World Electronics i MARCH, 971 60 CENTS EW LAB TESTS VOLT -OHM -MILLIAMMETERS CATV -Its Future Starts Now COLOR TV FOR 1971 DIGITAL INSTRUMENTS -More on Electronic Counters EW Lab Tests NEW DOLBY-IZED CASSETTE DECKS 3`35'11:101-M4 1dl)10iÁ rin +056b 15 M NIZZOÓ566tiA3AdH N(lf %.(,' £pgÓ1108THIdO. www.americanradiohistory.com 1OW you can measure resistors accurately N CIRCUIT in solid state devices A A FE21 HI -LO with 41/2-inch meter $99.50 FE20 HI -LO with hi- voltage probe and large six -inch meter $129.50 WITH THE NEW HI -LO FIELD EFFECT MULI METERS USES ONLY .08 VOLTS TO POWER OHMMETER TO PREVENT TRANSI;TORw FROM CONDUCTING AND UPSETTING READINGS Look at these extra features to see why the Hi -Lo meter be'ongs on your want list: 9 DC current ranges from 100 microamps to 1 15 input Unbelievable specifications of megohm amp impedance on DC and 12 megohms on AC Automatic built -in battery test . ne,'Er a worry Laboratory accuracy of 1.5 percent on DC and about rundown batteries, just push the switches 3 percent on AC under the meter and read. as .1 full 9 DC voltage ranges from as low volts Standard .6 amp fuse to prote. t the ohms and scale to '000 volts milliamps scales if voltage or ove-load is ac- 3 hi- voltage ranges of 3 KV, 10 KV and 30 KV cidentally applied. No more nead to return the meter to factory for repair . just replace the 9 DC zero center ranges from .05 volts to 500 fuse. volts . a must for delicate transistor bias measurements Special probe with 100K isolatior -Esistor in probe to prevent AC pickup or tc prevent loading 7 resistance ranges from 1000 ohms ful scale to oscillator circuits. Leave in normal position for 1000 megohms most tests. Low voltage of .08 Here is why you volts prevents tran- should have both Hi Higher voltage of 1.5 from sistors conduct- and Lo battery volt- volts causes semi- ing and misreading conductors to con- circuit. Resistor will ages for correct in- duct ro rezd proper now read 10K as it circuit resistance front -to -back ratio or i should. Also prevents measurements in T condu:tivity of tran- any damage to tran- solid state circuits: sistors.. Meter would sistor. not be complete with- out hi -ohms reading. 1 v C CD 1=1 C INC. 3200 Senco:e Drive Sioux Falls, South Dakota 57107 CIRCLE NO. 123 ON READER '_ERVICE PAGE www.americanradiohistory.com Special introductory offer to new members of the ELECTRONICS AND CONTROL ENGINEERS' BOOK CLUB 404 437 A494, 754 SOURCEBOOK ENGINEERING OF ELECTRONIC MANUAL, 2/e CIRCUITS by R. H. Perry by J. Markus Pub. price, $12.50 Pub. price, $19.75 Club price, $10.65 Club price. $14.75 A523/401 CHARACTERIS- 570/426 TICS AND THE NEW OPERATION OF ELECTRONICS MOS FIELD - by B. Shore EFFECT DEVICES Pub. price, $10.00 by P. Richman Club price, $8.50 Pub. price, $10.00 Club price, $8.50 A037/604 507 A286 DIGITAL LOGIC SOLID -STATE AND COMPUTER ELECTRONICS OPERATIONS by R. G. Hibberd by Baron & Pub. price, $9.50 Piccirilli Special $1.00 bonus book Club price, $7.95 Pub. price, $14.50 comes to you with your Club price, $11.95 first club selection 0E37 377 350/434 092/32X TRANSISTOR 124/035 DIGITAL DIGITAL CIRCUIT HANDBOOK OF COMPUTER COMPUTER DESIGN PHYSICS, 2/e USER'S PRINCIPLES, 2/e HANDBOOK by Texas by Condon & Instruments, by Burroughs Odishaw by M. Klerer & Corp. C. A. Korn Inc., Staff Pub. price, $34.75 Pub. price, $9.95 Pub. price, $27.50 Club price, $14.95 Pub. price, $16.50 Club price, $8.45 Club price, $23.35 Club price, $13.95 A610/037 A259/607 COMMUNICA- A347 506 A565/031 MODERN COMMUNICA- TION SYSTEM ELECTRONIC AMPLIFIER TION ENGINEERING DIGITAL HANDBOOK TECHNIQUES PRINCIPLES HANDBOOK by R. F. Shea by P. M. Kintner by Stein & by Pub. price, $37.50 Jones D. H. Hamsher Pub, price, $12.50 Club price, $29.50 Club price, $10.65 Pub. price, $15.00 Pub. price, $29.50 Club price, $12.75 Club price, $24.95 MAIL THIS COUPON TODAY Save time and money by joining the Electronics and Control Engineers' Book Club ELECTRONICS AND CONTROL ENGINEERS' BOOK CLUB 582 Princeton Road, Hightstown, N.J. 08520 to meet your Please enroll me as a member of the Electronics and Control Engi- HERE is a professional club designed specifically neers' Book Club and send me the two books indicated below. I am day -to -day engineering needs by providing practical books to receive the bonus for just $1.03, and my first selection at the in your field on a regular basis at below publisher prices. special Club price shown. These books are to be shipped on ap- proval, and I may return them both without cost or further obliga- How the Club operates: Basic to the Club's service is its publi- tion. If I decide to keep the books, I agree to purchase as few cation, the Electronics and Control Engineers' Book Club as four additional books during the next two years at special Club Bulletin, which brings you news of books in your field. Sent to prices (approximately 15% below list). members without cost, it announces and describes in detail the Write Code No. of Write Code No. of Club's featured book of the month as well as alternate selections bonus book first selection which are available at special members' prices. here here When you want to examine the Club's feature of the month, you do nothing. The book will be mailed to you as a regular part of your Club service. If you prefer one of the alternate selec- tions -or if you want no book at all for that month -you notify Name the Club by returning the convenient card enclosed with each Bulletin. Address As a Club member, you agree only to the purchase of four City books over a two -year period. Considering the many books pub- lished annually in your field, there will sure:y be at least four State Zip that you would want to own anyway. By joining the Club, you E33155 save both money and the trouble of searching for the best books. J March, 1971 CIRCLE NO. 142 ON READER SERVICE PAGE 1 www.americanradiohistory.com r When you specify Mallory semiconduc- tors. It's always been the most dependable line ... for more of what you want. when There's you want it. And now there are more extras than ever before. For one thing, we've added items to make the selection better than ever ... from pre- tested multiple -cell rectifiers -such as the popular VB, CTN, FW, and FWL types -to a big hard -to -find items likeour2.5 amp rectifiers. Then there's performance - it's even higher than before. Our rectifiers have higher forward -current capacity and lower reverse leakage. And our Zener line has plus... 1 higher wattage ratings and sharper knee characteristics. And don't forget Mallory semiconductor prices: they're just about unbeatable .. take our focus rectifiers and epoxy case rectifiers, for example. So specify Mallory for silicon rectifiers, prepackaged rectifiers (voltage doublers, center -tapped full waves, full -wave bridges), color TV selenium rectifiers, Zener and dual- trigger diodes. Your Mallory distributor has them now. MALLORY DISTRIBUTOR PRODUCTS COMPANY MALLORY a divlelon of P. R. MALLORY & CO. INC. Box 1658, Indianapolis. Indiana -18206; Telephone: 317.636.5353 Batteries Capacitors Controls CRIME ALERT® DURATAPE ' Recorders Resistors Semiconductors SONALERT v: Switches Timers 2 CIRCLE NO. 134 ON READER SERVICE PAGE ELECTRONICS WORLD www.americanradiohistory.com Electronics World MARCH 1971 VOL. 85, NO. 3 Contents 25 EW Lab Tests New Dolby -ized Cassette Decks Julian D Hirsch ElectmnicsWorld 2e Triggering Logic Circuits James E. McAlister of simple circuits used to keep logic elements from being triggered ., because of contact bounce in relays, push- buttons, and toggle switches. 30 Recent Developments in Electronics 32 Digital Instruments Part 6. More About Electronic Counters THIS MONTH'S COVER EW Volt- Ohm -Milliammeters Julian D Hirsch shows the three new Dolby - 34 Lab Tests ized cassette decks that we --,Ay v ,611,y; tip. -u it cf II,.S. performance, and prices. Included are measurements on eighteen of newest models from half -dozen manufacturers tested and are reporting on in this issue. At the top left is the Harman -Kardon CAD -5; at the top right is the Fisher RC -80; and at the bottom right is the 3ç CATV -Its Future Starts Now WalterH Buchsbaum e over from on- the -air TV? Some answers Advent 200. Complete details ,r. -. installations in New York City and Akron.Ohio. on performance and prices will be found in our report on these three products. Pho- tograph by Dirone -Denner. 42 How to Locate Buried -Conductor Faults John T. Bailey Although the electronics man do, :Fly work with buried cables, he can use his knowledge of bridge circuits nu d c v.t.v.m.'s to find underground faults. 43 Color TV for 1971 (Part 2) Forest H. Belt 50 The "Perfect" Customer John Frye 6: Make Your Own Integrated- Circuit Modules Frank H. Tooker Publisher LAWRENCE SPORN 70 Solid -State Probe Thermometer cordon Gregg Editor WM. A. STOCKLIN Technical Editor 7 Reader Service Page MILTON S. SNITZER Managing Editor PRISCILLA B. HOEFER 12 EW Lab Tested Associate Editor Harm don "Citation 12" Stereo Amplifier MURRAY SUNTAG Advent ...Ivocate 101" Noise -Reduction Unit Contribution Fditors WALTER H.