circuit boards anti -static spray ideas in electronics tv via satellite all about vcr circuits

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Radio Electronics
THE MAGAZINE FOR NEW IDEAS IN ELECTRONICS
Build It Cover Story TV VIA SATELLITE
PERCUSSION SYNTHESIZER What's up there to watch
HI -FI NOISE FILTER PROM PROGRAMMER
Build for 14 -dB improvement You can build it
PRINTED -CIRCUIT BOARDS ALL ABOUT VCR CIRCUITS
Which ones are best Video -signal processing
*
ANTI -STATIC SPRAY HOBBY CORNER
*
Keeps discs dust free COMMUNICATIONS CORNER
PerSyn PerSyn
SNARE
A
6ERNSBACK
PUBLICATION
A
of
lot signal.
cora
cost.
little
We just set a new value standard. Twice.
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FREOUENCY I t0 t00 ta 10a "OE I rL¡T 1AN 1/\, I OA/
6 1 -J
: /
L
RANGE I MODE
2001 FUNCTION GENERATOR
-N 00
SWEEP IN TTL GNO NI LO
(
J
66
CONTIN4NT 4VC I4 CowrowTION
PULSE SPACING PULSE WIDTH 'GA" I 'WO' TQ1G GATF SMOET I WA0s, E CPL I fMOT
AMPLITUDE
,MS 1001441 1. 10.S 1111/ tFrot \ litmi .1 .4 ,to.a I s 400L1 PULMSODEE GENERATOR
4S 1ooMS. >a W4
6111 II GA0TE /TRIG IN SYNC OUT TTL OUT VAR OUT
ED
SPACIV, NNIER WIDTH VERNIER
J
OiSQ COaI.INNT1l 4r4CIALT144 CO111.00..TION
Model 2001 Sweepable Model 4001 Ultravariable
Function Generator. 5149.95' Pulse Generator. S169.950
Get the waveforms you need-1 Hz to MHz in Here's a precision digital pulse generator with
.1
five overlapping ranges: stable, low- distortion fast rise and fall times covering 0.5 Hz to 5 MHz
sine waves, fast rise /fall -time square waves, in 5 overlapping ranges. With pulse width and
high linearity triangle waves -even a separate pulse spacing each independently variable
TTL square wave output. Plus high- and low - from 100 nsec to 1 sec for an amazing 107:1
level main outputs. duty cycle range.
An applied DC Voltage at the Sweep input You'll find the 4001 delivers the pulse
can shift the 2001 's frequency; or sweep up to modes you need: Continuous, One- Shot, Trig-
100:1 with an AC signal. gered, Gated, Square Wave, even a Comple-
A pushbutton activates the DC Offset ment mode. The Trigger /Gate input, 50 Ohm
control, which shifts the output waveform up or variable output, TTL -level output and Sync
down on command. output connectors are BNCs.
You'd expect to pay a lot more for all the The 4001. Nothing does as much as well
2001 can do! for anywhere near the price.
Smarter tools for testing and design.
CONTINENTAL SPECIALTIES CORPORATION
Call toll -free for details
70 Fulton Tyr New Haven CT 06509 12031624 3103 TWx 713465.1227
EOuTrHopEeR OCFSFCIC UEKS LTSDa n PFhroannec iSscaon ro1n4 15W1 a4ld2e1n 80877929 T2W16X6 29 1¡3L.a37 621 77491972 1- 800 - 243 -6077
Canada Len ',miler Ltd Ontario
Suggested U S resale Available at selected local distributors Prices. specdlcations subject tochange without nu; I Copyright 1979 Continental Specialties Corporation
CIRCLE ON FREE INFORMATION CARD
Don't take our word for it.
"We can heartily recommend the Superboard II computer system for the beginner who
wants to get into microcomputers with a minimum of cost. Moreover, this is a `real' com-
puter with full expandability."
Popular Electronics March, 1979
"(Their) new Challenger 1P weighs in at $349 and provides a remarkable amount of com-
puting for this incredible price."
Kilobaud Microcomputing February, 1979
"Over the past four years we have taken delivery on over 25 computer systems. Only two
have worked totally glitch free and without adjustment as they came out of the carton:
The Tektronic 4051 (at $7,000 the most expensive computer we tested) and the Ohio
...
Scientific Superboard II (at $279 the least expensive) The Superboard II and com-
panion C1P deserve your serious consideration."
Creative Computing January, 1979
"The Superboard Il and its fully dressed companion the Challenger 1P series incorporate
all the fundamental necessities of a personal computer at a very attractive price. With
the expansion capabilities provided, this series becomes a very formidable competitor
in the home computer area."
Interface Age April, 1979
"The graphics available permit some really dramatic effects and are relatively simple to
program ... The fact that the system can be easily expanded to include a floppy means
that while you are starting out with a low -cost minimal system, you don't have to throw it
away when you are ready to go on to more complex computer functions. Everything is
there that you need; you simply build on to what you already have. You don't have to
worry about trading off existing equipment to get the system that will really do what you
want it to do. At $279, Superboard Il is a tough act to follow."
Radio Electronics June, 1979
"The Superboard Il is an excellent choice for the personal computer enthusiast on a
budget."
Byte May, 1979
SUPERBOARD II
$279.00
The world's first
complete computer
system on a board IIII1LttENGEIC . 'tir
including full
keyboard, video
display, audio
cassette interface, 8K
BASIC -in -ROM and
4K RAM. Expandable.
Requires + 5V at 3
amp power supply.
CIP $349.00
Complete with enclosure and power
supply. All features of Superboard II. Easy to expand
to more memory and floppy disk.
ci MF $995.00
The first floppy disk based computer
system the world has ever seen for under $1,000.
8K BASIC -in -ROM, 12K RAM. Expandable to 32K RAM.
OHIO SCIENTIFIC
1333 S CHILLICOTHE RD . AURORA. OHIO 44202 (216) 562 -3101 See your Ohio Scientific dealer for lull details.
CIRCLE 19 ON FREE INFORMATION CARD
LABORATORY QUALITY AT SERVICE BENCH PRICES
The most sophisticated scope THE 10 kV post -acceleration volts
-
ever offered in money -saving fastest, brightest display in any
kit form: the new Heathkit EATH Heathkit oscilloscope ever
I0 -4235! Compare its features All these features and more,
...compare prices...and you'll DC -35 MHz in a scope that's surprisingly
ove up to the I0 -4235 easy to build and maintain!
DUAL TRACE Circuit boards swing out for
DC -35 MHz response with easy access to components
smooth roll -off beyond DELAYED SWEE even while the scope is oper-
50 MHz - OSCILLOSCOPE ating. You can make minor
Dual trace study two rvice adjustments quickly and
-
signals simultaneously easily should that ever be
-
Delayed sweep observe any section of a necessary. This Heathkit scope is one of the
-
waveform magnified as needed best values today...and for years to come!
Fast sweep speeds from 50 nS /cm to 0.2 Kit I0- 4235....just $869.95
sec /cm, plus X5 expansion for effective speed Also available factory assembled
of 10 nS /cm at the highest sweep rate and tested....$1195.00
* TV triggering for jitter -free display Prices are mail order net F.O.B., Benton Harbor, Michigan.
Prices and specifications subject to change without notice.
2 mV/cm to 10 V /cm vertical sensitivity FREE HEATHKIT CATALOG!
i
Algebraic ADD with ability to invert Y, or YZ Send for your FREE Catalog with full descriptions of the
Internal graticule for parallax -free ID -4235 and all the other exciting new Heathkit exclusives!
Write to: Heath Company, Dept.020
measurements GX-369 Benton Harbor MI 49022
401111116
CIRCLE 100 ON FREE INFORMATION CARD
Radio -Electronics.
THE MAGAZINE FOR NEW IDEAS IN ELECTRONICS
Electronics publishers since 1908 SEPTEMBER 1979 Vol. 50 No. 9
ON THE COVER
Cover Story
BUILD ONE 43 Polytonic Percussion Synthesizer Fascinating percussion synthe-
Easy -to -build modular system simulates congas, bongos, wood sizer simulates a variety of per-
blocks and timpani. James J. Barbarello cussion instruments. Modular
54 Adaptive Noise Filter accessories make it even more
Part 2: Dynamic variable -cutoff low -pass filter removes the snap.
crackle and pop from records and tapes. valuable. Circuits are straight -
Tim Skormond 8 Gene Garrison forward....construction is
easy....equipment is inexpen-
VIDEO 47 Home Reception Via Satellite sive. Full details begin on page
What's up there that you might want to watch. As many as 40 43.
channels of more television than you've ever seen before.
Robert B. Cooper, Jr.
63 VCR Video Signal Processing
How the video is handled by VHS and Betamax VCR's. Forest Belt
83 Service Clinic
Those pesky electrolytics. Jack Darr
83 Service Questions
R -E's Service Editor solves reader problems.
57 Antistatic Record Care
Spray treatment stops static electricity problems permanently.
Len Feldman
60 R. E.A.L. Sound Lab Tests Setton Receiver Commercial satellite TV receiving station uses
Model RS -660 Stereo receiver earns an "Excellent." Len Feldman huge dish and supersensitive receiver, but you
can build your own. Story starts on page 47.
TECHNOLOGY 4 Looking Ahead
Tomorrow's news today. David Lachenbruch
50 All About Printed Circuit Boards
How to determine which board is best for your application.
L. Steven Cheairs
88 PROM Programmer
Application note tells how to build one. Fairchild Semiconductor
76 Hobby Corner
The programmable calculator -an important tool.
Earl R. "Doc" Savage, K4SDS
80 Communications Corner
Electronic amplification for weak signals is feasibie. Build this adaptive noise filter to remove the
Herb Friedman
snap, crack e and pop from your records and
tapes.
EOUIPMEN1 26 ATV Research MVX -500 RF Modulator
32 American Antenna K -40 CB Antenna
34 Electra 8C220 Programmable Scanner Radio -Electronics, Published monthly by Gernsback
35 Motorola CM540 CB Transceiver PNYu bl1ic0a0t0io3n. sP, hoInnce.:. 221020 -7P7a7rk - 64A0v0e.n Cueo nStrooullethd, NCeirwc ulYaotiorkn,
Postage Paid at Concord, NH. One -year subscription
rate: U.S.A. and U.S. possessions, $9.98, Canada, $12.98.
Other countries, $14.98. Single copies $1.25. © 1979 by
Gernsback Publications, Inc. All rights reserved. Printed
DEPARTMENTS 114 Advertising Index 16 Letter in U.S.A
14 Advertising Offices 94 Market Center Subscription Service: Mail all subscription orders,
90 Books 86 New Products changes. correspondence and Postmaster Notices of
undelivered copies (Form 3579) to Radio- Electronics
88 Communications Products 92 New Lit Subscription Service, Box 2520. Boulder, CO 80322.
14 Editorial 93 Stereo Products A stamped self -addressed envelope must accompany all
115 Free Information Card 6 What's News submitted manuscripts and /or artwork or photographs if
their return is desired should they be rejected. We
disclaim any responsibility for the loss or damage of
manuscripts and /or artwork or photographs while in our
possession or otherwise.
As a service to readers, Radio- Electronics publishes available plans or information relating to newsworthy products, techniques and scientific and technological developments.
Because of possible variances in the quality and condition of materials and workmanship used by readers, Radio -Electronics disclaims any responsibility for the safe and proper
functioning of reader -built projects based upon or from plans or information published in this magazine.
3
Awl*Taie,i
TV sound: With all of the 1980 TV models now introduced, cartridges at $20 each will be supplied by Milton -Bradley).
it certainly can be said it's the year of television sound." RCA's new VIP -II home and business computer has a full
Last month reported approaches to better sound by RCA, keyboard, 8K RAM, 12K ROM, resident BASIC capability,
Magnavox and Sylvania. Zenith is capitalizing on improved but no monitor, at around $400. APF introduced a "dock-
television audio transmission in several ways. A large ing" computer system at $500 for its video game with 10K
percentage of its sets include audio output jacks for attach- RAM, 12K ROM, resident BASIC, color and sound capabili-
ing to external amplifiers. Some consoles feature four ty for use with a color TV.
speakers -two on each side. At the high end of the line are The hand -held "language translators" are rapidly evolv-
sets with separate 10 -watt audio amplifiers, including bass ing into portable computers. TI announced a language
and treble cut -boost controls. Quaser, which for several translator with a voice synthesizer for $300, with $60
years has featured a pseudo- stereo system known as modules containing 1,000 words, all words displayed on
Audio Spectrum Sound, now extends that feature to sever- the readout and half of them pronounced. The translators
al 19 -inch sets and six consoles. offered by Craig and Lexicon increased their versatility with
Among other trends in the new lines are an increased new non -language program modules, including made -to-
emphasis on microprocessor tuning systems that eliminate order custom units. Matsushita announced that it would
the need to adjust fine tuning even once, and more wide- enter the hand -held computer market through agreement
spread use of the vertical interval reference (VIR) signal for with Friends /Amis, which makes the Craig unit, and its
color set adjusting, as well as comb filters for better color American subsidiaries Quasar and Panasonic quickly said
and higher resolution. Zenith has a random -access key- they'd market the units in the U.S. under their own brand -
board tuning system that can tune 105 channels -the stan- names.
dard VHF and UHF channels as well as midband and
superband channels used for modern cable systems. Sony New VCR models: More than 80 different models of
introduced the largest direct -view color sets ever offered in home VCR's have now been introduced (including those
this country -with a 26 -inch Trinitron picture tube that has already superseded by newer versions). Some of them are
a 341 -square -inch picture as compared with 315 for a stan- similar -even identical- except for the brandname, and all
doaffredr e2d5 -icnocmh mtuebrec.i a(lTlyh, e ablisgog esbty coSloorn ytu -bbeu ct urrine nJtlayp baeni n-g afarect ustriell rps,r omduocree d binra Jnadpnaanm. eFso, r 1lo9n8g0e, rt hpelraey ainrge mtimoree manadn ua-
measures 30 inches in viewable diagonal, 32 inches over- host of new features.
all. It isn't offered in a color receiver in the U.S.) The two new brandnames in the U.S. are Akai and Sharp,
both bringing in the first home video recorders produced in
Car stereo fracas: Independent auto sound manufactur- their own plants. Akai's is a two- hour -only VHS unit,
ers have been up in arms about the tendency of car manu- designed for portable operation, lightweight (15 pounds
facturers to include radios as standard equipment in their with battery), but capable of home operation with a
new models, and their campaign against the practice is companion tuner -timer. The Sharp VHS unit records 6
beginning to bear fruit. Aftermarket car sound manufactur- hours per cassette and is programmable, for seven differ-
ers established an organization, the Custom Automotive ent recordings seven days in advance, and contains the
Sound Association (CASA), to push their campaign. video version of Sharp's Auto Program Locate Device
CASA's first major action was an anti -trust suit against (APLD) that can cue up to 99 different places on the tape
General Motors which had indicated that all of its new "X" for rapid access. Mitsubishi's first own -make recorder will
cars would be factory- equipped with AM radios. The suit debut under the MGA label, featuring five direct -drive
never went to trial. In a settlement, GM agreed to allow motors, remote control of most functions, with freeze, fast -
dealers to delete the radios, not to force them to buy forward and slow motion, also in the six -hour VHS mode.
radio -equipped cars and not to make radios standard New Sony -made five -hour Beta models from Sony and
equipment before 1983. CASA then turned its sights on Zenith also have complete remote -control systems and
Toyota and Volkswagen, filing suits against both of them. permit visible fast -forward and rewind for easy program
Presumably reading the handwriting on the firewall, Honda location. Hitachi will have a portable similar to the one it's
voluntarily decided to delete radios as standard equipment making for RCA. JVC, which had stuck with the two -hour
on its 1980 models. CASA also plans to act on the legisla- single -speed concept in its VHS units, has come up with a
tive front, testifying before the Senate Anti -trust Subcom- new recorder containing four heads (a different pair for
mittee on the subject. each speed), now playing in either the two- or six -hour
mode. JVC says the four -head concept permits maximum
Computers for everyman: That all- purpose home com- fidelity in either speed. Its new model permits remote -
puter for the non -technical consumer hasn't yet come to control of freeze -frame, double- and triple -speed playback,
pass -but manufacturers still think it will. Texas Instru- infinitely variable slow- motion. is programmable for seven
ments has unveiled its long- awaited home computer, a days. Sanyo and Toshiba both introduced programmable
$1,150 self- contained unit with its own 13 -inch color tube five -hour Beta models with visible fast -forward and re-
(procured from Zenith) with resident extended basic, a 16K verse.
RAM, 16 -color graphics, a microphone jack, sound synthe- DAVID LACHENBRUCH
sizer and cartridges priced from $10 to $70 (game software CONTRIBUTING EDITOR
On your newsstand September
18...
the
most
57111@
exciting issue any
of
inthe
Twentieth
Century...
October
1979 From "Radio- Craft" in 1929 to
Radio- Electronics today, and tomor-
Radio -Electronics.. row, from the vacuum tube to the
chip, from "wireless radio" to inter-
50th planetary communication -it's fifty
years of history, experiments, and
Anniversary Issue excitement from the pages of Amer-
ica's greatest newsstand electronics
magazine, all in the most spectacu-
lar issue ever of any electronics
w.
magazine -October, 1979
Radio- Electronics.
Don't miss a word of this colorful,
_A
extra -special retrospective issue,
Radio -Electronics bursting with all the excitement of
-or
The all those years of our experts'
number
fascinating projections and predic-
one
authority
tions for "The Next Fifty Years" of
for
50 years. our lives.
It's October Radio -Electronics. On
4011111111111.11111
your newsstand September 18 ... but
not for long. Don't miss it.
-11
wha
news
s
JVC Videodisc Shown
Shown to the press for the first time
during the Summer CES Show, JVC re-
vealed their version of a capacitive video
disc. It, like the RCA unit (Radio- Electron-
ics, April 1979) uses a contact stylus.
Unlike the RCA system it does not ride in a
groove. Instead it rides over the surface of
the disc. Victor claims that capacitive sys-
tems tend to be less expensive that optical
disc systems.
The capacitive videodisc is made of an
electroconductive plastic into which 54,000
spiral tracks consisting of pits in the base
material are formed. During playback the
stylus, mounted on the end of a cantile-
vered pick -up arm, is guided along the disc
surface following the helical track. The
stylus tip contains an electrode that re-
ceives information from the disc. It has an
anticipated life of 2000 hours and as it
wears down, new portions of the electrode
are exposed.
The disc spins at 900 rpm, and with
accessory optional equipment, can provide
a still picture (maximum of one hour playing
time), forward and reverse motion at nor-
mal speed, variable speed slow motion,
Philips Shows Laser -Scanned 4'/ 2-inch Audio Disc variable speed fast motion, and high -speed
Digital technology, combined with laser - pled 44,330 times each second, more than search.
optics, opened a new era in recorded twice the audio bandwidth. These samples It is also possible to add on a random -
sound at a two -day demonstration at New are then quantized and converted into access unit that permits accurate location
York's Plaza Hotel. The revolutionary Phil- binary 14 -bit "words" through Pulse Code
ips Compact Disc system promises an Modulation techniques.
unprecedented improvement in sound Each hour -long CD recording is made up
quality and realism of prerecorded materi- of 6- billion bits, encoded along a helical
al. track of pits on this disc. This disc is quite
Combining videodisc technology with similar to the Philips videodisc described in
pulse- code -modulation and digital record- Radio -Electronics, April 1979 issue. The
ing techniques; Philips showed a prototype helical track is tightly spaced- separation
system that puts one hour of extraordinary between tracks is only 1.66 microns and
quality stereo sound on one side of a 4' /z- 21/2 miles of recording is fitted on each 4V2- and retrieval of desired recorded material
inch diameter disc. The system is expected inch diameter disc. and automatic playback in any mode. JVC
to ready for the marketplace in 1983. The To retrieve the sound, the disc is inserted also demonstrated the ability to use their
home player is expected to be of the same track -side down into the playback unit videodisc player for audio records. To use
size and cost as today's quality players. which permits automatic play or manual the player for this purpose a pulse -code-
The new system converts the original search for a specific selection. A miniature modulation (PCM) decoder is connected to
sound into high- density pulse- code -modu- AlGaAs (Aluminum Gallium Arsenide) di- the player. The random -access unit, when
lation and replaces the playback stylus with ode laser, located below the disc, is fo- combined with the PCM feature provides
a low -power solid -state laser. cused on the track and converts the en- retrieval of any music selection.
Compared to conventional LP and 45- coded material back into an electronic Like both the RCA and Philips videodisc
rpm audio discs, the Compact Disc (CD) signal. The track is scanned from the cen- systems a maximum of two hours of play-
provides a flatter frequency response; es- ter of the record to the outer edge as the back time, one hour on each side of the
sentially flat from 20 to 20,000 Hz with disc turns at speeds between 215 to 500 disc, is provided. The disc measures 11 -1/2
stereo channel separation of 80 dB. Signal - rpm to maintain a constant linear velocity inches in diameter, is Viii-inch thick and is
to -noise ratio and dynamic range are between the disc and laser. scanned by a saphire stylus.
boosted to 85 dB -a substantial improve- The Philips Compact Disc System is the There has been much speculation about
ment over the 60 dB currently available. first of it's kind to be designed for the audio the possibility of JVC and RCA agreeing on
An additional advantage is immunity to market that looks like it may be able to a format for a capacitive videodisc, but to
surface noise and hiss. Since there is no destroy the "distance" (and the difference) date this appears to be only speculation.
stylus riding in a groove, only a laser light between the recording studio and the lis- As of this writing there is no such agree-
beam touches the disc, there is no surface teners living room. It's the first to incorpo- ment and the two disc systems, while hav-
hiss, clicks, turntable rumble, room vibra- rate the digital decoding electronics in the ing some similarities, are not compatable,
tions or pickup arm resonances to detract playback unit and, with the laser scanner, nor is either one compatable with the Phil-
from the recorded sound. it's the first to insure against deterioration ips system.
To convert the analog signal into digital of the recorded material as it is played JVC had no comment on when the play-
form in the CD system, the sound is sam- back. ers would be available.
We confess.
To sell an
advanced
DMM for
under
$70
we had to
cut corners.
And we sure did! First, we cut LED display with automatic decimal placement to -reach places without taking your eyes off
off the dealer's markup. Then and large, 9mm numerals. the probe tip or stopping to record data.
we shaved off the overhead costs Of course, that's what you'd expect from a Plus More - Auto Polarity, Auto Zero,
of national sales offices and quality DMM. But we've even added more Overrange indication and fully overload
warehouses. Finally, as if that features for extra convenience, flexibility and protected on all ranges.
wthaes hni'tg he nloabuogrh ,c owsets e ovfe nfa cctuotr oyu t redUunciqtiuoen oXf1 0h uMmualnti pelrireorr .S witch - gives you sAlenedk,, aclothmopuagcht 2d0e1si0gAne ids fpoorw beerendc hbtyo p4 u"sCe," tcheell s
assembly lines. convenient push -button selection to the next (not induded), bringing wide -range lab
All in all, we cut over $100. higher decade range. Hi -Lo Power Ohms performance to the field when you need it.
worth of corners! But not a cthaapta sbuiplitpyl yg ievenso uygohu vthorlteaeg eh itgoh -rouhmm os nr aan ges You save either way.
sqiunaglliety o naen dt hpaet rafoffremctaendc eth oef our steilsictionng .j uFnocr tiino-n c ifrocru idt iroedseis taanndc er rmanesaissutorer ment Yeaosuyr - t2o-0 f1oClloAw D aMssMem kbilty c ionmstersu cctoiomnpsl,e taell wpaitrhts
new DMM. without turning on a semiconductor junction, (induding high -impact case), and test leads. You
Don't let our low price foo-l you! yWoiud eus Fe rtehneq uthernecey loRwes -poohnmsse r-an 4g0esH.z to cHaonw ceovmepr,l eftoer aas sseligmhbtl ya idnd ait iosinnaglle f eeev, eSnainbgtr.o nics
Because Sabtronics sells factory-direct 40kHz bandwidth lets you measure audio will ship your 2010A factory- assembled and
without a-ll the hidden charges a dealer would through ultra -sonic AC signa-ls . calibrated: at $99.50 it's still an incomparable
track on we can offer the superior 2010A Touch and Hold Capability with optional value!
DMM kit for a surprisingly low $69.95. probe, retains readings for as long as you Whether you're a professional or h-o bbyist, if
Surprising because you get the accuracy, wish. You can make measurements in hard- quality and accuracy -ar e important and
features and performance you'd expect from the padded prices aren't you should inspect the
high priced units. 2010A DMM for yourself. If you're not
The 2010A offers you the long -term accuracy completely satisfied, return it in its original
of a laser -trimmed resistor network, an ultra - condition within 10 days for a prompt and
stable band -gap re-fe rence element and single courteous refund of purchase price. Call us
chip LSI circuitry all in a compact, rugged, with your MasterCharge or Visa order today,
human- engineered housing. With 31 ranges or simply fill out the convenient order form.
and 6 functions, you can measure AC and DC Making Performance Affordaole
volts from 100 µV to 1000V; AC and DC sabtronics
current from 0.1 pA to a surprisingly high 10A;
resistance from 0.111 to 20 Ma Typical DCV ,;r.,AL we
and Ohms accuracy is 0.1% ± 1 digit. And you 13426 Floyd Circle M/S 35. Dallas, Texas 75243
see these precise readings on a bright, 31/2-digit Telephone [phone]
Brief Specifications To: Sabtronics International, Inc. 13426 Floyd Circle M/S 35, Dallas, TX 75243
DC Volts: 10022V to 1000V in 5 ranges Please send me . .
AC Volts: 100µV to 1000V in 5 ranges Model 2010A Digital Multimeter kills) @S69 95 plus $4.001 shipping and handling each S
DC Current: 0.1µA to 10 A in 6 ranges Model 2010A Digital Multimeter Assembled @ 599 50 plus $4 001 shipping and handling each S
AC Current 0.1µA to 10 A ln 6 ranges sr AC-115 AC adapter /charger(s) @$7.50 each S
Resistance: 0 1St to 20 MS) in 6 ranges a NB -120 NiCd Battery set(s) @517.00 /set S
DACioVd eF rTeeqsut eCnucryr eRnet:s p0o.1nµsAe.: 1400µHAz, 1t om 4A0 kHz _Foar T HdPel -iv2e0 ryT oinu cThe xaansd. Haoddld 5P%r oSbea(less) @Ta5x 18.00 each SS
Input Impedance: 10 MU on ACV and DCV lo re, npclleoassee O c hcahregcek to Dm ym onOe yV iosrad er toMra sterCharge Code a TOTAL S
Overload Protection: 1200 VDC or RMS on all voltage Account No Expiration Date
ranges except 250 VDC or RMS on 200mV and 2V AC
ranges Fuse protected on ohms and mA ranges. Name
Power Requirement: 4.5 to 6.5 VDC (4 °C" cells)
optional NiCd batteries or AC adapter /charger Street Apt
Display: 0.36" (9.2mm) Digits reading to ± 1999
Size: 8 "W x 6.5 "D x 3 "H (203 x 165 x 76 mm) City State Zip
Weight: 1.5 lbs. (0.68kg.) excl. battery LCdnhnantal U S only AK HI 8 PR $500 Canada:S6 50. Foregn $19 00 Anma,l
7
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Communications Course covers
all types of two -way radio equip -
ment...AM and FM transmission
and reception, television broadcasting, back agreement is good for six months and 10 training kits. Included are
microwave systems, radar principles, after completion of your course. your own electronics Discovery Lab®
marine electronics, mobile communi- Learn on your own 2- meter, antenna applications lab, CMOS
cations, and aircraft electronics. And digitally synthesized digital frequency counter, and 7 -scale
NRI guarantees you will pass the exam VHF transceiver. AC /DC volt- ohm meter. You'll learn at
for the commercial FCC Radiotele- home, at your own convenience, get-
You'll learn to service all types
phone License you need to perform ting the training you need for your
of communications equipment as you
most servicing work, or your tuition FCC License and the communications
will be refunded in full. This money- assemble your own VHF transceiver. field of your choice.
NRI engineers have designed it, not
only as a commercial -quality; high - CB specialist course
also offered.
performance unit, but as a unique
"power -on" training tool to give you If you prefer, you can concen-
actual bench experience with the prin- trate on the big field of CB radio with
ciples needed to service commercial, NRI's special course in CB servicing.
CB, and amateur equipment. You get 37 lessons, 8 reference texts
Then we help you get your and plenty of "hands -on" training
FCC Amateur License so with your own 40- channel CB, AC
power supply, and multimeter. Also
you can go on the air.
included are 14 coaching units to
The complete course includes
make it easy to get your commercial
48 lessons, 9 special reference texts, Radiotelephone FCC License...required
for you to test and service communi-
cations equipment.