ZX81

ZX81 Kit

Order at no risk .*We'lI give you 10 days to try out the ZX81 . If

you're not completely satisfied, just return it toSinclair Research and we'll give you a full refund .

And if you have a problem with your ZX81,send it to Sinclair Research within 90 days andwe'll repair or replace it at no charge .Introducing the ZX81 kit.

If you really want to savemoney, and you enjoy building elec-tronic kits, you can order the ZX81in kit form for the incredible priceof just $99 .95 .* It's the same, full-featured computer, only you put ittogether yourself . We'll send com-plete, easy-to-follow instructionson how you can assemble yourZX81 in just a few hours . All youhave to supply is the soldering iron .A leader in microelectronics .

The ZX81 represents the latest your

in microelectronics .More than 10,000 are sold everyweek. In fact, the ZX81 is the fastestselling personal computer in theworld .

We urge you to place yourorder for the ZX81 today.To order.

To order, simply call toll free .Or use the coupon below . Remem-ber, you can try it for 10 days at norisk.* * The sooner you order, thesooner you can start enjoying yourown computer.Call toll free 800-543-3000 .

Ask for operator # 509 . InOhio call : 800-582-1364 ; in Can-ada call : 513-729-4300. Ask foroperator # 509 . Phones open

NEW sOFTWARE : Sinclairhas published pre-recordedprograms on cassettes foryour ZX81 . We're constantlycoming out with new pro-grams, so we'll send you ourlatest software catalog with

r computer.

Name

Address

sinclairTo order call toll free : 800-543-3000r~~~=====M E '

Ad Code 06PE

MAIL TO : Sinclair Research Ltd .,One Sinclair Plaza, Nashua, NH 03061 .

City

24 hours a day, 7 days a week . Have yourMasterCard or VISA ready.

These numbers are for orders only. If you justwant information, please write : Sinclair ResearchLtd ., 2 Sinclair Plaza, Nashua, NH 03061 .'Plus shipping and handling . Price includes connectors for TV and cassette, AC adaptor, andFREE manual .**Does not apply to ZX81 kits .

ZX PRic i Ln .Printer will work with yourZX81 . It will be available in thenear future and will cost lessthan $100 .

Price*

16K MEMORY MODULE :Like any powerful, fullfledged computer, the ZX81is expandable . Sinclair's 16Kmemory module plugs rightonto the back of your ZX81 .Cost is $99 .95, plus shippingand handling .

Qty. Amount

StateZip

$149 .95

99 .95

16K Memory Module 99 .95

Shipping and Handling 4.95 $4.95

TOTAL

Few Years Ago,he Idea of ar You Could

r Pocketas JustFiction."ac Asimov

enowned Science and

®M mm ®m®©o nu® r-i mmmrmmO©cl oooo®®®O®DDDDt0®®M©DDDD DDDmono

Today, Just '149 .95 Buys a Radio Shack TRS-80®Pocket Computer-And That's a Fact!

Back when computers filled entirerooms, Isaac Asimov was writingabout computers you could hold inyour hand. "Radio Shack's TRS-80Pocket Computer turned my dreamsinto reality. Now I can take the power ofa true computer with me wherever Igo," says Asimov .The TRS-80 Pocket Computer is programmable inBASIC. Isaac, however, would rather write novels thanprograms. "If you're like me, you'll want to get a lowcost interface that lets you use Radio Shack's ready-to-run programs." There are programs for engineering,finances, statistics-even real estate and aviation .

Rade IhaeKRetail prices may vary at individual stores and dealers .

The biggest name in little computers®

Programs and data stay in memoryeven when the Pocket Computer isturned off. And it can also function justlike a calculator-something adesktop computer can't do ."With a TRS-80 Pocket Computer, youcan hold the future in the palm of yourhand." Add our $79.95 Minisette°-9

cassette recorder and a Cassette Interface for $29 .95,or a Cassette Interface with built-in printer for$127 .95. They're all as close as your nearby RadioShack store, dealer or Computer Center .

I want a glimpse of the

Radio Shack, Dept. 82-A-502 ~future- send me a

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NAME

ADDRESS

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WORLD'S LARGEST SELLING ELECTRONICS MAGAZINE

JUNE 1982/$1 .25

How to Get Stereo Sound from TV&VCRsWireless System Stops Burglars BeforeThey EnterAdd a Status Monitor to Extension Telephones

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Copping Out

copout : to back out (as of an unwantedresponsibility) .

The Federal Communications Com-mission (FCC) recently declined to en-dorse any of the five AM stereo trans-mission methods submitted to it . TheCommision decided to allow the "mar-ketplace" to determine which system(s)it wishes to use .What a copout! To give you some

background: the FCC chose one stereoAM system (Magnavox's) in 1980, thensuccumbed to a cacophony of screechesand screams from a variety of disap-pointed contenders and others who fa-vored one system or another . So it didnot finalize its endorsement, intendingto study the proposals again . Now theFCC contends, in a 6-1 vote, that choos-ing a single system would cause furtherdelays in introducing stereo AM owingto fears of a lengthy court fight .What a copout!The one dissenter, Abbot Washburn,

notes that having competing systems outthere would result in higher receiverprices for consumers, who would have tobuy a receiver capable of tuning in the

Popular ElectronicsJog MEslcs

PublisherARTHUR P . SALSBERG

Editorial Director

DONALD MENNIEExecutive Editor

LESLIE SOLOMONTechnical DirectorJOHN R. RIGGSManaging Editor

EDWARD I.BUXBAUMArt Director

JOSEPH DESPOSITOTechnical Editor

DAVID M . WEBERFeatures EditorANDRE DUZANTTechnical IllustratorCARMEN ROBLESProduction EditorJEFF NEWMANEditorial Assistant

Contributing Editors:Walter Buchsbaum,

Len Feldman, Glenn Hauser, Julian Hirsch,Jim Keogh, Forrest Mims, Carl Warren

MARIE MAESTRIExecutive Assistant

CDflŒNL

various AM stereo systems that could beused in their reception area. He alsoobserved that this decision could delayAM stereo service (which has been onthe FCC agenda since 1977) .

A Commissioner who decided not todecide said that the action was "terriblyunfortunate." Another apologized bycalling the refusal " . . . a practicaland political solution to a technicalproblem ."I believe that the FCC has sullied

itself by not choosing a single, nation-wide system . This is carrying a free-market philosophy too far . Will the AMstereo broadcast maker who is bestfinanced overwhelm poorer competi-tors? Will the confusion of choosingfrom among multiple systems causebroadcasters to delay buying a transmit-ting system? Will radio receiver makersmove more cautiously in producing unitsto receive the mix of transmissions thatis likely to be chosen by various broad-casters?

According to the National Semicon-ductor Corporation, it has developed alow-cost AM stereo decoder chip that isuniversal to all AM stereo systems pro-

Editorial and Executive OfficesOne Park AvenueNew York, New York 10016212 725-3500

PublisherJoe E . Mesics212 725-3568

New York OfficeAdvertising Manager :Richard Govatski 212 725-7460Sales:Tom Ballou 212 725-3578Ken Lipka 212 725-3580

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Western RepresentativeNorman S . Schindler & Associates, Inc .7050 Owensmouth Ave ., #209Canoga Park, CA 91303 213 999-1414Sales : Norm Schindler, Jo Ann O'Hara

Representation In JapanJ . S . YagiIwai Trading Co ., Ltd .603 Ginza Sky Heights Bldg .18-13, Ginza 7-ChomeTokyo, Japan 104

posed. The pilot-tone section for eachsystem has to be added, though, as doswitching provisions. Since system com-patibility extends beyond different pilottones, I question whether performanceof each system would be optimized, pe-nalizing the consumer with less-than-the-best performance as well as higherprice .

The ultimate loser in this comedy isthe consumer, who will be forced toblithely switch his car stereo (estimatedto be the largest radio market for AMstereo) from one stereo AM system toanother as he rides merrily along a high-way. This would be a dangerous distrac-tion for any driver .

I hope that copping out won't becomethe order of the day for FCC decisions inthe future .

ABCMPA

Ziff-Davis Publishing CompanyRichard P . Friese

PresidentAlbert S . Traîna

President, ConsumerMagazine Division

Furman Hebb

Executive Vice PresidentPhillip T . Heffernan

Senior Vice PresidentsSidney HoltzEdward D . MuhlfeldPhilip SineRobert Bavier

Vice PresidentsBaird DavisGeorge MorrisseySelwyn Taubman

TreasurerBertram A. Abrams

Secretary

Editorial correspondence : POPULAR ELECTRONICS,I Park Ave., New York, NY 10016 . Editorial contributionsmust be accompanied by return postage and will be handledwith reasonable care; however, publisher assumes no re-sponsibility for return or safety of manuscripts, art work, ormodels submitted .

The publisher has no knowledge of any proprietary rightswhich will be violated by the making or using of any itemsdisclosed in this issue.

POPULAR ELECTRONICS