antenna. 

The  great  Hy-Gain  9  transceiver  goes  out  of 
sight  in  the  trunk  or  under  the  seat.  All  that's 
visible  is  the  hand-held  MSR  (microphone, 
speaker  and  radio)  Control  Unit  with  built-in 
mic  and  speaker.  Disconnects  easily.  So  you 
can  take  it  with  you.  Or  store  it  away.  Superb 
performance  includes  TV  I  filter  to  help  pre- 
vent TV  interference, 

After  January  1  and  FCC  acceptance,  just 
send  Hy-Gain  the  certificate  that  comes  with 
the  Hy-Gain  9.  And  $25  for  remanufacture. 
Hy-Gain  will  remanufacture  your  radio  for  all 
40  channels!  Offer  expires  June  30,  1977. 


The  high  performance  Hy-Gain  426  40- 
channel  AM/FM/CB  antenna  goes  great  with 
the  Hy-Gain  9.  Replaces  standard  auto  an- 
tenna, Looks  like  original  equipment.  So  you 
know  it's  CB.  But  rip-off  artists  don't! 


m 

c 
c 

01 


am 


We  keep  people  talking 


C&S  MARKETING  ASSOCIATES 


P.O.  Box  J  65 

Algood  TN  38501 

Call  Toll  Free  800-251-6771 

In  Tennessee  call  800-262-6706 


6  Digit  LED  Clock  Kit  - 12/24  hr. 


GTY.12 

ea.     OR  MORE 


QTY 
3      6-11 


QTY 


6  LED  Readouts! FND-359  RedH  com.  cathode) 
MM5314CtockChip(24pin} 

S^tehS01*  LARGE  .4"  DIGITS! 

6  Capacitors  ORDER  KIT #850-4 

BR^ors  AN  INCREDIBLE  VALUE! 

2'1-Mole*  pir^S  for  IC  socket 


KIT  INCLUDES 
•  INSTRUCTIONS 
•QUALITY  COMPONENTS 
•50  or  60  Hz  OPERATION 
•12or24  HR  OPERATION 

Kit  N850-4  will  furnish  a  complete  set  of  clock  components  as  listed. 
The  only  additional  items  required  are  a  7-12  VAC  transformer,  a  circuit 
board  and  a  cabinet,  if  desired," 

Printed  Of  curt  Board  for  kit  #  850-4  (etched  ft  drilled  fiberglass) , „«„.„„„„„„„. $2.95 

Mini-Brhe  Red  LED's  I  for  colon  in  clock  display]  pkg.  of  5.- ..........   LOO 

Molded  P lu g  Transformer  11 5/ 10  V AC  {wrthcord} 2.50 

MOTE-  Entire  Ciock  mav  be  assembled  on  one  PC  Board  or  Board  may  be  cut  to  remote  displav 
Kit  ff  850-4  will  fit  Plexiglss  Cabinet  II. 


CABINET  I 
3"Hf61/4"W.5fc"D 

CABINET  II 
2VH,5"W,4"D 

ANYSIZE/COLOR 


PLEXIGLAS 

CABINETS 

Great  for  Clocks 
or  any  LED  Digital 
project.  Clear-Red 
Chassis  serves  as 
Bezel  to  increase 
contrast  of  digital 
displays. 

Black,  White  or 
Cover 


$6.50 


ea. 


2/M2. 


I 


RED  OR  GREY  PLEXIGLAS  FOR   DIGITAL  BEZELS 
3"x6"x1/8"  95*  ea.    4/*3 


60  HZ, 


XTAL  TIME  BASE 
Will  enable 
Digital  Clock  Kits 
or  Clock-Calendar 

Kits  to  operate 
from  12V  DC. 
1,,x2"PC  Board 
Power  Req:  5-15VDC 
(2.5MA.TYP.) 
Easy  3  wire  hookup 
Accuracy;  ±  2PPM 
(Adjustable) 
Complete  Kit  *  age 

#TB-1 


SEE  THE  WORKS  Clock  Kit 
Clear  Ptexigias  Stand 


•6Big  .4"  digits 
*i2or24hr,  time 
•3  set  switches  (back) 
■Plug  transformer 
•aljparts  included 
Plexiglas  is 
Pre-cut&  drilled 
Size:6"Ht4V3"tWl3"D 

ASUPER  LOOKING 
CLOCK! 


Ih'tiiM 


Kit  #850-4  CP 


•23"  2/»45. 


6  Digit-LED  Clock-Calendar-Alarm  Kit 


•  12/24  HR  TIME  •  CHOICE  OF  DIGITS  *  28-30-31  DAY 
CALENDAR  •  AC  FAILURE/ BATTERY  BACK-UP  •  24  HR 
ALARM  - 10  Mm,  SNOOZE  •  ALTERNATES  TIME  [8  SEC]  AND 
DATE  [2  SEC]  OR  DISPLAYS  TIME  ONLY  AND  DATE  ON 
DEMAND  •  THIS  KIT  USES  THE  FANTASTIC  CT-7001  CHIP, 
FOR  THE  PERSON  THAT  WANTS  A  SUPER  CLOCK  KIT-TOO 
MANY  FEATURES  TO  LIST! 

#7001  B  [6  -  .4"  Digits/  Man-64 1  $39,95 

#7001C|4-  ,6"  Digits/2-. 3  T  Seconds]  $42.95 

ALL  KITS  ARE  COMPLETE  INCLUDING  IC  SOCKET, 
TRANSFORMER,    LINE  CORD,  SWITCHES,  etc. 

Cabinet  not  included  (Ideal  fit  in  Cabinet  I  above} 


W  DIGIT  CLOCK  KIT 


A  COMPLETE 

KIT  LESS  CABINET.  FEATURES:  MMS314  IC,  12/24  HR, 
SO/60  H2,  6-FND-503  LED'S.  PLUG-TRANSFORMER,  LINE 
CORD,  etc. 

[Ideal  Fit  in  Cabinet  II]  MOBS     9/*38 

Kit#5314-5.-.- ~„.«...... --...    "■'ea.    fc#    WM" 


JUMBO  DIGIT  CONVERSION  KIT 

Convert   small   digit    LED   clock    to    large    .5"   displays, Kit 

includes 6-. 5"  LED's. Multiplex  PC  Board  &  easy  hook-up  info, 

Kit  WJD-1CC  For  common  Cathode  $Q95       q/hq 

KittfJD-1CA  Forcommon  Anode  u  **       Z/    II 9. 


ea. 


DIODES 


IN4002 

IN  4003 
1N4005 
IN4007 

2.5A/1000PIV 

IN54O0 

1N914 

IN4148 


12/51,00 
12/  $1.00 
11/51,00 
10/51.00 

5/51.00 
5/ $1.00 
20/51,00 
20/51,00 


\ 


\\i 


TRANSISTOR 
SOCKET 

GOLD  PINS 

5/*1 .00 


SWITCHES 

ROCKER  SPDT  6/51 

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NPN 
NPN 
NPN 


TO-18 
TO-92 
TO-92 
TO-92 
TO-92 
TO-92 
TO-92 


Fairchild  Super  Digit 
FND-359 

.4"  Char.  Hi. 
7  jegmeflt  LED 
RED  Com.  Cath. 

Direct  pin 

replacement  for 

popular  FND-70 

95/  ea,  10/58.50 
100.S79.00 


SET  OF  6       FND-359 
WITH  MULTIPLEX 

PC  BOARD  $6.95 


25AMP   BRIDGE 
$1,95  ea. 

3/$5.00 

TOO  PI V 


TELEPHONE  FORMAT 
KEYBOARD 

BYChomerlcs 


2-t/4,Tx3fP 


^§5*       JUMBO  RED  LED's    Pkg.  of  SO      43 


95 


5/ 32"  thick 

$4.95 
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CLOCK  1CS 

CT-7001 7.95       CT-7002.. . . ,  1 3,95 

MM5314N...  3.95        MM5369N.,.+  2,50 
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IC  SOCKETS 

Pin 

Profile 

14 

LP 

16 

LP 

18 

LP 

24 

SP 

28 

SP 

40 

LP 

1-24 

$25 

,28 
.31 
.50 

,60 
.75 


SoiderTail 

25  TOO 

$  22  $.20 

,25  .23 

.28  .26 

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FN  0-359      RED 
FND-503      RED 
DL-33MMBREO 
DL-750  RED 

XAN-654      GREEN 
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If 


25' 

5' 
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1.35 

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95c 
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WE  PAY  ALL  SHIPPING  IN  CONTINENTAL  USA  -   OTHERS  ADD  5%  [10%    FOR  AIRMAIL) 


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12  or  24  HOUR  LED  CLOCK 

12  VOLT  AC  or  DC  POWERED  FOR  FIXED  OR  MOBILE  OPERATION. 


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BATTERY  BACK-UP 
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•  6  JUMBO        .4"  RED  LED'S  BEHIND  RED  FILTER  LENS  WITH  CHROME  RIM. 

•  SET  TIME  FROM  FRONT  VIA  HIDDEN  SWITCHES  •  12/24-Hr.  TIME  FORMAT 

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KIT  #2001  - 

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$    35 

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SO 

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1AJ00PIV 
1  A,  200  PI  V 
1  A,  600  PI  V 
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16 
18 
24 
28 
40 


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TO -92 
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T092 
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DL750 
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X  AN  -654 
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o«t.    WJtb    hpok&p    diAfnun,    Una    oa   itmporAtvr*    cou- 

tKilkf    too.   Wt,    2  Iba.      Cm.  No  13A23B2 

4*#*O«*«0***4*OOO*»**0O0***4*9++#**0»*+#+*0t*<*444*»**4**O 


oma 


^ 


]  2S  H,  2-^Bietcr  and  6-n»*t*f  imistar  rulio  oowfwton 
If  ju-ir  r±B  is  raobile.  aaanrL  tl  raiiLy  to  a  raot»W 
i«i»jrki..o*  fttstiow  and  rofttart  /w  Aania,,  aanv.  acAooi 
f»ct.krj.  TTtVlOO  tourb  toto  rormbr  kit.  Put  icrrladea 
njotntna  toueb  w«k*  pAd,  Motorola  Mri;f4lfl  rhip 
tritniwrt.  itiinon,  cntrr.  diASTOi-t,  nnj  G-IO  pr  Ixianl 
Klvctrlcal  ppecB;  12- IB  Tblta,  ft  nubi  4mu«,  4  v«jlti 
PC  wlfurt.       *  Lev*  1-MC  iryilal.    Cat.  No.      t,2A33Ef> 


Cat    Ho.  DcuHpKon  Sal* 

12A3149       TpulK  7di*  Pid       BA.BO 
12A3I3B2       MCl4410Ctilp        10. SO 


BUT  'EM  SEPARATELY 

12A33B3        P.C.  Boojw  2.95 


O0  000000O00QOOp00<IOO0OOOO0oe»ODOOODClOOO0OODOeO^0Q0O0C!00O 


o 

0 
3 

0 

D 

o 
15 
o 
o 

D 

a 

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o 

5 
o 

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o 
B 
9 

D 
CI 


,  .  4-dlf't.  0-5"  ttlptllB&I 
("IrjiK  .  LKIl,  built-in,  mu! 
nitfP,  witli  n  M>lo3SS  mitl- 

1  L-f  urn-thn  iileirrtt  chip, 
inou.ii  tn  rt  un  a  :i  %  1*^  x 
'•4"  nindulF.  Iliw"  *,U  tii-irK- 
Jiirv  di"Cr4t*  c^inponpnti 
nirtuiK^cl  iin  mtMlulf  hjf  tfEB« 

liiry,.       til       rru-jLJ-c       tfnli        H 

furiiiMiA  awltcbe*.  hrlikt- 
Ani  and  voltajff  divider 
Ctifiifol.  12-Lfi  roll  flla- 
ftiKRi  it-ini f Of m*r.  ACT  line 
r-4»nl  iintl  cur  Ifaltra  rul~ 
thiiU-in  olofst  and  radio 
nutpulr  iwitfh  fuik-imoi- 
floluuila.  5T«ati  iiamw  wp  la 
i  bamr.  foot  9*u  Saoat* 
«l4fm  diapiaar  (taJla  rou 
•rhaai     uom     nlarra     Irl*- 

Bjml,    Almrzm    dirplor     i  l*U» 

t*u   wbro   alsTRt   trixf*r«>. 


DIGITAL  CLOCK 


AUrta  dS_/<lFF.   IoatT4«|aai 
oiul  hookup  dxaxrarn*, 
IQIPC,  tat,  7  Oti- 


C*L  No, 
12A34 1 1 

MODULE 
WITH 

BUILT-IN 
"CHIP" 


$1495 


o 
a 
a 
0 
a 
a 

a 
— 

o 
o 
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0 

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a 


ooooq  a  a  ddqq^^o  0  ODOO  OOO^O  dbg  aaaooo0o46"00  bpoo  joooo  dqoqo  o  o 


ooo*4*oao+ 


■  LliM  CncMfat  MD1  HQM 


•  T  "LED"  tail  I 


,,'  Mod** 

~i  iniSnim  , 


KEYBOARD  X 
ENCODER  KIT 


Low«t    ptiev   Kajrhoard    and    EowAdcr    Ail   we*n 
Gowarai    mijpaaa:    ASClt     A*7*Jtiha;d     for    duta    terminal 
AppUrwtHMH-  Could  f  l»  T\',   UTTV.   C«W  TrzBA* 

miaaiat^  Aitair  ud  •■!(■»•?  ICLai  C6mpui±n,  ♦it.  Vi(1t«44 
2'1*>"  roDovvr  MtJS  snamury  allow ine.  cxkCudrd  ouiffUl* 
to  be  airfeWl  n^i  «>  *a?h  k*>"  Lt  dcpniMll,  C«w« 
dnuUaUAe  pr  b*ivrd.  &w*\timic  ablft  loch<  not  rwcAhJ- 
ral  on,  kcibuud^  Arninirf  nt,  nam  intfjral  Owoambli 
SOI  individual  **?  .  kribn.nl  ft]  k*r*  (49  ewcuded 
tn«'.  4  mode:  normal,  thifl  and  r<iOCfn|.  3  internal 
Janttiui  ksj-Ji-  shift  leach  *ld#  uf  bo«-d.  *tiifl  loch 
asd  eanuxtl.  ,1  fvnrlJ  "•  Kef  Br«ak.  Hrr*  la.  Itr^rai 
T  additioanl  fuiK't:  >A  b«  aaiifcned  by  uteri, 

Cai.Ho.      12A320B     K>frbo>rd  A  Encoder  Kit         tBB.Bft 
CM    Np,     12A320O     Hevbo«id   A  tnead**-  Wired      B&.ftS 


•  111  VAC! 

B  Cawtpactt 

•  LiEhtwtichtl 

•  Only  4    1I/1S' 
A  iyBw«e*pl 


"J- 


Rotron  Fans 


foflu  bj  kifiruu.  I'ihI  aALeJttttwly  fiii"  liL-ii  eqpt  be4-ao«e 
■if  liiu'-rirAl.  I'lMi^nduhtia  rnriiinjt,  ea  well  nc  rluithinp 
cncnputarOi  now**  ^ypnlSKs,  nfTir-e  e^ttlpmdnt,  IikIu 
prdjt  I'lnrtj   IfiintrfiiitiTB,   rnc ri v ■> r k  A   rutin1 1   Weighs  nnly 

i  Mi    i.iivv  ndisr;  uevkLi  iiuznuiii  -.   k    MKiimurv  »«■- 

Hint  ninlirr.  HrlVKK^IFJLK  A I  If  MOW!  Irnupilutn:*-  pm- 
".-.  l-rl,  RuUAble  fur  -4l>D  to    »  1'WP  F    Nmh    |  l  f,  VACH 

HZflft  rfim,    in  wim*,  .Ifi  nrnnn.  II imrl.  frunii'  rctani- 

ilm"    fi.  ils<  .irlniiLin  i  •    [iro|i^llur^    III    n    re  Inferred    phnno&Ec 

VeUturi     >i S ■  i ■  ■  U  .  H,,nn.nvpd,   trnm   n."<    .-.|-  il jini^rH      MimejF 

k  BitHrnnivf     1»2     lbs       12A310A  "I4u«ln"    3  bE-d» 


$69.95 
WIRED 

□  □ 

O&ubl* 

*ided      Outputs  ^tjndard 

PC  ASCII        7  biU      ; 

baard  plus  itrobr 

ificml  n-e-izs:  .  o3l*cr  req-ulrenwiiLA  jjIji  S  rvlte  and 
jwlnut  12  cedlA,  2fliUnfw.  arcMnr  ut  ptuiijvc-  Jnf,ie 
Output,    jumpej-   aelcciable»    <lurout    •'■nnertor.    On    ih* 

board  we  have  A    M  ^    Kn  hn.^Hli  1T.ST  FE\T>  RK 
7   LEDSI   Thew   L*ti>    djBpJor    ri«uall>   lb*  A>l   II 
rud*    tut    the    depreaaed    key.    TTt   ^«mpatibie,    KjI    in- 
cludaa      «^i     «*>-     kf>bratd.    |hr    bfiflrri.     ROM.     7    Li 
n^mluf*.  tfiamr-ilorpi,  TTL   [C'«  and   SOI  W# 

inrluii*-  ,iiiinnim  and  wirmj;  jri*truelo»ir  ftl)M  code,  Wt. 

7    Ibh.    SkM?   nVnrJ*ll:     1  JJ    l,   ft  i  B    \   2". 


FAIHCH1LD,  NATIONAL 
VOLTAGE  REGULATOR  PANIC 


YOUR 
CHOICE 

3  fur 
fl.TB 


SI: 


I     «Hr    MiTIPll, 

TO    lit   Of  IB    I   CASES 

PwSITIVC   DH  OtSCATIVE 


12 
IE 
:■ 

24 


Cat.  N**  I2A344S-  PaeJUv*  Vol  las*** 
Cat.  No.  12A1430  N«cativa  VaUaca** 


Stat*  n>ho|[a 
alyle  niue 


Twirfwi  Add  postAj;*     Hmtrd :  net  SO 
Phon.  :  Wnkefiftld,  Mltk  t^lTj  £4^3829 
R«Uih  16- IB  Del  CiTthiit*  SL.  WAkeA^ld, 

MINIMUM  ORDER $ft  |  IMtis  Pnsla^} 

POLY  PAKS 

P.O.  BOX  942 A  LYNNFIELD,  MASS.  01940 


I 


D  Send  for  FREE 
Fail  Winter  catalog 


r.rPoly  Paks  I  nc:V  Wakuficltl,  Mass.,  U.S.A.   1976 


196 


6  DIGIT  ELECTRONIC 
STCP  WATCHMT 


^10**?™**?™*™**™™*'**** 


LASER 


Poly  PakV  exclusive 


■liV    Ship. 
Wt,  b  an. 


LowoM  prices  anywh«rtl 
Spill  action  timing! 
Make*  mcchnnlcal 
stop  wntchfr*  obsolete  I 
Ittflftptrnanble  for  schools, 
Inba,   hpbE>yl^t«,   sporty 
mclng  f Hnsl 

%.      r  i     hrfufe    itfleffedl     RLAri,    ati]ll.h    llop,    FCEel    with   tin* 

hand,  PtituttJ  accuracy  of  .002  *t.  KfllUsate  di>*.i£Ti  •» 
liming"  won't  be  nccidaata.Ui  tn*i,  IiL»j»l|iV£>  MlXtTE-S, 
5BCOXDS,  TENTHS  ami  IK  NUREDTHS  of  set  end*,  up 
K»  it)  mujiti,  5*  By  ••eoada,  firictit  tCR  dt*pf*> 
SpLt  «c1iou  allow  i  freeiing  p*itita!  ri*ns  time,  Ifeea 
feed  mi  elapr-cd  lima  *iTirf.  fLrtl  r  +  Ndinp:  <  iJlowt  tLtFinjt 
3  at  niufe  pKf!icipAHL«  in  ifc*  •  aiMr  avaail  .  Built  .-m  ja.eE 
fwr  r«3?te  oo-ofl.  C**e  mid*  +/I  hi. Impact  pluilr,  da* 
■  i«n*d  to  fit  moth'  '»  band  Thumb  cfart*  and  iloiM, 
nUddJ*  6n«;=i  rtifiU,  ifiilii  r  octroi  a  «pin  Has  hat: 
cbaralaa:  lack-  EAST  TO  Ml  PIJ<!  CaaBpaalc  wttH  *teb- 
br-alep  taatroctioaa  s.i.  «*  ,  a  I*;  I  l*A",  Caai  aa 
Wfiffrt  MCAB  hait**!**  h  •*»  ott  C»i    NV  02CU149 

wi    »  oi*.  c«t.  n*.  ioaisos  kii  ^j  rt(-v 


II 


O-LiTE" 
DIODES 


^»W#Mff  *p*»»##e»  a*  *»#*■*■  *■«**■*'■ 


St. 95 

Cat,  No.  12*1497 


HI-POWER  NPH 

TRANSISTOR 

Tjfp*    TO- 9    nfttilar  to   RCA 
Raled     #>      l&O    walla.    30 
itnpi,    SO    io    1  tO   tmo,    up 
io    «D    HTK     Superced***    th* 
JtWiflGO.  Silicon    IN  17 71 


ii 

l 
i 
i 
i 

i 


s^vtcr   beforf  opfrrem 

(m  far   fib  wa  know  J  F  Type 
LAH[k&9.   With   power   rat- 
ine; of  fi   io  9  watt*,   truji*- 
milling    a    powerful    ray    of 
infra  raid  Ijjrht    Designed   in 
ha'.ar  injunction.  fin!«l  !£©• 
*r.tuir'Mtv,         N-Tn>e.        TO 
P11_SK"    m&A-v     np-arali^n, 
*Va^  elemrLh      appra2L-BQ  la- 
la  ,   jl   *olla  tititm   roita*T*r 
tareah'jjd  t-ttrrrftj    10,  naTt- 
|Ua«    arta    1    a    .08.    Max- 
peak   f*d    C-xreni   40     YOU 
Mt  ST ■imitty  THE  LAEEJt 
SAFETY    RULE    aecW=£u)- 
ka«    Uaar    diode.     Cold    *s. 
23*  diameter. 


turns 


100"  S  OF  BARRELS  PURCHASED 

For  the  first  time  .my where.  Poly  Pah 
merchandiser*  introduce  a  new  way 
in  buying  the  economical  way.  Raw 
stock  from  the  "barrel".  Remember 
the  "good  ole  day*"?  They're  back 
again.  The  timi  way  merchandisers 

throughout  the  United  States  buy 
from  various  factor  I  m%  .  .  .  their  over- 
runs in  barrels.  Poly  Pah  has  done 
the  same.  Therefor*  you  are  Retting 
the  umi  type  of  material  as  the 
RE  TESTERS  DO! 

1 1  ST  'EM  YOURSELF  N  SAVE1 


Buy  10 

BARREL  KITS 

JFree 


YOUR 
CHOI  CI 


ANY 
KIT 


Htr 


-I SN74O0   DIP 

Cet-Saw  1 2A24  IS ,  tMt*» 


!£*    ^f* 


KIT 


TS  iaw 

Sl»l 


jl— LINEAR  OP  AMPS 


71  for 
11.11 


.1 IN414J/I14 

C^H012H4il: 


DIODES 


•4 "4OO0"  RECTtFII 

Cftr«»liA24  1  7,urrt*ll*d 

-T VOLUME  CONTROLS 

Cat.  M<vl2A242t.  lOO  %j * 


# 


100 

I* 


for 
•  S 


n 


I* 5UBMINI  IF  XFMftS 

Cat. If  =k  12A2422,  IdO  %  s^ri 


J1JM  OVEM  ENTl  SET  OF  I 

LEFT  A  RIGHT  CHANNEL 
BALANCING  METERS 


Tkka  aat  W?  aaatan  aaad  ia 

batleataa  0  (e 

■itrcirr*  iw 

tt|    uH   tk»  oi*«f    "LEFT"     far  tali   ehaaa«i.    l*.a 
**-«  tkru   ptaatie   cui     For  ura^ltioa  balanced 
■■-■-"»'  Wt,   ■*  •**■  Cai.  Wa.      124*133 


It  d» 


ti 


I 

i 


D 


•  Mad* 
for  RCA 


: 

: 

: 
?the  purifier: 


JTl  1 POWER  TAB  TRANS 

Cat  .Ho.  12A242S.untaitad»npn 

fil POWER  TAB  TRANS 

Cat  N«12A242Aluntaat<id.pnp 


15^ 

*  c%.°^  D 


40 
SI 


for 

■  ft 


100  for 
SI,  93 


40  far 
SI 


^^55" 


4  0  for 

11.31 


J  14 PRECISION  RESISTORS 
jl.ttft,12AJ42arfnirlca0.nn  m*irh 


2  00  for 


10.7  mH2 


"15—IWOS  FET  TRANSISTORSf^Z  «<■  for 

Caj.fip  13^3439 _    JiLA $1,04 

Si*  —  0IPPEO  Mf I. A R9 


e 


£tO LONG  LEAD 

Cat  «U.i2A25»», 


t  CERAMIC  FILTER 

I    --S3  $1.98: 

J   ^TTK     ItAMA     *      AUDIO-} 
a  FM  tLCS'    SfcatpEn    ap    yw  a 

natter  na  or  hwm  art-  *       rf» — NEON  LAMPS 


EAD  DISCS— fO 

lW%|*tl       ^L*? 


150  for 
Jl.SS 


33  AIWF  BRIO  CIS 
By     top     US     mahtr,     t-liui 
type    l*ad>.    4    a*. 
Cat.  *ta     taazsri 


G 


PHY 
SO 

too 

20C 
400 

too 
eoo 


3AL3 
3i  *i 
l.aa 
a  aa 

no 

4.2  ft 
4.11 


lean.    Offer*    unbeatable 
J  J»*ic-i*j   and   santitivitT     la  J 

*  4    inial    ibicMed    *»av    ooi^O 

*  *    a    syifl    a    7/1*-.    Nu* 

*  tuniAdr  needed,  Frachxinn  • 
X  hiadaaaa  Alien  acll  for  IT,  X 

*  84**  »M*nr  fit.  Similar ♦ 
#unK>  h*k#  a  db  bazHtwtdllte 
*■(  .Mft  kfli,  SO  db  baitd-X 
I  width:  7 DO  kllr.  Hipp'*-  >t 
#-1v,  litipidajicc  '  1O0-!Kyn# 
a  ohmv,  Wi,  J  fla.  • 
*C»t.   H«.       1241467  * 

t***ttt4t4*tt*t**tttf« 


*2  4 PLASTIC  TRANSISTORS^     lOO  for 

Cit  *l*.  12*2404. ntrt»*t^f ^^3^P  51.00 

-'10  —  PRE-FORME  D  RE  St  STQRSiJ  2  50  for 
cnM«i2*JWJ.iw*Vi**Hi  aaTJJJl  |        si,aO 

3  0  for 
31,30 


Cat  N*  12A2«ia,lM-.t.*4 


-17-^l^AMP  BULLET  REC 
Cat  ha.12A2«lSTM*****t*d 

:i| 2N30SS  THAHSISTO  RS^ 


G 


M9 Hi    POWER  PNP  TRANS 

Cat  **  i2*2«l«,l<i0^a«iKi  « 


is  for 

ii*> 

20  for 


£01 JUMBO 

C4t-AI*il2*i72l 


RESISTOR 


PAR 


100  pe- 
ll.34 


* 
■ 
* 


HV   1014 
NI-POWIR 


n 

ttD 


ILluenLnalei    Vi"  ill*,  clrel*" 
HiHRleiLBUy    for  uan«l   mlr 

iliaftLE-tr.       Hq.       12A14BT 


15  for 
$1.98 


* 


tlltflllllllllllllllllltl 


5GS-ATES  4  WATT* 
AUDIO  AMP 

3  for  S2.S0  r"3JM 


?54         S   DIGIT  READOUTS 
Cat. ho  114  2732  ck^ 

ISO SLIDE  SWITCHES  V 

Cpl,NpPi2A27lB,laO*A  Rand 


\A 


TfS*  |  1  7  tor 
11.04 


3D  for 
11-11 


ftaalf  cftlt  rat«4 
■LiaW4   <-aa  baadt# 


4  wwttJi. 
Tmiim.  avadnr 


That*  riatitT  0STT  noLLAlt! 

that     jwrf.!»»rly    bckt 

141  th*tr  type  aambai  TAAi«tll 

I  I  :  4  atom  tap  \  4  nr-ut 
lufi.  H»«ir  *prci.  aatf-eaa t«rMt4  ewaa,  tew  i(ai*i>(rfcr 
carleul  fiuTtat  2.ft  puI*  Aar  aapplr  T*ltaa*  trasm  «  ft* 
k«T  IS  traataiator  rtmirtrr  Daraei  cvvpled  iznrot.  htf> 
faaui  awaadaa**.  Voliaea  »*m  72  de  Ovtuut  laaiaai 
ISO  a4U    With  ^p*ht*  A  frplral  applwratlntt*.  3\  1  Ot 


Dfaa,,  dqi^  *itb  tavtal 
***»,    low 


100 

MICROAMP 
PANEL  $3.50 

METER!  3  Par  00- 

Rectaoaiitar  " C  tbxv  blaa* 
lb?  raa*.  face  has  aw  AdSK 
bera,  l"»e  fur  taaaJas;  1*^*1, 
TUP  f»-!inrtar.  fin  »#  I14KT, 
«4.  Stat  I1:  »  T,  >  1T*", 
Wt.     1     «.  Cat.  H«,  12434*4 


S9mI POLYSTYRENE  CAP 

OT  ^.1  242723. 10a%4<»d 

m  —  MIXED  READOUTS 

Cki  No. J  24  Z7  3i. u*)Ui tad 

rfS4 3  WAITERS- 

Cat- Ho.  1 2  A3T3  S ,  lOO  %  aaaa 

;T1 CAPACfTOR  5PECIAL 

Cat  ***   l2427  3B,IOO  ".Kim! 


100  for 

11-11 


100  for 
11,33 


***fR4*f*fReV#**f34**f»J 

HIGH  AMPERAGE 

ENERGY  POWER  PAKS 

Mii«t  var^iiljlp  rhpricy  bai- 
\tr>    ii^-wfr  i ■  ,k h   wa'ra  aean. 

lampiaa     SO    4kmpi     <*     3 

vii|i»,     fjtmff     "nnt     fict     n 
ki»n)i*   of    vr^mcT'1    and   cur- 

i'i-iii       i - 1 1 ] i ii r* 1 1 L 1 1 n h      for 

vntrriuiiry  lauppELve.  und 
oIHht  run'  '*r  ureoa  ran"iri 
in  if  nnWi  n  ilcvLrr.  Lata  rlec- 
Irolyl*  Ik*  3  ctilnir  halli 
abowifU      i»rrip*?r     lave]      of 

3  VDC    &    20  Ampt  *"Irf'M  "' ^  '  ■' 

M»d«  ay  Wills rd 

Tyj**  3  0-3 


;T1 TRANSISTOR  ELECTRO 

Cut  N*.  12*  2747 


274 1  WATT  ZENERS 

Cat.  Ha ,  1 3427  4 1 .  w*ita  ft  *4 

?41 — LMS40T  VOLT  R 

/■* HOBBY  LCDS 

C«I  No  13A2353.«>taatad 


«5*5 


for  S  10 


j-47 NATIONAL  IC  BONANZA 

124  J£BO,uaLe*l**d 


$1-50 


a 


wvii.nti-f-    "e      n^i- 


cat 
tPaf%FliaFafa1lfRjFWlJ3l 


v"     Wr     r,   Jbi,   Ptaaiic 
Uiru  hpAiT-iliitj-  rpM, 
Ra.       J3A1133 


itsoaa> 

Tho ."iSAWSD 
■'""'Ji.^oi.rjlh^ 


arff- 
-   de-ei"1*3 : 


By  force  U.S.  mafciarl 

4  Jumbo  0-A    LED  d»4ltal 
B-e-e-4-e-r  ulirm! 

Flmhlne;  second*! 
Minimum  of  p*rf«! 


$29 


Cal,  Ha. 
124 1449 


BIG  B1NG  BEEPER*  DIGITAL  ALARM  CLOCK  KIT 


"\.  .*r  b«fi>^e  o4«rt4-  Sa*a»  b*>fer«  in  bit  foroat  l»'.S. 
tnidveft  fiur-^ry  faarrr  C40't  ftatna  It)  lay;  "it  i*  iq 
txi(»ui-*r  viirrfL  *>^f  HCrt  km**  a  kd  n?  lir  J»<jbb* 
iiiArn.l?  '  WE  AGREE!  Wired,  ibt  «Uia*«t«<d  Ml  pr*C* 
bjr  Iba  vrlRiiiiaJ  faJ.-.L.rr  t**  l&»  drfartrntjat  itatea  wu 
143.0  5,,  B*?4iiiifuJly  deaif/nvd.  atli^tflive  enitua;h  fur 
any  hum*,  room,  cFFica.  Alt  cmntruli  in  from,  niakai 
vmiuitArr  control  eaay.  Fcaturai:  3  k  nVz"  w|da  alopad 
ttinjilticiir /beijee  face.    L'a**    fainauji  all    LED    0.49" 


ir  all*.  HoaleA  50150  "cluck  c*np'  ,  with  built-in 
brvper  «]arm  crrcultrT.  Froa*  paaal  ctrfltrols.  OJ»-OFf* 
ALARV,  bour  sel,  1 0  frtlauie  aat,  hold,  alarai  ■*?? 
butluos  flaaliias  aacoada  talOB,  »tth  ■traakrr.  *iudi' 
hi*  berprr  atarca.  tocludaa  backup  po**r  fallnrv  f*»- 
iw*,  24-bour  ■larnt.  114TAC  HO  h*  powar  auppEr. 
Ufiwia  f*jalkir*i  fur  eitra  alaap.  Fur  1st  ftrat  time  th* 
ti(*brat  QU«Jitj  fAcliir>  produft  at  towP  to^  prices  and 
WOW  IN  KIT  FORM    Wt.    3   [fai.Eamy  to  build! 


-•a. 


100  for 

11.00 


#••— LJTRONICS  LED  READOUT] 

C  at.  N  el  2  A3  tetrad  mixed 

.-•1 SILVER  MICAS 

C*1.Na   124  JO  16. varl*.  try 


lujjD  io 

****      lOO 


for 

so 


11.30 


;»a — 1  AMP  EPOXY 

C mi.  Hit.  1 34  J 204, uttterted 


100  far 
11.04 


731 HALF  WAITERS 

C**.H<k.  124  104«.  IOD'i  fiaod 


too 
11 


for 
,00 


210 PHOTO  ELECTRIC  CELLS 

Cp4.Ko.L2A1D32i100  '■Vgaod 

:i04 SLIDE  VOL  CONTROLS 


"N 


a 


Cat. Wo.  13A3057. 100  ft  ffiod 


s too TERMINAL  5TRIP<= 

C*t,h:<i.l2AJL3€,wliJa  aaat 


&t 


10  for 

11.33 

10  for 
11.00 


J^lttoA 


O 


no  for 

11.31 


£110— S OPPRESSOR  DIODES 

Ca  t.  N  o .  1 2 A  2 1 37  ,u  nteatad 

fflil MICRO  MINI  LEDS 

Cat.No.l243l2«,varialy  -^ 

ft  11 MOLEM  SOCKETS' 

C  » I  *f  o    124  11 44, 1 OO  r*  4«i  d 


so  for 
Si. 11 


u 


40  for 
■  1-11 


D 


200  for 
11,11 


JT1L3 PREClSfON   RESISTORS  100 

Cai.Hp.134  JJOS^OO^f^^^^^aa^aTEj-^1-   SI 

rl  21 MINI  MAGNETS    A 

Cat  No.  1 2 Alt «3 


for 

,40 


#110 UPRIGHT  E 

Cat  N*»_ 1 34  1 2 2 S .  1 OO  T* 

;ilT AXIAL  ELECT 

CilNi    I  2 4  J  2 2 7  . a M - 


LECTROSy^ 


too  for 

11.30 


4  3  for 
11.00 


fill — -MINI 


DIP  IC'S 


40 
11 


far 


21  SO CRYSTALS 

Cal_hfr.l  34  l23D,t**ai*ir  la  Ark 


71  for 
11.30 

13  for 
11.10 


ELECTROS 


.1  11 — .TANTALUM 
C  el .  Wa.  1 2  All  ■  S,aa|  jc*d 

fill CMOS  IC*S 

CatNq.taaJ3A7runtQ»t>d 

.'111 PANEL  SWITCHES 

Cai.Hu   i  2  A  (26S.by  Oak 


INDICAT 
ay  type* 


-140 LAMPS, 

Cat.Re.l2A3237rnw 

J?*41 10  WATT  ZENE 

Cat,No,i?A320a,K(Md  yield 


it* 


Ll 


f  144 RCA  PHONO  PLUGS 

Cat.Ha.lJ4  33B3T100r»gaft4 

£140 ROC KER  S WITCHES 

CbI.Ho.  1241302 


V>_1  is 


AO  for 
11.34 

for 
04 


D 


4©  for 
SI. 00 


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£1S| MAGNIFIED  MAN 

G.I.«o-12»3WS Jen*  ra tec fs 


25 
11 


far 
00 


SO-gaja,  T 


1Z  for 

01.04 


;t5»  —  MODULAR  SWITCHES 

Cat  Ho .  i  J4JlM>.Ceatraleb        .  ^*-"' 


-140 LMSOOKC  V. 

Cm  l  N  e .  1  2 A 1 1  JO  ,u 


REG 


;U1 — PLASTIC  TRANSISTORS 
Cat  Ho.  1243343. 1 00  "V  mat.Hal 


210S MINI  TRIMROTS 

Cat-Na.  174 134 5. for  p  <. 


3# 


£172 31  AMP  SCRS 

Cat-  N  *..  1 24  J393 , 1  OO  "V  a*at*»  la  I 

£171 31  AMPTRIACS 

Cat,  Ho.  1 2  A  33  SCT 1  OO  *h  naetarljit 


_s!V 


3  5  for 
VI  98 
3  0  for 
11^00 

1- 
11 


3  -pea. 
11.00 


PRECISION  POTSI 

fa] r child:     -Ema-tt     **THK  GREY 

IMCH"* 


I  . 


■4  lima  ;iB/tfli  3/lfi'. 
Featuraa  31  turn*.  Uneaj. 
4i  mil  v  Io  Mniifaea  22ntP. 
ft  ^  tolerance.  1  wa.tt, 
irvmifl   gray  In  color.  With 

h    St'.i\rl    ytftttd    Icada,    Hmnw 

drK'or   adjuat. 
0M.  Nt*.      12  A  3430 
Ohm  a  Ohm*  Q       lOK 

D     IB       D    S0O       □   20K 
U     30       lj       »*        d     334 
1  lOO  2  QK  aOK 

D2SK 

a    in 


J  30O 


lOOK 


'Tasf  Charge"  $1.69 
^  NICADS  //r* 

M<m4   roajinioaJr   ased   ntrad 

baiurr:  l.tvtH-  sno  mila. 

Faat  i  iaia,i  aady  reqairea 
%  Kntira.  ntbers  13  Io  24 
is  :-^i*    cat  «o.      1 2.434 ii 


MEMORIES! 

8008 ...$T4,95 


310T-1.,„, 

2102 

5H0M 

2102-2 

2111* 

2112 

1101 

1103 

1702A 

nfl  n/l  5  204 
MM5260 
MM  526  2 
MM52H3Q 
MMS202Q 


|rtl*""^^l^i *■■  .^w  — v-i, 


1.95 
1.50 
1.95 
2.25 
3,50 
3,50 
.88 
100 
8,88 
11.  SO 
1,00 
1,95 
8.8S 
5.95 


Tartm:  Add  po^taev     Rated :  nrt  30 
Phono  i  Wakefield.  M**»,  C€H>  245-38^9 
Ratal  I:  H5-1S  Del  Caiminr  St..  Wolrrfield. 
MINIMUM  ORDER  —  16. OO 

POLY  PAKS 

P.O.  BOX  942 A  LYNNFIELP,  MASS*  01940 


QPoly  Paki  I  nc"  W.ikflf  irldF  Mais,,  U.S.A.   107C 


197 


S.D.  SALES  CO. 


P.O.  BOX  28810- 
DALLAS,  TEXAS  75228 


Stick  It! 

m  YOUR  CLOCK, 
IN  YOUR  DVM.  etc. 


HUGE  SPECIAL  PURCHASE! 

NOT  FACTORY  SECONDS 

AS  SOLD  BY  OTHERS. 


4  JUMBO  ,50  IN.  DIGITS 

ON  ONE  "STICK"! 

(With  Galons  and  AM-PM  Indicator) 


$3.95 

BUY  3  for  $10.00 


BOWMAR 
4  DIGIT  LED  READOUT  ARRAY 
The  Bowmar  Opto  Stick.  The  best  readout  bargain 
we  have  ever  offered.  Has  four  common  cathode 
jumbo  digits  with  all  segments  and  cathodes  brought 
out.  Increased  versatility  since  any  of  the  digits  may 
be  used  independently  to  fit  your  applications. 
Perfect  for  any  clock  chip,  especially  direct  drive 
units  like  50380  or 7010,  Also  use  in  freq.  counters, 
DVIVTs,  etc.  For  12  or  24  hour  format. 


1024  BIT  RAM's-        590 

8  for  $4.00 

Prime  1103  1K  dynamic  RAM's.  Organized  1024  x  1. 
Packaged  in  expensive  military  quality  18  pin  ceramic 
DIP's  with  gold  plated  pins.  300  NS.  Typical  access 
time.  For  either  the  computer  hobbyist  or  profes- 
sional this  is  the  best  RAM  buy  anywhere!  With  spec, 
sheet.  Originally  cost  a  computer  mfg,  over  S3,  each! 
At  this  price  —  sold  on  a  first  come  first  served  basis. 


HOUSE  NUMBERED  TTL  IC's 

7408  -  8/S1.  PLEASE  SPECIFY  THAT  7438 

7420  -  8/S1.  YOU  ARE  ORDERING  74141 

7417 -5/81.  HOUSE  MO.  TTL  „ 


5/S1 
3/S1 
3/S1 


VOICE  ACTIVATED  SWITCH 


$1.49 


PANEL  METER 
FOR  DC  POWER  SUPPLIES 


$2.95 


F.S.  =  1  MA.  DUAL  SCALE;  0-30V,  1-1.5  A. 


PRICE  CUT  ON  LOW  POWER  2102 
21  L02-1 .  Low  Power,  500  NS.  Static  Ram 

8  for  $12.95 


MOTOROLA  SCR 
2N4443-8AMP  400  PIV 


P.C.  LEADS 


2  for  $1.00 


MINI  AUDIO  AMPLIFIER 


$1.49 


Has  mike  that  drives  a  transistor  amp.  that  turns  on  a  SCR. 
Perfect  for  experimenters. 


3  Transistor  amplifier.  Originally  used  in  mini  phonograph, 
Perfect  for  the  experimenter. 


MINI  ALARM  BELL 


$1.49 


Works  on  1%VDC.  Perfect  for  all  kinds  of  alarm  applications, 
etc.  A  perfect  bell  for  the  "whistle  and  bell"  section  of  your 
ALTAI R  or  IMSAL 


8080  A 

8008-1 

8212 

8224 

8820 

8830 

8838 

MC1488 

MCI  489 

2513 

MM5204 


MICROPROCESSORS  AND  THINGS 

By  AMD.  Outperforms  INTEL 

High  Speed  8008 

I/O  PORT 

Clock  Generator 

Dual  Line  RCVR 

Dual  Line  Driver 

Quad  Bus  Transceiver 

RS232  to  TTL 

TTL  to  RS232 

Character  Gen. 

4K  E  Prom 


824,00 

12.50 

3,50 

4.95 

1.75 

1.75 

2.00 

1.50 

1,50 

10.00 

12.00 


Axial  Lead. 


FILTER  CAPACITOR 

8000  MFD,  15WVDC. 

95c  each  Computer  Grade! 

Limited  Quantity 


ESPECIALLY  REQUESTED  TTL 

74LS00  -  49c      74132  -  $1.70 

74LS04  -  49c    74S138  -  $1 .95 

7416 -49c 


12  VDC  VOLTAGE  REGULATOR 
7812  -  TO-220  -  RATED  1  AMP. 


990 


HEATSINKS  FOR  VOLTAGE  REGULATORS 

Black  anodized  aluminum  "U"  Shaped.  FitsTO-220  case. 

4  for  $1 .00 


FAIRCHILD  RTL 

The  most  popular  digital    IC's  ever  produced.  Very  hard  to 
find. 

UL914  DUAL  2  INPUT  NOR  99c 

UL  923  JK  FLIP  FLOP  $1.19 

ALL  IN  TO-5    8  LEAD  PLASTIC  CASE. 


198 


S.  D.  SALES  Co. 


P.O.  BOX  28810-  A    •     DALLAS,  TEXAS  75228 


4K  LOW  POWER  RAM  BOARD  KIT 


imsai  and  Altair  8080  plug  in  compatible.  Uses  low  power  static 
21L02-1  500  ns<  RAM's,  which  are  included.  Fully  buffered, 
drastically  reduced  power  consumption,  on  board  regulated,  all 
sockets  and  parts  included.    Premium  quality  plated  thru  PC  Board. 


THE  WHOLE  WORKS 


$89.95 


a 


n 


4  1 


8  Digit    LED 
METRIC  MASTER 

$19.95 


RAPID  MAN  -  12" 

$29.95 


$1,000,000  CALCULATOR  PURCHASE! 
We  bought  the  entire  stock  of  a  major  manufacturer.   New,  guaranteed  units. 

Five  functions  PLUS  complete  Metric  Conversion  functions.     Re- 
chargeable  batteries.      Small,   hand    held   size*     With  AC  charger. 

12  Digit  -   Desk  Top  Style.    Sturdy  design.    With  memory  and  four 
complete  functions.   Big,  bright  display. 


ALARM  CLOCK  KIT  SIX  DIGIT  LED 

Thousands  of  hobbyists  have  bought  and  built  our  original  clock 
kit  and  were  completely  satisfied.  But  we  have  received  many 
requests  for  an  alarm  clock  kit  with  the  same  value  and  auauty 
that  you  have  come  to  expect  from  S.  Q«  So,  here  It  ts! 
THE  KrT  INCLUDES: 

1  Mostek  50252  Alarm  Clock  Chip 

6     Hewlett  Packard  ,30  In.  common  cathode  readouts 
15  NPN  Driver  Transistors 

2  Switches  for  time  soL 

2     Slide  Switches  for  alarm  set  and  enable 

1      Filter  Cap 

4      IN4002  Rectifiers 

1      IN914  Diode 

1      .Gl  Disc  Cap 

15   Resistors 

1     Speaker  for  alarm  PC  B— $3.00 

1     LED  lamp  for  PM  indicator  XFMR-  Sl.50 


$9.95 


Brand  new 
of  projects. 
MC724P  —  59C 
MC725P  —  59c 
MC764P  — 49c 
MC7G7P  —  69c 
MC  7  7  IP  —  49c 
MC775P  —  S9c 


MOTOROLA  RTL  IC'S 

factory  prime.     Hard  to  find,,  but  still  used  in  a  variety 
(See  the  RTL  Cookbook  by  Howard  W,  Sams.) 

MC780P  — S9C  MC791P— 69c 

MC792P  -  59c 


MC785P—  49c 
MC7B7P—  fl9c 
MC788P  —  49C 
MC789P—  59c 
MC790P  —  89c 


MC799P—  59c 

MC970P  —  89C 

MC9709P  -  69c 

MC9760P        69c 


$5.95 


60  HZ  CRYSTAL  TIME  BASE  - 

FOR  DIGITAL  CLOCKS 
S.  D.  SALES  EXCLUSt  v*E* 
KIT  FEATURES; 

A.  60  hz  output  with  accuracy  comparable  to  a  digital  watch 

B.  Directly  interfaces  with  all  MOS  Clock  chips 

C.  Super        low        power        consumption         (1.5        Ma 

D.  Uses  latest  MOS  17  stage  divider  IC 

E.  Eliminates  forever  the  problem  of  AC  line  glitches 

F.  Perfect    for   cars,   boats,   campers,    or  even    for   portable   clocks 
at  ham  field  days.  BUY  TWO  FOR  $  10.00! 

Q.  Small  size,  can  be  used  in  existing  enclosures, 

KIT  INCLUDES  CRYSTAL,  DIVIDER    IC.   PC  BOARD  PLUS  ALL 
OTHER  NECESSARY  PARTS  AND  SPECS. 


tYP-} 


7400  — 
7402  - 
74L04 
74504 
7404  — 
7406  — 
7408  — 

7410  — 

7411  — 
7413  — 
7420  — 


19c 
■  19c 

-  29c 

—  44c 
19c 
29c 
19c 
19c 
29c 
50c 
19c 


TTL 

7430 
7432 
7437 
743a 
7440 
7447 

7448 
74SI 
7453 
7473 
7474 
7575 


I  NT  EG 

—  19c 

-  34c 

-  39c 

—  39c 

—  19c 
-85c 

-85c 

—  19c 

-  19c 
-39c 

-35c 

-  35c 


RATED  C 

7476  - 
7480- 
7483  - 
7485  - 
7566 
7490- 
7492  - 

7495  - 

7496  - 
74121 
74123 
74141 


IRCUITS 

-  35c 
-49c 

-  95c 
-95c 

-  45c 

-  65c 

-  7Sc 

-  75c 
89c 

-  38c 

-  65c 

-  75c 


74153 
742  54 
74157 
74161 
74164 
74165 
74174 
74131 
74191 
74192 
74193 
74195 


75c 
LOO 

75c 

95C 
1,10 
1.10 

95c 
2,50 
1.25 
1.25 
1,00 

69c 


r* 


CUBO'      -DIGITAL  ALARM  CLOCK  CUBE 

A  PERFECT  GIFT  -  NOT  A  KIT! 
The    CUBO    Alarm    Clock    mfgT    by    Corvus,    division    of 
MOSTEK  CORP.     Originally  sold   for  $49.95.    We  bought 
out    their    entire    Inventory,      All    new,   individually   gift 
boxed.      Mini    size   (2VV    cube}    with  maxl   performance. 

FEATU  RES- 
4  Digit  HLP.  Bright  Display  $14.95 

"Second  Hand*'  LED  Activity  Indicator  PAfH 

24  Hour  Alarm;  J2  hour  real  time  format 
10  Minute  Snooze 
Auto    Display   Dimming   — 
AM/PM  Indicator 
Power  Failure  Indicator 


% 


1000  MFD  FILTER  CAPS 
Rated    35   WVDC,      Upright  style 
with    P.    C.    leads.      Most  popular 
value    for    hobbyists.       Compare 
at    up    to   $1,19   each    from    fran- 
chise type  electronic  parts  stores. 

S.D.  SPECIAL  4  for  $1. 


A. 
bJ. 
C. 

a 

E. 
F. 
G, 


(Add  75c  P&H  I 
Adjusts  to  Ambient  Light 


Uses  Famous  Mostek  MKS0250  MOS  LSI  IC 


MOTOROLA  POWER  DARLINGTON 

Back  in  Slock! 
Like    MJ3001.        NPN     S0V.      10A.         HFE 
6000  TYP.     TO— 3  case.    We  include  a  free 
723  C   volt   reg.  witrt  schematic  for  power 

*«Pply  SPECIAL  -  $1.99 


FAIRCHJLD  BIG  LEO  READOUTS 
A  big  ,50  inch  easy  to  read  character.  Now 
available  in  either  common  anode  or  com- 
mon cathode.  Take  your  pick.  Super  low 
current  drain,  only  5  MA  per  segment  typ- 
Icar.  YOUR  CHOICE:   6  for  S7 .50 

FND-510       Common  Anode       $1.50  ea. 
FND-503      Common  Cathode     $1.50  ea. 


WESTERN  DIGITAL  UART 

No.  TR1602B.    40  pin  DIP. 
This  is  a  very  powerful  and  popular  part, 

NEW  -  S6.95  with  data 

LIMITED  QUANTITY 


MICROPROCESSORS  &  THINGS 
By  AMD 

80S0A           Better  than  Intel  $24,00 

8008-1        High  Speed  8008  12.50 

8212                  1/0  Port  3.50 

8224          Clock  Generator  4.95 

2513      Character  Generator  10.00 


SLIDE  SWITCH  ASSORTMENT 
Our  best  seller,  includes  mini- 
lure  and  standard  sizes,  single  and 
multi-position  units.  All  new 
first  quality,  name  brand 
Try  one  package  and  you'll  re- 
order more.     SPECIAL  -  12/S1. 


RESISTOR  ASSORTMENT      />*^ 
r4   w   5^     and  PC    leads.        ^K. 


A  good  mix  of  values. 


20O/S2 


745200 

256  Bit  High  Speed  RAM 

Same  as  32516 

$3.95 


IK  PROM  BACK  IN  STOCK  * 

S2S129.    256X4.    Bipolar,  50  NS. 

FAST.    WITH  SPECS. 


$3,95 


8T97B 

Hex  Tri-State  Buffer,    Back  in  stock. 


UP  YOUR  COMPUTER! 

21L02-1  1K  LOW  POWER  500  NS  STATIC  BAM 

TIME  IS  OF  THE  ESSENCE 
And  so  is  power.     Not  only  are  our  RAM's  faster  than  a  speeding  bullet  but  they 
are  now  very  low  power.    We  are  pleased  to  offer  prime  new  21L02  —  1  low  power 
and  super  fast  RAM's,    Allows  you  to  STRETCH  your  power  supply  farther  and  at 
the  same  time  keep  the  watt  light  off.  3  FOR  $17.50 


SALE  ON  CUT  LEAD  SEMICONDUCTORS 
Leads  were  cut  for  PCB  insertion.  Still  very 
useable.     AH   new,  unused.     Some  House  no. 

lN914/ln414B 100/S2. 

1N4002  1  Amp  100  PlV .  .40/S1, 

1N4745A  16V  1W  Zen«tt  .,,..,-  .20/%  1. 

EN2222  NPN  Transistor ,2V$l- 

EN2907  PNP  Transistor 25/S1. 

2N3904NPN  Driver  Xstr 25/S1. 

2N3392  GE  Rrfr-amO  Xstr 25/S1- 

C103Y  SCR,  S00MA  60V 10/Sl. 


C&K  MINI  TOGGLE  SWITCH 
No,    7103    SUB    MINI    SPOT    Center  OFF, 

SPECIAL  -99c 


TERMS: 
Money  Back  Guarantee,     No  COD.     Texas 
Residents  add  5%  tax.    Add  5%  of  order  for 
postage  and    handling.      Orders  under  $10. 
add  75c.    Foreign  orders:    US  Funds  ONLY! 


$1.25 


CALL  YOUR  BANK  AMERfCARO  OR 
MASTER  CHARGE  ORDER  IN  Oft*  OUR 
CONTINENTAL   UNITED  STATES  TOLL 

FREE  WATTS:   1_800-527-3460 
Texas  Residents  Call  Collect 

214/271-0022 


S.  D.  SALES 
P.O.  Box  28810- A 
Dallas,  Texas  75228 


ORDERS  OVER  $15.  CHOOSE  Si.  FREE  MERCHANDISE 


199 


OUTPUT 

VfllUgu  •}  8t  Or; 

CuiJTjfcMI 

^.i  ■;■■■  'nji 

n  P3'c  i  v.- 


SIZE,  INCHU 


3rj  Hi  *  t  A- 


5TACO  POW  Eft  SUPPLY, 

Converts  S^andw  d  Ha  me  bo  Id  Voltage  into  Regulatec 
13.8VDC  "'■■  4Ar    ld«<il  For  Car   fediai,  Tape  Players, 
Mobile  C.B-.   Radios  £  Communications  Equipment,     Suitable 
For  12V  Trickle  Charger  and  as  Bench  Supply  For  experimenters 
Automatically  protected  from  overloads  and  short  circuits. 
Full  90  Day  War  runt  y  ! 

KPS-*,  ,.,,,, ,  11*1*1.  ......  S37  h95  ppd .  (U,  S,Onlyi 

Outside  U.S,  odd  Shipping  for  5  |bs. 


DC  to  DC  CONVERTER  MODULE.    Tiny  potted  module  is 
complete  regulated  output  up-con  verter,    4.5V DC  input 
provides  appro*  imotely,  14V  ":   [2mA.    Will  operate  down  Id 
2.5V  with  reduced  output.    Operate  digital  clocks  from  3 
or  4  f.5V  batteries  or  put  a  clock  in    your  old  6  V  got.  Only 
I   X;  uXy  "  parted  module,    V^dEagram       DCCI 412P. .  Si  .25 


BiMOS  Operational  AmpliFTer  RCAs  New  CA314Q  combines 
the  advantages  oF  higVvoUage  PMOS  transistors  with  bi- 
polar transistors  on  trie  Same  chip.     Pin  compatible:  with  the 
popular  CA3130  and  directly  replace*,,  in  most  coses,  the 
widely  used  74k    Input  impedance  if,  get  this,  I.STchms, 
wirh  10  pA  input  current  -  how  do  you  measure  that  ? 

CA3T40T    (TO-5  canl. .  . Cheap. .  ,51  .  TQ 

20  page  booklet  oF  spec*... .  ..,.,..,,.,. .  ., 60 


HIGH  VOLTAGE,    High  Speed  NPN  Switch,,     Brand  new 
type  for  di«  in  switching  inductive  loads  such  as  switching 
teaufatore,   Inverters,  mo  tor  controta,  so  I  en  o  Ed's/re  I  ays  and 
deflection  circuity* 

M  J  El  3002  MJEf3003 

VCEOfeu*)  300V  4O0V 

VCEV  600  V  700V 

IC(coni:i  1,5A  1.5A 

fpsokj  3.QA  3.CA 

Packaged   in  the  77-03  caael'TO-1  26)f    these   little  units  pack 
a  bunch  of  performance   in   q  small   space  at  the   right  price! 
MJH3002 SKAQ     MJET3003. . .  . , . , , „.,  .$2.0? 


•  ■ULTfiA  SONIC  TRANSCIEVER.     LMIB12  is  a  special    IC 
cantoing  a   12W  transmitter,   selective  receiver,    noise   re- 
liction circuitry,   display  driver  and  keyed  modulator.    Use 
In   Sonar,    burglar  alarms,    liquid   level  control,   direct? 
control   for  model  submarines,   etc* 
LM1B12. 5?,  15.      Specs  and  ppps,...oOc 


ion 


FLUID   LEVEL  DtTECTOR.     LM1B30  integrated   circuit 
compamnf  external   probe-tpprobe  resistance  with  a  reference 
resiifoi.    Use  as  water   level   detector  or  with   any  pp|ar 
fluid,    ^mo-ke  detector   can  be  made  by  substituting  photo 
cell   for  trie  "laid  probes, . ,  .etc, 
LMlS3Qr..»S2«99,   5pecs  60c  rSpecs  ore  in  NS  Linear  book) 


24  PIN- 1 C  5CXTKET.    Rugged,  extra  quality  socket  mode  by 
Sahinsan-N-jgenr.    Heavy  gold  plated  contacts.    Body  Is  2 
piece  riveted  construct  Eon.    Can  be  soldered  into  PC  board, 
ar  body  mounted  to  endssis  through  2  Counter  tltrjk  hales  in 
body.     RNS-24Q3....  Exfrro  special  ad  price,, ,,,.    2/B8e 


BALUN  CORES      "Binocular"   ferrite  care  far  use  in  wind^ 
ing  holun  transormers  toi   t>«ft4mltt«jr  0'jrPuKr   antenna 
matching,    etc,       .55"   brig    X    .5M   wide   X    .3"   thEck    wM 
■  125-1  dig  hates.    FBC-2760. 10/S2.0Q 


TIME  DFI.AV   MODULE.      I15VAC  input,   4BVDC  delayed 
ojtpur.    .Vill   drive  rehys,    lamps,   etc.      U5VAC  reloj   up 
to  <:houl    br,    .=p||    y^rkt  oerfectly    with    this   unit.       Delay 
tidjujtabte  from  about   2  m  ha  ova*   T   minute-. 
TD.M-013?., 5?i95 


n 


LfD'i.      Brand   ni&v.    by    Woni^ntD   ar    H,*. 
Aycllabfe   in  green   Or   omber.       Arv    MEx , 


Prime   PartjH  i 
.8 ''SI 


m    ■■•■*-■ 


HQ  ft    9HEC  T  «TAL 


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IH5UL*TINe 


CHASSIS  0" 

WStL*TW« 
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lXE*RfthCC 
H0L£3 


HQL£5 


16CMET 


Ml>-20  MdontFng  Kit  'or  TO-3,     Frpm  famous  maker  of  power 
deuces  and  mounting  hardware .    Contoins  woFar  socket,  drill 
templotes,  teflon  bushings,  mount tng  strews  and  anodized 
aluminum  ins.jlator  for  good  heot  conduction. 

WK-20,  iit„iti,Mi«r,lltrMIM»r20    Kitj ,$3.88 


fcf  m 


SPDT  DIP  SWITCH.      Same  os  our  very  popular  GRAVHILL 
DIS-7oBXX  serres  escepr  contacts  are  SPDT*      Rt  DIP  hole 
pattern.      Two  sizes.      Lost  2  digits  indicate  number  of 
switches.    DIS-76CQ2t.,$3,7$       Dl S-76CG4 S4.30 


PRECISION   REFERENCE  DIODE,     IM399  h  a  temperoture- 
ttdbfiited  monolithic  lener  and  buFfef.    Internal   heater 
stabilized  autput  to   .00O2%/°C.   Suffer  reduce*   Zener  im- 
pedance to   ,5  ohm.    Use  En  lab  standards  and  calibrators, 
power  supply  references,   etc.    Initial  breakdown  it  6.95V, 
-5%.        Specs  ore  in  our  National   Linear  Book, 
LM399H,... $5.95 


OUTDOOR  _$PEAKER,       A  quality  5"  horn  speaker  by 

SI  I .?5ppd 


CULVER.     8  ohmr    10WJ     CES-8 


•i     ■     ■     ■     r 


NI-CAD  BATTERIES.     Brand   New  Union  Carbide  recharge- 
able A, 25V,   400mAH  hattery  packs,    Long  color  coded  wire 
leads.      NC&-6252 ...,,J3,25r   4  pack*,.  J|  2. 00 


COAX  Quick   Disconnect  Adapter.   Converts ' PL259  Fnto  a 
push  on  quick  disconnect  For  UHF  type  jacks,    Simply  screw 
PL-259  Fnto  the  threaded   fack.   A  real  time  saver  for  test 
and  alignment  of   RF  Bciuipmentj,  patch  panels,   multiple 
antennas,   etc.      F7t-Qo4,  , ,. ,.,.,,♦.*.  .12.29 


=r 


SUPER  SMALL  REED  RELAY 

Only  3/16"  dEa  X  3/4"  long.  SPST  N,0»  contacts  rated 

]  amp  !    Coil  is  12VDC  at  only  SmA--5/8'f  wire  leads  far 

P»C  or  terminal  strip  mounting. 

RRY-372-1  A. , , $1.19 


HIGH  VOLTAGE  SILICON  NPN 

2N6593  is  a  minimum  250V  fiVCED  High  Voltage  amplifier 
transistor  designed  far  horizontal  drive  applications,  high 
voltage  linear  amplifiers,  and  high  voltage  transistor 
regulators,    in  the  plastic  tab  duo-watt  package-handles 
2  watts  in  Free  air.    Typical  Ft  is  I0OMHZ.    Use  this  one 
in  your  Keyer — - 
_2N6593 p:M $2.06 


MINIATURE   SPEAKER.      Tiny,    football  shaped.     Only 
1-1/8"   X  2-3/S;1  X  3/4"   high,     8  ohm  V.C.     2Q0mV. , 
iViiniature  Speakei Si  .^9,   3  '54.  X 


tRi  -tekr  inc. 

alen^Ale,  ARizoru  8^301 


«£& 


^      '■  ^A~   - 

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INTRODUCES 
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to  potnt  of  measurement,      No  need  ro  turn  your  head 
and  rEsk  shortEng  the  circuit, 

fVess  to  read  switch  extends  battery  life. 

.Auto    Polarity 

.Autp  Decimal 

.Auto   over  range    fndftatai 

,BurJt   in   Battery   Test 

, flanges  0  to     ?9,99V 
0  to    199.9V 
0  to     1000V 
Overload  protected  to   1  KV  -  1    MEG  Enpul  impedance 
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Model   180  DVM ..,.$79,95 

Leatherette  Case ...,,,,  ,,,H, ,,  ,,..56.95 


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SPEEDY  UND  LEAD  FORMER.  One  ot  rhe  simplest  and 
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Rod! used  edges  g'w^  perfect  bend  radius  on  leuds. 


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CMOS  STOPWATCH  CHIP. 

INTERSIL  SCM7205IPG  has  on-chEp  osciltator  and  6  digit 
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battery  smirches  and  LEOS,    Has  START/STOP,  TAYLOfi 
ar  SPLIT  modes.    59min,  59,99  sec  range.    Low  battury 
indication.           ICM  7205  IPQ. .  S19,95.       Data..,  90c 
Crystal    For   the  above .....  * T  .,,...*....  ^S4,95 


Miniature  50  Ohm  Coo^,     RG-174/U  is-ideal  for  use  in  port- 
able, OR?H  test  equipment,  etc.    BRAND  NEW  From  famous 
maker.     Only  1/1 0"  diameter, 
SG-I74/U. .. . . 10-/  S  .95 


TO-3  Power  Device  Heat  Sink.     For  single  TO'3  transistor 

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DTL   INTEGRATED  CfGCUlTS,     Use  DTL  anywhere  you  use 
TTL  J*hen  yod   don't  need   the   high   speed.    DTL  does  not 
produce  the  switching   "notch"   noise  as  does  TTL,      In 
many    cases   the  pin-outs  are   identical   so  you   can  plug 
in    DTL   directly.     Numbers    in    parenthesis    ore   pin    com  pat - 
fete   TTL.     946  -7400!,    960  1741©},   930    7420k 
All    aie   in    14   pin   alaslic   DIP.      DTL,    any    mix ,..,  J0/S1 


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TOUCH  TON FGENERATO*   BY 
MOSTE*,    M K5096N  c*od«es  the 
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-ling  ii  gnats  as  ur»a  h>  TT  e>Kem«t 

.-  :•   r.-:  ::':"t;        .  ■-  .     MWqstf  ?     I 
ctfitali,      -f.  ifo"  and  I  capacitor. 
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f«*g  additional  output  swircnes  can 

ee'<  *e%  enable  audio  amp,  etc*     Lhet 
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of  ports  iftttud+ng  etched  and  drilled  «*.C  .  Coord  entf  one 
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'^r44!2  UNIVERSAL  AflODEM  CHIP 
MCI  4412  contains  □  c^alere  FSK  modulator  ond  do-trod- 

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■13-600  &P 

FEATURfS 

,On  chip  crystal   oieillatar 

*  Echo  luppreisat  diioble  tone  genera  for 

,  Originate   qnd   anjwer    modes 

.Simple*,   ha[f*dupl*Xj   ond  Full  duple*  operation 

.On  chip  tine  ^ove 

.  Mod  em  la  If  tail  muds 

.So  I  actable   da  fa   rat  ay    D-200 

D-30Q 

MOO 

.Single  supply 
VDD=4.75  to  J5VDC  -  FL  luffl* 
VDI>*4-75  tD  a  VOC  -  VL  suffix 
TYPICAL  APPLICATIONS 

.Siand  alone  -  l&w  tpeed  modems 
.BulN   -    in   low  ipeed  modems 
.Itmort  letminolt,   oecauttie  couplers 

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Crystal   tor  the 


14  95 


MO  44 11    BfT   SLATE   t-E^E-.±~:: 
Single  chip  For  generotir^j  selectable  Frequencies  for  equip- 
ment in  data  eoavnunp  cations  such  as  TTY,,    printer*,   CRT  t 
ar  nueropraceitars.      Generates  11  different  standard     bit 
teres  which  arc  multiplied  under  external   control  to     TX# 
flX,    16X  or  64X  initial  value.     Operates  from  single   '5 
voir  mpply,       MC144H  ..... i. .......,,,-,  »,,<*   $H#98 

4  pages  o '  data .  *  % . , . . .  «i .  *  *  *  <  ■  ■  *  •  ■  *  ■  * » » *  &  * » *  *  ■  ■ « ■     *eu 
Crytto  I   For  rha  above  *  *  *•**■■,!»  •  t ,  T « . . . . .  ...*** «    jc*  *  t  j 


REMOTE  CONTROL  TRANSMITTER,     MCI4422P  fi  o  22 

chonnel  y1tra*sorttc  remote  control   rrommitter  t.C.     CMOS 
uiet  little   power  and  only   a  fe*  external  pasiWe   compan- 
entf.   Applicatiam   Include  TV  receivers,   security  OOotTotlj 
toy*,    induitriol   control*  and  lock*.    Tfi  pin  DIP  p Lottie  pkg. 
MCIW22P with  spegs ,  *.<  iimm  SI  1  ,10 


If  your  projec  scharfulef  are  slipping 
one  >oa>*  taking  lumca  with  hi^h 
D*-Tc«  end  poor  tervice,  1e*  »he  guyi 
at  Trl-Ttk  put  it  on  ice  tor  yov 

tnd  ^bepjf  Hoi. 


on 


PRECISION  REFERENCE  AMP 

LH0Q7Q-1H  provJdaj  a  precise  10.0  vol  hi  for  uie  in   BCD  A 
to  D  converter i  or  meter  calibrators,   Typical   initial  accuracy 
is  43%  {-   ♦03V1 .   Come*  in  T0^3  can, 

L  nLTU  *  V*  J<<>l-r*BTaaili-li    +    l-14  W"!  Til      5  p*B  C  J  t-i^i-fif-ffteil    -*3  *  v3 


-*  OtG^T  COUNTtft.    MrV74Cv26  ii  o  *  digEr  coorrtar  with 
7  segment  output  a    Carry  output  tor  cascading  and  internal 
display  select  allow*  frMtauttino/  af  counter  a*  set  a' 
■nternol  loteheA.    3  to  ov  operation.    G?eot  to'  cloct-i, 
•  v*nt  and  freoueacy  cau-nfen. 
V.U74CV26  -    «^th  ipec  sheet. _„......  ST  2 .00 


3  DICADii  tKC     ...       :     CHIP 
V*CU5S3&CP  consliti  of  3  negative  edoe  * 
synchrano^a  counters,,    j   -.-r     i'zim  and   seiF  scon 
RHittiplexed  r   TTl  compatible  ^utputf. 

spec  sneeri..  ■,*.,«■*••■«*■■■«••>»->'>'•* m»r.+wi  *«Ov 


FTirpf  COOf  cONv^srON  c- 

r 22091   sop-t"!  5  Stel  Sender  into  B  twvel  ASCII.   Use 
thii  chip  ro  moi(*  vou*  nld  TT>    talk  to  yoj*  new  campv'»iF . 
""  ^*  «uo  l,  . , .  T  P ,  < .  i  «!»»+**,... ......  .....»,„,.,.    Si  B  i  00 

Specs  'o*  the  ab&vt ...,,, *  *  * ,30 


GOLD  CHIP 

Linear   Integrated  Circuits 

Brand  new  procais  by  RCA  fn  which  the  aluminum  metoJlut. 
hai  been  replaced  by  gold.    Tne  chip  k  then  hermeticalJy  teal- 
ed.    What  thie  immi  fo  you  ij  unprecectenied  reliability  and 
uniformity,    Plajtf c  porti  that  meet  mFJ  ipeci  r  I 
Tri-Tefc  ii  proud  la  be  the  Hm  to  bring  this  new  level  of 
peHoonaace  to  jroy  at  SURPLUS  PRICES,    Why  buy  reofodet?? 

.Improved,  genera  I  purpose  oc-afp,8  pin  dip. ,59c 

.Super  741    op-amp.   B  pAn  dip,., ,5?c 

.Compensated  owod  op-omp,  14  pin  dip.. _* Si  .80 
•  Lo*  offset  quod  comparator.  14  pin  ddp.«.$I.S9 
.Fomovt  general  purxxHe  ca^jr^t  g  p*n  dtp.,  4Sc 
.Genetol  purpose  dual  op-^ama,  14  pin  dip,.,  t2e 
.EVternoIfy  ce^pefaored  74lf  8  pin  sfip.  .4P« 

.General  j»Kpmm  dud  op-onp.  8  pin  olp,..„6*« 
.Quad  Single  supply     S-16V>  op  oeap.   14  pin.*  &*< 


CA30IA, 

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CA748C. 

CA1458. 

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Anather  super  bjy  ftoisi  ICA,  CA555  timer.  0  pin  dip,  59c 


ALPHA- NUMERIC   KEYBOARD 
Mode  by   LJcorv  for  Motorola  Dote  Systems    loelude*  full   upper  cote  alpha  ond  numeric  with  fapqrate 
il'     *f//>    numeric  ond  Conor  control  pods,   5*1;  teonning  wEth   ROM  encoder.   Theie  beautiFul  kevboordt  am 
modetn  design  and  recent  manufacture. 

Outputs  ore   TTL  compatible  and   have  open   col  lector  buffers  with   resistive  pull-up^    Encoding   h  In 
ASCII  with  same  special  control  cadet.   Cod*  table  it  supplied. 
There  a**  only  a  few  of  these  high  puotJty  KB")  ond  of  our  price  they  worit  (ait  long S3*,?5 


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UCOMOUOOt 


NATIONAL  SEMfCOl 

TTL,   OH,   Trf-StBte,  »fC,    .....   S3T9i 

art  amplifiers,   are-ornpt,    oo-amp,,    ..    S3.95 

L  NcA-J  AaPLfCAT:QNS.      Ooiam  of  application  notes  and 


technical  briefs  co^e'inp  the  js*  of  op*amaf,    regu!o+on, 

phase  lackad  loops  and  audio  amps... ..  Vol   * S3. 25 

CMOS    Gores,    PJie  Hops,,  retffftart,    rumdtonci  blocks  S3 
VOLTAGE   ■cC--,.J.7QES.      A  •m«t   For  anyone  moklr^  a 
o&wer  luapfy.  Complete  theory  Including;  *ron*fdn«e<i, 
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MEMORY.     Inroriearion  on  MOS  <tr*S  fliaator  mer^O'i« 

lAAnl       RCVS,     "CVS    ^-J!     iKBdCfl    r-:r^-^..     ..         S3  .  « 

INTERFACE.     Covers  peripheral   driers,    <evel   tronttofors, 
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driplay  driver  and  opto-c<juolt's 53.95 

'Guttlde  U.S.,   add  postage  to*   f.Slbt' 

SPECIAL  FUNCTIONS  DATA  BOOK     canfaim  detailed 

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converter  oraduct* , ,,,...  1 1  „  .53.25 

AUDIO    HANDBOOK       C0rrra.ni   dataffert   dFllpUf^fpni! 

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NEVrf  NAf  (ONAL  BOOK— LINEAR  APPLICATIONS  VOL  II 
Takei  Mp  where  Vol  I  let  you — All  the  latest  Itutor  devices , 
Along  with  Vol  '  you  have  a  great  source  of  flpptication 
date  an  the  mast  hirldely  used  devices  -m  *el  t  as  ne*  types 
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New  book  from  05SQ5NE 

The  fUrif  a^-rtof*  of  rhii  clastic  *ct  o  huge  success.    No*-, 
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73  MAGAZINE  •  PETERBOROUGH  NH  03458 


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punctuation  to  pass  the  test.  Characters  are  sent  at  13  wpm  and  spaced  at  5  wpm  to  get  your  ear  trained  to  the 
sound  of  the  characters  once  without  the  exaggerated  slowness  of  some  systems.  Tlie  other  systems  require  you 
to  train  and  re-train  for  each  of  the  different  speeds.  With  our  tapes  you  will  already  know  the  sound  of  the 
faster  character  and  as  you  progress  through  the  code  speeds  only  the  spacing  is  shortened. 

After  you  have  learned  the  alphabet,  numbers  and  punctuation,  advance  right  away  to  the  6  wpm  tape  which 
in  fact  again  is  the  13  wpm  character  spaced  at  the  6  wpm  speed  needed  to  pass  the  Novice  Class  license  with 
ease.  Study  habits  vary  but  about  4  hours  devoted  to  copying  this  tape  should  have  you  ready  to  pass  your  code 
test.  You'll  be  so  well  prepared  that  you  won't  have  to  worry  about  that  nervousness  that  sometimes 
accompanies  you  when  you  are  taking  a  test  ,  .  ,  you'll  actually  think  they  are  sending  the  code  too  slowly  while 
you  are  being  tested. 

The  73  Nbvice  Class  Study  Guide  and  Novice  Theory  tapes  work  hand  in  hand  to  explain  in  detail  what  is 
expected  of  the  Novice  ticket  holder  «  *  .  The  Novice  Theory  4  tape  set  has  three  tapes  of  theory  which  explain 
the  material  so  thoroughly  even  a  person  with  no  previous  electronic  background  can  easily  comprehend  it;  the 
fourth  tape  has  questions  and  answers  to  prepare  for  the  FCC  Novice  license  test.  The  beauty  of  the  tape  study 
guide  combination  is  that  you  can  repeat  those  areas  of  the  theory  that  you  may  not  understand  over  and  over, 
reinforcing  the  concepts  until  comprehension  (not  just  memorization)  takes  place.  HINT.  While  you  are  learning 
the  code  and  theory  from  the  tapes,  especially  if  you  haven't  been  in  the  habit  of  studying  for  a  while  and  your 
concentration  leaves  something  to  be  desired,  you  might  find  it  advantageous  to  listen  to  the  tapes  only  a  few 
minutes  at  a  time  and  quit  before  your  mind  has  started  to  wander  and  you  start  to  get  discouraged  .  .  .  increase 
your  dosages  each  time  you  study  —  in  this  way  you  can  build  up  an  understanding  as  well  as  sneak  into  good 
study  habits. 

This  package  can  make  a  thoughtful  gift  for  your  son  or  daughter,  niece  or  nephew,  or  grandchild,  especially 
if  they  have  been  hooked  on  CB  and  show  an  interest  in  amateur  radio  .  .  .  you  do  want  your  gift  to  be 
recognized  at  the  BEST,  and  one  that  will  be  remembered  in  years  to  come! 

73Ts  BEGINNER'S  BARGAIN  is  designed  to  save  you  a  little  money  while  allowing  you  to  get  the  best  code 
tapes,  study  guide  and  Novice  theory  tapes  that  are  available  anywhere  at  any  price.  Order  yours  today,  supply  is 
limited. 


_  Beginner's  Bargain  (s)  including  Novice  Class  License  Code  Tapes,  Theory  Tapes  and  Study 


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73  MAGAZINE  -  PETERBOROUGH  NH  03458 


December,  1976 
Dear  YL  and  CM: 

During  this  holiday  season  we'd  like  to  take  a  moment 
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TEST  EQUIPMENT  LIBRARY 
Vol,  III,  Radio  Frequency  Testers 

Radio  frequency  waves  are  the  common  denominator  of  Amateur  Radio  so  here  is  a  book  for  ail  hams. 
No  matter  what  your  specific  interest  such  items  asSWR,  antenna  impedance,  fine  impedance,  RF  output 
and  field  strength  shoufd  interest  you.  This  book  not  only  gives  detailed  instructions  on  testing  these  items 
but  includes  sections  on  signal  generators,  crystal  calibrators  grid  dip  oscillators,  noise  generators,  dummy 
loads  and  much  more.  It's  a  must  for  all  up-to-date  shacks. 
Test  Equipment  Library 
Vol.  Ill,  Radio  Frequency  Testers  T  _  . . . $4.95 

Available  November,  1976 

TEST  EQUIPMENT  LIBRARY 
VOL.  II,  Audio  Frequency  Testers 

HOW'S  YOUR  SPEECH  POWER?  YOUR  SHIFT?  YOUR  SYNC? 

You  can  find  out  easily  with  a  little  time  and  a  junk  box  full  of  parts.  It's  at!  right  there  in  the  new 
Volume  II  of  the  73  Test  Equipment  Library .  .  ,  Audio  Frequency  Testers .  .  .  jam  packed  full  of  all  kinds 
of  audio  frequency  test  equipment  So  if  you're  into  SSB,  RTTY,  SSTV,  etc.,  this  book  is  a  must  for  you 
.  ,  .  good  book  for  hi-fi  addicts  and  experimenters  too! 
Test  Equipment  Library 
Vol.  It,  Audio  Frequency  Testers , , $4.95 


Available  October,  1976 


TEST  EQUIPMENT  LIBRARY 
VOL.  I,  Component  Testers 

Just  out  is  Volume  I  of  the  73  Test  Equipment  Library 
.  . .  how  to  build  transistor  testers  (eight  of  'em),  diode 
testers   (3)f    IC   testers   (3),   voltmeters  and    VTVMs   (9), 
ohmmeters   (8  different  kinds),   inductance   (3),  capacity   (9j,    Q  measurement,   crystal  checking  (6)f 
temperature  (2),  aural  meters  for  the  blind  (3)  and  alt  sorts  of  miscellaneous  data  on  meters ,  .  .  using  them, 
making  them  more  versatile,  making  standards,  things  like  that  Invaluable  book,  ridiculously  low  priced. 
Test  Equipment  Library,  Vol  I,  Component  Testers  .  .  . ...*.......  $2,95 


Send  me: 

CI  Vol .  1 Component  Testers 

□  Vol.  IL.*  Audio  Frequency  Testers 
D  VoL  1 1 1...  Radio  Frequency  Testers 

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79  magazine       •Peterborough  NH  03458 


12/76 


j 


207 


EDITORIAL  BY  WA  YNE  GREEN 


frontpage  178 


Meet  Fran  Qitfon,  who  handles 
invoicing  for  subscriptions  and  orders 
for  books,  tapes  and  such  items.  As 
more  and  more  of  this  routine  is  taken 
over  by  the  slowly  expanding  com- 
puter system  at  73,  Fran  should  be 
able  to  devote  more  time  to 
expanding  the  Radio  Bookshop 
service,  Fran  also  helps  with  sales  and 
inventory  records,  a  necessary  part  of 
keeping  things  moving  smoothly. 


Susan  Mikula  helps  with  bundling  the 
piles  of  matt  that  pet  sent  out  every 
day.  Note  the  mail  trays  behind  her, 
Marl  for  each  zip  code  center  has  w  be 
sorted  out  and  bundled. 


Virginia  Msmmone  helps  with  the 
pasteup  of  type  to  make  up  the  pages 
of  articles  in  the  magazine.  This  is 
very  exacting  work,  for  each  block  of 
type  must  be  set  in  precisely  right ,  , , 
if  it  is  off  even  a  hair  it  looks  crooked 
to  the  eye  on  the  pages.  Once  the 
pages  are  pasted  upr  they  are  made 
into  negatives  and  printing  plates  are 
made  from  the  negatives. 


s  Richard  Force  WB2QYV/ft 
who's  editing  and  organizing  the  new 
books  which  are  coming  from  73  .  -  . 
and  there  are  a  tot  of  them  in  the 
works,  such  as  three  more  test  equip- 
ment handbooks  .  .  .  a  new  Novice 
Study  Guide . .  .  a  new  Repeater  At  fas 
.  .  General  Class  Study  Guide  , , . 
RTTY  Handbook  . .  .  and  many  more. 


propagation 


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208 


Advanced  Communications  Equipment  from 
the  World's  Leader  in  Amateur  Communications 


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Left  to  right  -   FT-620B,  6  Meter  Transceiver  •  YP-150,  Dummy  Load  Wattmeter  *  YO-100,  Monitor  Scope  •  FTV-250, 
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Left  to  right  -  YC-601 ,  Digital  Frequency  Display   •   YC-355D,  Frequency  Counter  •    FP-301 ,  AC  Power  Supply  •  FT-301S 
Digital,  All  Solid  State  Transceiver  •  FV-301,  External  VFO  *  FT-221,  144-148  All  Solid  State  All  Mode  Transceiver 


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