Electronics Police /Emergency

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EGNSS X11-- -É HE SKIES ABOVE US S /E's roving report on what's what in outer space Dazzle your friends with lightworks.

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Sound too good to be true? We assure This course opens a tremendous future you it is all true, and you can prove it to for you. Full -time, part -time, your own busi- your own satisfaction within a few days! ness. You've got a whole new career to This course can stand up to any TV training gain- nothing to lose! at any price and you can get anywhere, Send the coupon- today! the cost is incredibly low. ICS, Scranton, Pa. 18515 National Electronic Associations agree. International Correspondence Schools so They found the ICS course so thorough, Division of Inte4 helpful, easy -to -grasp that they approved it for use in their own apprenticeship train- ICS, Scranton, Pa. 18515 Rush me free information on TV Servicing) t under- ing program! stand there is no obligation. There are six detailed self- teaching texts Name here, complete with illustrations and dia- (please print) grams. So effective, so practical, that when Address

you have completed the first two texts you City should be able to locate and repair 70 per- State Zip cent of all common TV troubles! Black and J8589H white, color.

OCTOBER- NOVEMBER, 1969 3 October /November 1969 Science and ec onlcs

SCIENCE SPECIALS * 44 The Skies Above Us-an introduction to prowling the galaxies 46 San Onofre's Fabulous 450-Southern California's unique, nuclear- powered generating station CONSTRUCTION PROJECTS * 35 Universal Darkroom Timer -an all- solid -state device that tunes prints and negatives with great accuracy and no moving parts * 41 Penny Pincher's Police Convertor -easy to build, low -cost convertor for listening to fire and police calls * 61 Sn /Fe Moving -Vane Ammeter-works on AC or DC * 67 97 -Cent Hard -Rock Fuzz Box -add fuzz to your amplified guitar * 79 Perpetual Motion Freq Standard -an electronic tuning fork SCIENCE AND ELECTRONICS FEATURES * 31 Light Powers This Liquid Semiconductor -experiment with the primitive photoelectric cell 73 Tallest Tower -newest design in self- supporting towers 78 Famous Patents- Marconi's four- circuit tuning patent COMM UNICATIONS- SWL /CB /HAM 49 Their Time Is Your Time -standard time stations 'round the world 56 Saturday Morning Ham -In- suburban Philadelphia hams at an early age 76 Ham Traffic -watch not, have not LAB CHECKS 59 Heathkit Model IG -28 Color Bar and Dot Generator 65 EICO Cortina Model 3150 Integrated Stereo Amplifier 71 Univox- Super-Fuzz Guitar Fuzzbox SCIENCE SHORTIES 30 The Precision Approach -cartoon page 40 Did You Know That . . .- keeping up to date on the latest happenings 60 Little Annie Fanny -broad view of computer drawing 82 TV's Long, Long Way to Tipperary REGULAR DEPARTMENTS 8 Stamp Shack-philatronics 10 Positive Feedback -a word from the boss 12 Bookmark -tome touting 14 New Products -gadgets and gimmicks 18 Ask Me Another -readers' Q & A 24 Literature Library-yours for two bits White's Radio Log, Vol. 51, Part 5 -page 83 Emergency Radio Services -Philadelphia Area -page 99 * Cover illustration by Len Goldberg Cover 00* Highlights ABC

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5 OCTOBER -NOVEMBER, 1969 NEW AND IMPORTANT and SAMS BOOKS Science ALL -NEW EDITION OF THE FAMOUS Electrbnics AUDIO CYCLOPEDIA Completely revised 2nd Edition -the most comprehen- sive reference now available on audio -by the renowned JULIAN M. SIENKIEWICZ, WA2CQL authority, Dr. Howard W. Tremaine. Fully covers every phase of the subject, including all the latest develop- Editor -in -Chief ments, right down to the newest solid -state and integrated circuits. Contains authoritative, concise explan- RICHARD A. FLANAGAN, KQD2566 ations of thousands of topics in the fields of acoustics, recording, and reproduction. Virtually a complete refer- Managing Editor ence library on the audio art in a single volume Order 20675, only $29.95 CHARLES S. HARRIS Technical Editor fr Transistor Substitution Handbook. New 9th Ed. Fully updated. Lists thousands of direct substitutions; HELEN PARKER, KQD7967 includes basing diagrams and polarity indications. Cov- ers manufacturers of all transistor types, providing sub- News Editor stitutions for U.S. and foreign home entertainment, industrial, and military types. Order 20705, only $1.95 JIM MEDLER Know Your VOM -VTVM. 2nd Ed. Art Editor Explains VOM's, VTVM's and solid -state electronic and Associate Art Director voltmeters in language anyone can understand. In- cludes full explanations of the circuitry, uses, care ARTHUR S. COOKFAIR; ERNEST A. KEHR; and repair of the instruments. Explains how to understand electrical measurements. Order 20676, on /y.$3.50 MARSHALL LINCOLN, K9KTL /W7DQS; 73 Dipole and Long -Wire Antennas ROY K. MARSHALL, PH.D.; JACK SCHMIDT Describes virtually every type of wire antenna; includes dimensions, configuration, and construction data for 73 Contributing Editors different types, plus appendices describing construction and operation of noise bridges and antenna line tuners, measuring data, etc. Order 65071, (Editors & Engineers) only $4.50 JOSEPH A. D'AMATO, Art Director Using and Understanding Unijunction Transistors IRVING BERNSTEIN, Cover Art Director Explains the construction, operation, and characteris- MARGARET R. GOTTLIEB, Art Associate tics of the unijunction transistor (UJT). Shows applications and circuits employing UJT's. Separate chapters JIM CAPPELLO, Advertising Director describe the use of UJT's as oscillators, voltage con- CARL BARTEE, Production Director trols, time delays and flashers, and in sensing circuits. Order 20720, only $2.50 GERTRUD BORCHARDT, Production Manager MARILYN VARGAS, Assistant Production Manager RTL Cookbook Explains the principles and use of RTL (Resistor -Tran- WILFRED M. BROWN, Instruments Division Manager sistor Logic) digital integrated circuits. Provides the experimenter with an understanding of RTL integrated circuits as they are used in everyday electronic projects. Shows how these circuits work and how to design B.G. DAVIS, Chairman of the Board with them. Order 20715, only $5.25 JOEL DAVIS, President and Publisher RECENT BESTSELLING BOOKS LEONARD F. PINTO, Tube Substitution Handbook. 12th Ed. 20700... .61.75 Vice -President and General Manager How to Build Speaker Enclosures. 20520 3 50 Citizens Band Radio Handbook. 3rd Ed. 20569....4.25 VICTOR C. STABILE, KBP0681, Color -TV Servicing Guide. 20358 4 25 Vice -President and Treasurer Tape Recorders -How They Work. 2nd Ed. 20445..4.50 ROGER G. CAVANAGH, How to Repair Major Appliances. 20650 4 95 Short -Wave Listener's Guide. 3rd Ed. 20695 2 25 Circulation and Marketing Director - -- HOWARD W. SAMS & CO., INC. - - AND ELECTRONICS I -- SCIENCE and RADIO - -TV EXPERIMENTER Vol. Order from any Electronic Parts Distributor, or 27, No. 21 is published bi- monthly by Science & Mechanics Publishing Co., a subsidiary of Davis Publications, Inc. Editorial, business, and mail to Howard W. Sams & Co., Inc., Dept. RT -10 subscription offices: 229 Park Avenue South, New York, N.Y. 10003. 4300 W. 62nd St., Indianapolis, Ind. 46268 One -year subscription six issues1- $4.00; two -year subscription 112 issuesl- $7.00; and three -year subscription 118 issuesl -$10.00. Add Send the following books: Nos $1.00 per year for postage outside the U.S.A. and Canada. Advertising offices: New York, 229 Park Avenue South, 212 -OR 3 -1300; Chicago; 520 N. Michigan Ave., 312 -527 -0330; Los Angeles: J. E. Publishers Rep. $ enclosed Co., 8380 Melrose Ave., 213- 653 -5841; Atlanta: Pirnie & Brown, 3108 Piedmont Rd., N.E.; 404-233.6729; Long Island: Len Osten, 9 Garden Send FREE 1969 Sams Book Catalog Street, Great Neck, N.Y., 516- 487 -3305; Southwestern advertising representative. Lim Wright, 4 N. 8th. St., St. louis, 314-CH -1 -1965. Name EDITORIAL CONTRIBUTIONS must be accompanied by return postage and will be handled with reasonable care; however, publisher assumes Address no responsibility for return or safety of manuscripts, art work, or photographs. All contr butions should be addressed to the Editor. SCIENCE AND ELECTRONICS and RADIO -TV EXPERIMENTER, 229 City State lip Park Avenue South, New York, N.Y. 10003. L Second class postage paid of New York, New York and at additional J mailing office. Copyright 1969 by Science and Mechanics Publishing Co.

6 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER KEEP PACE WITH SPACE AGE! SEE MOON SHOTS- LANDINGS, SPACE FLIGHTS, CLOSE -UP!.' }. BUYS:- ,1 "AMAZING SCIENCE for FUN, STUDY or PROFIT . .

iB SEE MUSIC IN DAZZLING ACTION Dramatic Breakthrough in MoSic 1Siold A COOL ADVENTURE WITH LIGHT! Audio -Visual Enjoyment SUPER 6" SPACE CONQUEROR ... The almost hypnotic spell of ever changing Actually see favorite mualcal selections trans- Superb Astronomical Reflector-Up to 576X. firelight has been captured in a cool -light lated into fantastic patterns of beautiful color Capable of revealing faint stars of nearly display box! With the liquid motions of -each individual note creating its own unique 13th magnitude, split double stars separated rising and cascading fountain blowing In the twisting, radiating shape . . each shape by less than I sec. of arc. Features alumi- wind, psychedelic colors appear, intermin- dancing and prancing, hirlins and swirling nized & overcoated 8" f/8 ground and pol- gle and vanish to rise again in new patterns in perfect time with the t1 . Easily at- ished pyrex parabolic mirror accurate to i/4 and drift away. This soothing light show tacked to stereo, radio, ta elrecorder. Send wave. 48 F.L. 8X achromatic finder scope. 4 housed In a handsome WA"A" square by 7" 25e in coin for 18 -page klet jt9098HP. eyepieces -48X Kellner, t/z" BOX & r/4" deep, walnut finished lumia light box is an Walnut Cabinet Model 192X Ramadens, Barlow to double or triple effective addition to any room -your living No. 85,1B1HP $99.50 F.O.B. power -rack & pinion focusing mount. 473/4" bedroom, rec -room, doctor's office. 71,030NP $45.00 Ppd. aluminum tube. Electric clock drive w /man- Especially effective among a wall picture 8" Set -No. vai slow- motion control. Setting circles. group. Modern as tomorrow -available today! 8" Do- lt-Yourself Kit Henvy.duty equatorial mount. Pedestal base. Stock No. 71,180HP No. 71009HP $22.50 Ppd. Compares to $295 -6350 models. Lassie Light Box Ppd. Stock No. 85,086H $239.50 F.O.B. $29.95 3" REFLECTOR TELESCOPE Stock No. 85,050HP $29.91 Ppd. Stock No. 85,105HP 41/4 " $98.50 F.O.B

BAROAINI LONG BLACK LIGHT FIXTURE NICKEL -CADMIUM BATTERY -WAVE Terrific lues --slightly used gov't surplus. Extremely versatile, compactly designed, long Lightweight Amp-hour bat- wave (3200 -4000 angstroms) black light tery with almost l'unlimited 41 e. pExtremely 'BRIGHT IDEAS' IN UNIQUE LIGHTING high current output. Recharges in 1 hour with Big, new 100 -page handbook packed with with built-in filter- eliminatee hrmfÌ shorten Edmund kit. Won't deteriorate when left dis- facie, loaded with illustrations. All latest wave ultraviolet rays. Use to identify min- charged. Minimum maintenance -few drops developments, applications, equipment. Cov- erals, fungi, bacteria -check for surface flaws, of water per year. Rugged, hock- and -vibra- ers trobes, sources, black light, projectors, oil and gee leakage-perfect for displays with nylon organic slides, color orgy mir- fluorescent paperpaper, paints, chalk. crayons. trace charged, filled h electrolyte.ve3t/' x2 "x6e. crystal and powder. Incl. aluminum reflector, 2 lb. rors polarized color, screens, light boxes. push -pull switch, connecting plug. Mount MusicVision, etc. Rare find for bulginess, vert., horr., or on corner. 10" L., 11/2" W., Stock No. 70,942HP (battery)...$15.00 Ppd. houses, No. 70,807HP (charger kit) $5.00 Ppd. bons..experimenters, [hobbyists. 1' c1í" 1t/z" H. Stock loot:eleaf paper punched to fit 3 ring binder Stock No. 70,304NP $12.50 Ppd. Stock No. 41,109EH (cell) $3.95 Ppd. add new developments as they happen. No. 00,124H (Replacement Bulb) $4.50 Ppd. Stock No. 9100HP $3.00 Ppd. GIANT FREE CATALOG

148 PAGES! MORE THAN 4,000 " UNUSUAL BARGAINS! Completely new 1969 edition. New items, categories. illustrations. Dozens of electrical and electromagnetic parts. accessories. Enormous selection of Astronomi- cal Telescopes, Micro- scopes, Binoculars. Magnifiers, Magnets. Lenses, Prisms. Many war surplus items: for hobbyists. experimenters. NEWI LOW -COST COLOR ORGAN workshop, factory. Mail coupon for catalog EDMUND SCIENTIFIC KITS Create tremendous variety of unusual and "HP." ASTRONOMICAL TELESCOPE beautiful effects. Simply plug In 3 dill. sets CO., 300 EDSCORP BUILDING, BAR - Grind your mirror for powerful tele- of colored lights and place near audio source. RINGTON, N.J. 08007 e stn pyrex mir- Notes picked up by interior "mike" deter- ror blank, tool, abrasives, diagonal mirror mine which colored lights go on- loudness and eyepiece lenses. You build instrument determines intensity. Surprising number of valued from up. commercial, display and home uses- control Name $75.00 lighting in pools and fountain., window and Stork No. Diam. Thickness Price holiday decorations, great for parties. Tough, 70,003HP 41/4" 3" $9.75 Ppd. compact with light intensity control. Address 70,004HP 1" 13.95 Ppd. x nit r ". 1 lb. 8 on. 8"0 1a/a" h Ppd. 70,005HP 21.00 Ppd. Stock No. 1900HP $39.95 State 7090811F 10" 1a/e" 34.25 F.O.B. 4 Channel De Luxe 2,000 Watt City Zip, 70.107HP 12íh" 21/a" 65.85 F.O.B. Stock No. 71,1031IP $195.00 Ppd.

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OCTOBER- NOVEMBER, 1969 7 tively, appreciated the potentials of INTELSAT. And almost as soon as its formation was announced, arrangements were made to link themselves into the American satellite program. They created "Telespazio" exclusively for this purpose under the aegis of the Italian Ministry of Posts and Telecommunications. By June, 1965, Telespazio was ready to make use of the first Early Bird facilities. Equipment which already is outmoded, was installed in a brand new, specifically designed center at Fu- cino, two miles from Avezzano, in Aquila Prov- ince, and once an important source of water in the days of Caesar and Claudius. As early as October of that year, Italian '1V viewers witnessed the arrival and all -day BY visit of Pope Paul VI to the UN, in New York ERNEST A. via satellite. KEHR As this communications medium was developed, Telespazio kept pace by acquiring and installing the The multi -color, 50 -lire stamp issued by costly equipment as it came from the manufacturers Italy on Nov. 25, 1968, is simply inscribed, here. And while the new antennae "Centro Telespaziale del Fucino." But the inter- now are in operation, still more recent equipment already is in continental communications progress it com- the process of being built, including a memorates is vastly more impressive. It was more sophisticated antenna that is 27.40 meters released to mark the opening of expanded fa- (90 feet) in diameter. cilities built by the Italian Government to take advantage of satellites for the intercontinental On Aug. 1, 1928, the Broadcasting Cor- transmission and reception of private messages, poration of China was established in Nanking, to radio and TV programs. The design shows the provide the populace with early radio news and Fucino installations, with one of two Space entertainment programs. To mark the 40th anniversary of antennae, each abòut 30 feet in diameter, in the that noteworthy event, the foreground. Chinese Postal Administration released 'a pair special Once the United States and the Soviet of postage stamps produced by the gov- Union rocketed sophisticated hardware into ernment's engraving plant in Taipeh. The $1 value outer Space, and proved satellites could be kept features a map of Asia with orbiting under meticulous control from ground concentric circles spreading all over the main- stations, this new communications technique was land from Formosa. All during World War II, adapted to commercial use to serve mankind. BCC fostered morale of both the armed forces In Washington, the initial efforts were cul- minated by the organization of INTELSAT, in February of 1965, to harness spacecraft potentials on a private basis. The peculiar ability of sending messages across vast distances not only relieved pressure on overloaded cables be- neath the seas; it enabled broadcasters to transmit instantaneous news events in a manner impossible through existing terrestrial equipment. ITALCABLE and RAI, Italy's two organizations concerned with private and commercial message China (Taiwan) 1968 Postal 40th Anni. transmission, and radio -TV productions respec- and the populace; it linked government agents in occupied areas, and conveyed China's voice to allied nations. After it moved to Taiwan in 1949, its facilities are being' used to transmit programs to the mainland of China, to keep the Chinese there constantly aware of what is hap- pening on Formosa. The $4 shows a small microphone from which an interesting pattern of red circles and Italy 1968 Fucino Installation (Continued on page 105)

8 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER The New f969 Improved Model 251 A REVOLUTIONARY NEW TUBE TESTING OUTFIT Tests all modern tubes including Novars, Nuvistors, Compactrons and Decals.

All Picture Tubes, Black and White and Color ANNOUNCING... for the first time A complete TV Tube Testing Outfit designed specifi tally to test all TV tubes, color as well as standard. Don't confuse the Model 257 picture tube accessory components with mass produced "picture tube adapters" designed to work in conjunction with all competitive tube testers. The basic Model 257 circuit was modified to work compatibly with our picture tube ac- COMPLETE WITH ALL cessories and those components are not sold by us to be used with other competitive tube testers or even ADAPTERS AND ACCESSORIES, tube testers previously produced by us. They were custom designed and produced to work specifically in NO 'EXTRAS" conjunction with the Model 257,

STANDARD TUBES: BLACK AND WHITE PICTURE TUBES: Single cable used for testing all Black and White Picture V Tests the new Novars, Nuvistors, 10 Pins, Magnovals, Tubes with deflection angles 50 to 114 degrees. Compactrons and Decals. The Model 257 tests all Black and White Picture Tubes More than 2,500 tube listings. for emission, inter -element shorts and leakage. 1/ Tests each section of multi -section tubes individually for shorts, leakage and Cathode emission. COLOR PICTURE TUBES: Ultra sensitive circuit will indicate leakage up to 5 Megohms. po The Red, Green and Blue Color guns are tested individ- Employs new improved 41/2" dual scale meter with a ually for cathode emission quality, and each gun is unique sealed damping chamber to assure accurate, tested separately for shorts or leakage between control vibration -less readings. grid, cathode and heater. Employment of a newly per- Complete set of tube straighteners mounted on front fected dual socket cable enables accomplishments of all panel. tests in the shortest possible time. The Model 257 is housed in a handsome, sturdy, portable case. Comes complete with all $4750 adapters and accessories, ready to plug in and use. No "extras" to buy. Only

We have been producing radio, TV and electronic test equipment since 1935, which means we were making of TV. The Tube Testers at a time when there were relatively few tubes on the market, 'way before the advent NOTICE model 257 employs every design improvement and every technique we have learned over an uninterrupted production period of 32 years. Accurate instrument Co., Inc. SEND NO MONEY WITH ORDER PAY POSTMAN NOTHING ON DELIVERY

ACCURATE INSTRUMENT CO., INC. Try it for 10 days before you buy. Dept. 671 2435 White Plains Road, Bronx, N. Y. 10467 If completely satisfied you may Please rush me one Model 257. If satisfactory I agree to remit $47.50 plus postage and handling charge. (If you prefer you may use our Easy Payment Plan.) If not postage and han- remit $47.50 plus satisfactory, I may return for cancellation of account. dling charge. (If you prefer you may Name use our Easy Payment Plan.) If not Address completely satisfied, return to us, City Zone State no explanation necessary. Save Money! Check here and enclose $47.50 with this coupon and we will pay all shipping and charges. You still retain the privilege of returning after 10 day trial for Lull refund.

OCTOBER- NOVEMBER, 1969 9 POSITIVE FEEDBACK

Julian M. Sienkiewicz t Fill in coupon for a FREE One Year Subscrip- EDITOR -IN -CHIEF tion to OLSON ELECTRONICS' Fantastic Value Packed Catalog- Unheard of LOW, LOW PRICES on Brand Name Speakers, Changers, Tubes, Tools, Stereo Amps, Tuners, CB, and other Val- Don't look now, but our new name-SCIENCE ues. Credit plan available. AND ELECTRONICS-appears on top of our old one ... and in larger type, too! Yep, we've made the switch. From here on in we can only go to bigger and better coverage of the exciting worlds of science and electronics. However, we If you have a friend interested in electronics send can't do the job alone. his name and address for a FREE subscription also. We need help from you! Look carefully at this issue and let us know what you think of it. Then, in a short letter, let us know exactly what you like and what you dislike. Tell us, too, what's missing so we can 480 S. Forge Street Akron, Ohio 44308 make our coverage more interesting and more complete. It's as difficult for an editor to judge his magazine as it is for an artist to judge his paintings. Keep (Could this explain why there are many starving artists and editors ?) So you see, by writing you up to date can get a better magazine and maybe make the Editor rich simultaneously (Wheel). Please ad- with dress all your remarks to The Editor, SCIENCE AND ELECTRONICS, 229 Park Avenue So., New SCIENCE & New York, N.Y. 10003. MECHANICS Plotl Programming a computer requires Science & Mechanics - translation of word or picture directions into the only magazine that numerical keeps you right up to a language understood by the com- date on developments puter's electronic circuits. Now, a new computer in space technology, accessory simplifies this translation by making weapons, automobiles, many programming tasks as easy as tracing lines medicine, boats, planes, on a blueprint or photograph. The accessory, a tools, new products, three -axis reversible scaler, was developed by . and exciting world The MicroMetric Corporation, Berkeley, Calif., events. a member of The Grass Valley Group, Inc. . Keep up to date. Make sure Designed for a wide range of industrial sci- of your home delivered copy and .- by returning the coupon today. entific applications, the new scaler will free programmers, now in short supply, from routine SCIENCE & MECHANICS SE -969 229 Park Ave. S., N. Y., N. Y. 10003 production and laboratory work, allowing them 12 issues $4; 24 issues $8; 36 issues $12. (Foreign: to concentrate on more profitable assignments. Add $1 a year.) Programming a computer to control a ma- Please enter my- year(s) subscription. chine tool, for example, can be accomplished D I enclose $ D Bill me. (No stamps) merely by tracing a blueprint of the desired Name part with the plotting cross hairs a - (Please Print) of Micro Address Metric two axis "digitizer," as the combination City State & Zip of the new scaler and its plotting table is called. (Continued on page 102)

10 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER Heathkif- Your Best Buy In Electronics

NEW Heathkit Solid -State Auto Tune -Up Meter ... NEW Voltage Measures Dwell, RPM And DC Kit ID -29 The new Heathkit ID -29 is most versatile ... really three automotive test instruments in one ... and its low price makes it even a better value. Measures $2995* Dwell on all 4 -cycle 3, 4, 6, or 8 cylinder engines ... measures RPM in two ranges 0 -1500 and 0 -4500 ... measures DC voltage from 0 to 15 volts. And no batteries are needed ... running engine provides both signal and power. Easy to use ... on both 6 and 12 volt system without changing leads. It's lightweight, has easy to carry ... comes equipped with black polypropylene case that a built -in lead storage compartment and is resistant to virtually everything. Fast, simple assembly ... takes just one evening. The perfect accessory for the handy- man who wants to do his own car tune-up, emergency road service personnel, or shop mechanics ... order your ID -29 now. 4 lbs.

NEW Heathkit GO-48 Solid -State Metal Locator A low cost, versatile, professional metal detector at one-third the cost of comparable detectors. Packed with, features for long life, rugged reliability, and 3 lbs. dozens of uses. Completely portable, battery operated and weighs only sensitivity The GD -48 is highly sensitive, probes to 6 feet, and has an adjustable NEW control. Its built -in speaker signals presence of metal; front panel meter gives Kit GD -48 visual indication. Other features include built -in headphone jack, telescoping in- shaft for height adjustment, smartly styled and smartly designed for easy $5995* or hand use and easy assembly. Whether you're an amateur weekend hobbyist a great help to a professional treasure hunter the GD -48 is for you ... also contractors, surveyors, Gas, Electric, Telephone and other public Utility Com- 2000 panies. 4 lbs. GDA -48 -1, 9 Volt Battery $1,30'; GD -396, Headphones, ohm (Superes) $3.50*

NEW Heathkit Electronic Metronome The new Heathkit TD -17 is a low cost, precise performing electronic Metro- NEW no springs nome.... a handy helper for any music student. Battery operated ... Kit TD -17 to wind ... accurate, steady calibration is always maintained ... from 40 to 210 beats per minute. Instruction label on bottom gives conversion from time $1295* signature and tempo to beats per minute. Stylish fruit wood finished cabinet. Easy solid state circuit board construction ... assembles and calibrates in only 2 -3 hours. The new Heathkit TD -17 Electronic Metronome is so low in cost every music student can afford one ... order yours now. I lb.

NEW Heathkit GR -88 Solid-State Portable VHF -FM Monitor Receiver Tunes both narrow and wide band signals between 152 -174 MHz . - . for police, fire, most any emergency service. Exceptional sensitivity and selectivity, will outperform other portable receivers. Features smart compact styling ... with durable brown leatherette case, fixed station capability with accessory AC power supply, variable tuning or single channel crystal control, collapsible whip antenna, adjustable squelch control and easy circuit board construction. The new GR -88 receiver is an added safety precaution every family should have ... order yours today. 5 lbs.

NEW Heathkit GR -98 Solid -State NEW -98 Portable Aircraft Monitor Receiver Kit GR Tunes 108 through 136 MHz for monitoring commercial and private aircraft broadcasts, airport control towers, and many other aircraft related signals. Has NEW all the same exceptional, high performance features as the GR -88 above. The Kit GR -88 $4995* perfect receiver for aviation enthusiast ... or anyone who wants to hear the panorama of America in flight. 5 lbs. GRA -88 -1, AC Power whole exciting each Supply 57.95

NEW Heathkit GD -28 8 -Track Cartridge Tape Player NEW The new GD -28 is an ideal addition to any home music system. Plays pre- Kit GD -28 recorded tapes through any system with a Tape Recorder, Tuner or Auxiliary input. Just push in the 8 -track stereo cartridge ... it starts and changes tracks $5995* automatically ... even shows which track is playing. Changes tracks instantly with the front panel switch too. Goes together quickly on one circuit board, and the famous Motorola® tape playing mechanism is preassembled & adjusted. At- tractive wood -grained polyurethane cabinet included. Order yours now. 10 lbs.

HEATH COMPANY, Dept. 19 -67 a Schlumaerpe suGa/diery Benton Harbor, Michigan 49022

FREE! Heathkit Catalog Enclosed is $ plus shipping. color. Fully de- Now with more kits, more Please send model (s) scribes these along with over 300 kits for Please send FREE Heath kit Catalog. Please send Credit Application. stereo /hi -fi, color TV, electronic organs, guitar amplifiers, amateur radio, marina, edu- Name cational. CB, home & hobby. Mail coupon or write Heath Company, Banton Harbor, Mich- Address igan 49022. City State Zip F.O.B. factory. Prices & specifications subject to change without notice, CL-360 L *Mail order prices;

11 OCTOBER- NOVEMBER, 1969 _525257_52 52 52.5?5252525252' Volume I, which concentrates on the basic hi -fi and stereo equipment, opens with a brief but very thorough discussion of acoustics. Writ- ten clearly, concisely, it gives the reader an excellent background, including the often over- looked relationship between enclosure, speaker BOOKMARK and listening area. Criteria are given for selecting the various BY BOOKWORM types of speakers. Cutting through the confusing array of enclosure types and sub -types the book tells just how different 52.5-65252525252.52 kinds of enclosures affect sound, and which kinds are particularly effective in given situa-

tions. Headphones, preamplifiers, amplifiers, (w m Here's Howl Don't take a back seat to any tuners and receivers are then discussed, showing one when it comes to shortwave and medium - wave DXing. The fifth edition of How To Listen To The World is now available and raising eye- brows of shortwave novices and pros alike. One of the main purposes of this book is to enable Volume I the listener (and TV viewer) to obtain the great- Soft cover est benefit from the world of radio through his 114 pages receiver. Radio world listening nowadays is no $3.25 longer a purely shortwave matter. Over the last few years, there has been an ever increasing interest in world listening on medium waves. Volume II Therefore, such Table of Content titles as "Im- Soft cover 104 pages $3.25

HOW TO LIS I tN TO THE WORLD a sampling of control features, connection pos- sibilities, and a comparison of the advantages and disadvantages of tube vs transistorized equipment. Volume II fully discusses record players and tape recorders, components which may be added to the basic hi -fi or stereo rig at any time. It shows Soft cover how different kinds of construction in 211 pages these components can affect performance. Cov- $3.95 ering phono arms, pick -up types, styli, etc., it gives concrete reasons why certain kinds of equipment should be selected or avoided. A proving medium -wave reception," "Medium- particularly valuable feature of Volume II is a wave propagation," and "Medium -wave DXing thorough troubleshooting guide. Here are 38 from Australia" offer a guide to the locked -in pages of tips on solid -state devices, tools, test- shortwave DXer who wants to switch to the ing, for those listeners who want to keep their lower frequencies. How To Listen To The equipment in top working order. World is edited by J. M. Frost and includes So pick up your copies of How to Select and articles from qualified authors, radio broadcast Use Hi -Fi and Stereo Equipment and get with organizations and DX -club officials. Get your good sound. Available at many electronic parts copy today direct from Gilfer Associates, Inc., stores or direct from the publisher, Hayden Box 239, Park Ridge, N. J. 07656. Book Company, Inc., 116 West 14th Street, New York, N. Y. 10011. m Takes Two for Stereo. How does the pros- pective buyer of hi -fi and stereo equipment spot L::, Ham Fact Dept. In the United States, any- those features which add up to the best possible one can get an amateur license -no prior elec- equipment in a particular price range and avoid tronics experience is necessary, and for the those which are well packaged, but low in Novice Class ticket, age is no barrier. Many quality? And how can the owner of a system youngsters under ten already have theirs, as improve his rig to gain increased listening well as a host of young -at -heart enthusiasts who pleasure? These are a few of the many ques- have begun to climb the ladder toward that tions answered in a practical two -volume paper- General, Advanced, or Extra Class License. To back set by the noted author Murray P. Rosen- pass the Novice Class exam only a "speaking thal. The volumes are titled How To Select and acquaintance" is required -the basic rules and Use Hi -Fi and Stereo Equipment. code. In effect now are new FCC rules intended

12 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER 3 SAW wives toward tNGN+tERi to encourage present radio amateurs i 41EtRflt+!t achievement of higher class licenses with reserved operating privileges and to stimulate interest among outsiders. A new book, Ham Radio Incentive Licensing Guide, tells how to begin, or to advance, to no each succeeding license class, in clear, concise, ,,;...a. and easy -to- understand terms. For many, the most formidable obstacle is learning the code. Here the reader will find proven methods of learning and developing proficiency with Inter- ne Creck° ïbrri l 2CrniCS' national Morse Code. An entire Chapter is MONPIPPItr#4tf ¢¢wa e the devoted to each license class, eliminating man whóknowg`_VICannICIäAS through material irrelevant necessity of wading TIME immediate goal, and if he is HOME SPARE for the reader's TRAIN AT and you pre. and income for a higher class ticket, he can simply present job booming Held! shooting Keep jobs in this Chapter. The Incentive pare for best pay skip to the appropriate IB Licensing Guide, prepared with the aid of the Climb up intop Electronics Tee CpS cialist! Computers, eommunl- EARN while you LEARN cations, alarm systems; 'hft- craft, space, machinery contt(tl A few months after APPROVED . these are just a few places Rom enrolling you can be Rado doing spare time you can fit into Electronic" Incentive Litwin. with a secure, top paying jo Guide Electronics repair jobs paying up to You enjoy reading about Elec- . . why make it *OW xw...rAw $25 to $35 for an tronics not evening's work! your career! We will train you as we have trained so many learn TO STEP INTO others. Earn while you PREPARE at home in spare hours. The JOBS LIKE THESE: I. T. I. practical, learn -by- Industrial Controls Maintenance doing method prepares you as Soft cover Your Own Electronics Service fast as you want to learn. Shop Closed Circuit T.V. In- Plan ahead for a big profit 160 pages stallation Servite Electronic business of your own or a good $3.95 Computer Maintenance Com- where the demand is so munications Aerospace Work job Automation Electronics Installa- great there just aren't enough tien ... and hundreds mor men to go around. actual test material, substantially well tell you about! If you enjoy working with FCC, includes your hands as well as your as it appears on official exam forms, and it mind, you can succeed in covers every question which may be encoun- LEARN Electronics with I. T. I. prac- BY DOING tical home study Training. tered in each test, from Novice to Extra Class. Your instructor works closely Build and keep vital Consul- Naturally, the text is authorized by a ham, Bert equip- with you. Unlimited electronics test tation Service. Easy I. T. I. Simon, W2UUN. To get your copy write to ment from big kits we to Work Sheets make learning the publisher, Tab Books, Blue Ridge Summit, supply. All yours fast and easy. Depend on use and keep! more than 40 year's experi- Pa. 17214. R ence. Find out free and without obligation what ELECTRONICS - f`,p Color Bench Rainbow. Here's a handy bench can do for you! mate for practicing color TV technicians and B &W experts who want to break into color TV servicing. It's On the Color TV Service Bench, MAIL COUPON FOR FREE BIG FACT BOOK Get big Free fact pack! See how you learn fast at home; start earning fast! Rush coupon today! I.T.I. APPROVED FOR TRAINING UNDER NEW G.I. BILL

MAIL COUPON FOR ELECTRONICS MONEY MAKING FACTS Industrial Training Institute, Dept. 65203 Soft cover 815 Rosecrans, Los Angeles, Calif. 90059 192 pages Rush me big FREE BOOK, "Get Into Big Pay $4.95 Electronics." Show how I can learn Electronics at home spare time guidebook writ- a brand -new troubleshooting Name ten by a real pro, Jay F. Shane, an expert who cut his teeth on the first TV circuits 20 years Address ago. The text describes causes and cures for City State Zip (Continued on page 105) jl. J

13 OCTOBER -NOVEMBER,, 1969 source is a 150 -watt tungsten- halogen lamp with an average rated life of 30 hours when NSW PRODVCTS operated in the Sun Gun system. The total Sun Gun unit will have a price of $119.95, including a custom -made carrying case. For more in- HIGH -FIDELITY formation write to Sylvania Electric Products AMATEVR RADIO Inc., 730 Third Ave., New York, N.Y. 10017. SHORT Beep -Beep! Beep -Beep! WAVE Do the kids bug you on road trips? Bell & Howell has devised the Road Runner cassette RECORDERS tape player kit to keep them off your back. Be- sides the Road Runner cassette, six batteries GIMMICKS and earphone, the kit contains two original tapes with stories, travel facts, behavior tips, GADGETS sing -along songs and games, all set to original TOOLS music. There's also a travel booklet and a spe-

i iSi11Gt1_lA.!Rg 11.70.. J) `; »s

Sun of a Gun! This new movie light unit from Sylvania is named the Sun Gun, is designed for 8 and 16 mm movie cameras, and operates on 9 nickel cadmium energy sources in a separate power pack that weighs only 3 lb. Each energy source has a running time of 10 minutes or approximately two 50 -ft. rolls of movie film when batteries are fully charged. The energy power Bell & Howell Road Runner Cassette Kit packs can be fully recharged in 60 minutes cial prerecorded cassette tape bonus offer. The with a separate recharger. The Sun Gun fea- package comes in a sturdy travel carton tures with a beam selector in the back of the light handle and sells for $38.88. If you head bought the so you can regulate the light beam from elements separately they would come to $45.00. spot to flood even when shooting. The total The Road Runner cassette features touch con- light output on the spot position is 15,000 cen- trol for fast forward, play or stop, easy drop -in ter beam candle power and 7,000 center beam cassette loading, and a rugged case. You can, candle power of at the flood position. The light course, use all standard cassette tapes in the Road Runner. At your local dealer or write to Bell & Howell, Video and Audio Products Div., 7235 N. Linder Ave., Skokie, III. 60076.

CB Base Station Antenna Avanti has a new CB base station antenna designed along the lines of antennas used to pinpoint signals on "moon bounce." There- fore, they have called it the Moonraker, and it combines 1/2 -wave cross dipole elements with Avanti's PDL design reflector. They include a switch box so you can have either horizontal or vertical operation. Moonraker's shorter boom length (15 ft.) helps keep weight and turning radius to a minimum and lets you use a standard inexpensive TV -type antenna rotor system. Also a plus from the shorter boom length is better signal excitation for greater Sylvania Sun Gun Movie Light Unit true gain -14.5 dB. Impedance is 50 ohms,

14 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER oaw...a lit1er way to drive and adiust hex socket screws ...IN PRECISION WORK screwdriver With the tools in this new, compact convertible in all set, you can turn all types of hex socket screws... types of locations ...faster, easier than with conventional keys. work Handy midgets are ideal for such delicate, precision as assembly and servicing of instruments and controls. Remarkable Moonraker CB Base Station Antenna Avanti "piggyback" torque amplifier handle adds grip, reach, and is power handling 1000 watts. Wind survival power needed for other is 24 90 mph, the weight of the Moonraker applications, lets you j lb., and the price is $129.95 with a one -year do more jobs with guarantee. Write to Avanti Research & Devel- fewer tools. opment, Inc.. 33 -35 W. Fullerton Ave., Addi- son, 111. 60101.

Skywatch by Ear Heath Company has ,a new portable aircraft monitor receiver, the GR -98, which tunes from 108 -136 MHz. With it you can hear commercial and private aircraft, airport control towers, PS -89 SET air control conversations, and many other air- 8 midgets (hex size .028" ver- craft- related signals. There's a six -to -one thru 1/8 ") plus hollow, nier tuning control, a built -in whip antenna, "piggyback" handle. Slim, trim, 40 -kHz selectivity and 1.5 -uV sensitivity for see -thru plastic case fits a 10 dB signal -to -noise ratio. Another feature pocket or tool box, is adjustable squelch control, and, for those doubles as bench stand.

-"N

ELECTRONIC O 0 o o 5V t PLY MART REQUEST COMPLETE HAND TOOL CATALOG which includes information on other Xcelite Compact Sets, too -slot tip /Phillips /Scrulox' screwdrivers, nutdrivers, and combinations. Nationwide availability through local distributor r-- -

XCELITE, INC., 64 Bank St., Orchard Park, N. Y. 14127 on Send complete tool catalog, which includes information all Xcelite Compact Sets.

name address city state & zip L In Canada contact Charles W. Pointon, Ltd.

15 OCTOBER- NOVEMBER, 1969 NEW PRODUCTS

one of the nicer features of the Magni -Fi is its very low price: $7.95. If desired, a 3- diopter lens is available for $2.98. Magni -Fi is available by mail (35e postage) from Nel -King Products, Inc., 811 Wyandotte St., Kansas City, Mo. 64105.

Grownup Erector Set Dexion Inc.'s slotted steel angle is now available at your local lumber yards, hardware, and department stores. Framework for work- benches, machine stands, shelving, soap box racers, and lots of other items can be assembled just like you did with your Erector set. All you need is a wrench and a hacksaw. Dexion angle

Heathkit GR -98 Aircraft Monitor Receiver

who want to monitor one station almost continuously, the GR -98 has crystal control of one- channel -just plug in the crystal of your choice, tune to the approximate frequency and flip the front panel switch to the Xtal position and you're on frequency immediately. GR -98 weighs less than 4 lb. with six C cells installed, and measures 711 x 811 x 311 -in. For fixed station use, the carrying handle converts into a tilt stand and an external antenna jack is provided. The tuner portion is factory assembled and aligned; the rest goes together on a single circuit board. Price: $49.95. For more details write Heath Co., Benton Harbor, Mich. 49022.

Hobbyists, Stop Squinting! Having trouble making out details on those printed circuits? The Magni -Fi has a headband that adjusts to any head size and a precision Dexion Slotted Steel Angle 21/2 diopter lens. It not only leaves your hands free to work, but the hinged lens swings up and is made of cold rolled steel with a baked enamel finish. out of the way when you don't need it. You can It's packaged in bundles of 8 five - wear Magni-Fi without or with glasses. And foot lengths with nuts, bolts and corner braces included. This is called the Dexion 100 kit and its price is $12.65. Write for their Idea Pamphlet, which illustrates 21 do- it- yourself projects -from storage units to pet stands and puppet theatres. For a free copy send to Dexion Inc., 39 -27 59th St., Woodside, N.Y. 11377.

New Sound 'N Color Family A whole new dimension for your music - color! EICO has three new models in their Sound 'N Color line which use special low - voltage, high- intensity lights to achieve their startling effects. The light boxes come in three and four channel models-each channel Nel -King Magni -Fi re- sponding to a different portion of the audio spectrum. Every combination of musical in-

16 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER ERSIN MULTILORE 5 -CORE

Model 3440 Model 3445 Model 3450 SOLDER EICO Sound 'N Color Organs struments produces its own distinct multi -color pattern. Shown are Model 3440, 3- channel, 15 x 10 x 6 -in., in kit form $49.95, wired $79.95. Next is Model 3445, 4- channel, 24 x 12 x 10 -in., kit $64.95, wired $99.95. The one on the right is the jumbo model, 3450, 4 channels, 30 x 15 x 11 -in., kit $79.95, wired $109.95. For more only 690 info, write EICO Electronic Instrument Co., Inc., 283 Malta St., Brooklyn, N.Y. 11207. BUY IT AT RADIO -TV PARTS STORES Clear the Tracks for Stereo! The new Heathkit GD -28 is a stereo tape player kit designed to play back prerecorded MCILTICOli SALES CORP., WESTBURY, N.Y. 11591 ¡ 8 -track stereo tape cartridges through any home automatic; music system. Unit is completely Catalog FfNESTVGOV plugs in the cartridge of his choice. FREE the user just SURPLUS ELECTRONIC BARGAINS A metal tape splice switches the play -head from one track to the next automatically, or you can Now BIGGER and select the track you want by pushing the slide - BETTER Than Ever! switch on the front panel. Pilot lamps indicate which track is playing. The tape player mecha- -_. MAIL THIS COUPON NOW --' nism is preassembled and adjusted, and the 6- transistor, 2 -diode preamplifier circuit goes NAME one small circuit board. together in a trice on I ADDRESS: I (Continued on page 106) LCITY' STATE: ZIP: I

For your FREE copy, fill out coupon and mall. Dept. TV FAIR RADIO SALES 1016 E. EUREKA Box 1105 LIMA, OHIO 45802

NOW IFOR M c G E E' S

SENT1 FREE9 CATALOG 1001 BARGAINS IN SPEAKERS -PARTS -TUBES -HIGH FIDELITY COMPONENTS -RECORD CHANGERS - TAPE RECORDERS -KITS- EVERYTHING IN ELECTRONICS McGEE RADIO CO., 1901 McGee Sf. IRTE) Kansas City, Missouri 64108 SEND 1969 McGEE CATALOG NAME being replaced "Sorry, Higgins, you're ADDRESS but not exactly by a computer." CITY STATE ZIP

17 OCTOBER -NOVEMBER, 1969 sAt**iY**** ;; ***************************************Id

the voltage is too low. Do 1 have to add an AC input voltage control? -A. M., Santa Barbara, Calif.

ORIGINAL

ME ANOTHER ASK FROM EXPERIMENTER RECTIFIER OUTPUT RADIO -TV SOUTH 229 PARK AVENUE NEW N. YORK, .4(

MODIFIED

It's Zapped! Everytime my amplifier is turned on, the 6X5 rectifier tube burns out. What gives? -R. L. F., Middletown, N. Y. Undoubtedly the input filter capacitor (see diagram) is shorted. Replace it with one of the Try a resistor in series with input capacitor same value in microfarads. The same trouble Cl. Try various values until the output voltage is correct. The resistor will probably have to be a wire wound type rated at 10 watts or more.

6X5 Old Waves 8+ What was the first broadcasting station in the U.S.? Both FILTER KDKA in Pittsburgh and WW1 in CAPACITOR Detroit claim the title. Also, was it 1920 or 1921? -D. H., Metairie, La. The way we heard it, it was KQW in San Jose in 1913. Before that DeForest broadcast live opera in New York. And before that it was just ghosts in the attic. occurs in solid -state diode rectifier circuits only there's a very low ohmic resistor between Point of Information the diode and the filter capacitor that overheats In reply to E. E. C., Jr., of New Bern, N. C. and pops. Replace filter, capacitor, resistor and on where to obtain the light emitting diode for diode. the "Talk on an Infrared Light Beam," they are obtainable from Cleveland Service District, Never!! Lamp Division, General Electric Co., 12910 Taft Avenue, Cleveland, Can you give me a schematic of a solid - Ohio 44108. Request state phono preamplifier? an SSL -4 solid state lamp. The cost is under $10.00. (Our thanks go to -C. R. B., Amityville, N. Y. G. H. of Dickinson, N. D. Why? There are several good wired units for the info.) available on printed circuit boards and modules that are a heck of a lot cheaper than the parts DX for UX199 needed to make one. Look through the cata- 1 have an old RCA Radiola 20 which uses logs of Lafayette Radio, Allied Radio, and type UX199 tubes. Where can 1 get replace- Radio Shack for some good buys. ment tubes? Our local stores don't have them. -L. J. E., Everett, Wash. Get information on the phone by dialing Show Some Resistance 206 -MA 4 -2341 or order direct by mail from 1 am having trouble getting the right voltage Seattle Radio Supply, 2117 Second Avenue, out of a DC power supply. When 1 use a ca- Seattle, Wash. 98121. The Company advertises pacitor input circuit, the voltage is too high. that they have lots of old tubes (199, 12A, 483, When 1 disconnect the input filter capacitor, etc.) and sell them at $3.00 each.

18 .SCIENCE A ND ELECTRONICS, formerly RADIO -TV EXPERIMENTER THOUSANDS OF BARGAINS TOP VALUES IN ELPART°SNIC Achtung! -FI, new Grundig radio Transistors, Modules, C. B., Speaker, Stereo, HI 1 have seen a relatively and Thousands of Other Electronic Parts. got it out-of- Photo Cells in a local drug store. The owner Send for FREE Catalogue state from a fellow who needed the money. DISTRIBUTORS INC. Whom can I contact to obtain Grundig sales ELECTRONIC information? I am interested in AM and FM stereo plus short wave reception. EDI -R. B. V., Montgomery, Ala. Dept. TA -2, 4900 Elston Sales, 355 Lex- Chicago, III. 60630 Write to Grundig Electronic RUSH CATALOGUE ington Avenue, New York City. Name Address City Going Abroad State Zip Code In recent months I have obtained quite a few to 2S transistors. I hare found no reference and would TREASURE such types in magazines or books silver, with Find buried gold, like to know if they are interchangeable coins, treasures. please give me (or the same as) 2Ns. If not, 5 Powerful models. some information on them. Write for free catalog -D. S., Liberty, Mo. 95 Refer- DEPT. Get a copy of the Datadex Transistor RELCO C -58 ' UP from IRC. Inc., 401 N. 11018 ence Book for $3.95 BOX 10839, HOUSTON, TEX. Broad St., Philadelphia, Pa. 19108. It lists 2S and their 2N or other equivalents. numbers TUBES! CORNEI TUBES! Fgef Juvenile Send For çper Amateur CORNELL'S c 33 tube am not old enough to have a CB license. But 34:)tpuer I New 1969 WE SELL have heard that it does not matter what your be I CATALOG PICTURE is for ham license. Is this true? OF 100 age Many New Items IN LOTS TUBES S., Brookfield, Mo. -D. L. 92105 4219 E UNIVERSITY AVE., SAN DIEGO, CALIF. Wish I had your problem. Yes, it's true. If you can pass the test. Start studying. A sensible way to protect your copies of Back to School (and preserve) SCIENCE AND ELECTRONICS 1 next to nothing about radio or elec- know formerly tronics, but would like to learn. I saw an ad in RADIO -TV EXPERIMENTER your magazine on kits. Would I be able to gain enough basic knowledge from assembling these

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A durable, custom-designed Library Case will protect your copies of SCIENCE AND ELECTRONICS from dust and wear. At the same time, it will help you conserve valuable space and reduce library clutter. Each Library Case has a muscular 9 "x63/y "x4%" frame that can hold 12 issues of SCIENCE AND ELECTRONICS. In elegant washable Blue simulated leather, its spine is embossed with 16 -k gold lettering for maximum legibil- ity. (Each Library Case also includes gold transfer so you can print the volume and year each case contains.) To order, merely fill in and return the form below. To: JESSE JONES BOX CORP. 19141 P. 0. Box 5120 - Dept. D - Philadelphia, Pa. Please send me SCIENCE AND ELECTRONICS Library Cases at $3.50 each.° I understand this price includes postage, packing and handling. (e 3 Library Cases for for $10.00, 6 for $19.00.) My check (or money order) C is enclosed. NAME (PLEASE. PRINT) ADDRESS "A cable from Uncle Willie? I didn't CITY STATE ZIP know he went abroad!" Note: Satisfaction guaranteed or money refunded. Allow 3 weeks for delivery.

19 OCTOBER- NOVEMBER, 1969 ASK ME ANOTHER ** *r* r*** *r*** ******* * *** * * ****** * ** kits to go on to more advanced projects, or with a voltage drop of less than a volt across would I be better ofj to start out some other the diode. way? Connect a DC voltmeter across D and try -S. G. K., Wichita, Kansas various values of R (during no- signal condi- Building kits is a good way to get some prac- tion) so that the diode will not be forward - tical experience. But, take a home -study course biased and therefore conduct. For C2, use a or go to a resident school to learn theory and high value electrolytic. If ungrounded output to get guidance. There's nothing like school for is positive instead of negative, reverse the po- learning. larity of the diode and of C2.

Museum Piece Socket to Me I recently acquired an old Burndept SW /BCB 1 read somewhere that it is possible to pep receiver and a set of 26 plug -in coils. It will up a receiver by replacing the RF amplifier cover 11.8 to 520 meters, but it uses three Burn - with a tube of higher gain. 1 decided dept Super- Valves in place of tubes. I wonder to do this with my if you could tell me its age and approximate Lafayette HA -63. 1 replaced the value. It works and is in fairly good condition. 6BA6 with a 6GM6 (making all socket -F. W., Kamloops, B.C. changes). Now my "S" meter no longer The Super- Valves are undoubtedly tubes with works, there's no increase in sensitivity, but a glamorous name. Vintage should be around there is some distortion. Can you tell me 1929; value about one buck. The Edison Mu- what I did wrong and possibly how to cor- seum in Greenfield Village, Dearborn, Michigan, rect it. would probably like to have it. -P. A. J., Maspeth, N.Y. The two tubes have somewhat Way Out different characteristics. Make sure you wired socket 1 need some advice about protecting my short- terminals 2 and 7 together! In general, it's wave antenna from lightning. 1 have been told better not to tamper with a receiver. The to use a lightning arrestor. 1 have also been told man who designed it obviously not to use one, because it could had good rea- very well attract sons for selecting lightning. What should 1 do? the tubes he did; there is only -C. L., Fredericksburg, Va. a small difference in price between these Use a lightning arrestor. But install it prop- two types. Gain is usually dependent on erly, or you'll be exactly where you started, overall circuit design and the parameters with no protection at all. given in tube manuals should not be taken too literally. Do Hum In Between musical passages there is an annoy- Long Story on Long Wire ing hum in the speaker which is fed by a tran- I am using a Hallicraf ters S -120 to listen to sistorized amplifier employing a Class B out- the BCB. Sensitivity on the BCB is good with put stage. 1 don't notice the hum when music just the ferrite bar antenna. However, being a is played. How can 1 stop the hum? DX hound, I would like to use a better an- -D. E. R., Holywood, Calif.

-----.1110 . R u VW TO RECTIFIER AMPLIFIER T' T2

You might try adding additional power supply filtering by adding capacitor C2, diode D and resistor R, as shown in the diagram. Ca- pacitor CI is the existing output filter capacitor. When there is no audio signal going through the amplifier, power supply current is low, the diode does not conduct, and filter section R /C2 reduces power supply ripple. When power supply current rises, the diode conducts, "I rather fight than switch!" shorting R, and allowing heavy current to flow

20 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER What good are clean ash trays when you can't get the car the ash trays come in even when you have a reservation and the reservation has been confirmed?

For a long time now, there's been so little difference between car rental companies they argued publicly about who had the cleanest ash trays. Max has changed all that. Max is National Car's computer. He knows from minute to minute which of our cars are available. Wherever you are, anytime of the day or night, you can call National for a reservation toll -free at 800 -328 -4567. And thanks to Max, we don't have to make any assumptions or blind promises like those New York outfits do. We just ask Max what's available, Max tells us, and we can guarantee you a car on the spot. National also. features GM cars, gives S &H Green Stamps, and has 1800 locations. Second only to old what's -its -name. Now there are some differences you can sink your credit card into -any recognized credit card. NATIONAL CAR RENTAL

ÌI `"---- o Not.ConRant-Co 1969 thoughoo the world it's TIIDENiaterNATIONAI We make the customer No. 1 Conoda and

21 OCTOBER -NOVEMBER. 1969 ASK ME ANOTHER ****************Itrtrtr tenna like the 75 -foot long wire in my attic which I use for SW. This is my problem. How do 1 go about coupling the antenna to the ust S -120? I've tried connecting it to the antenna about everybody dabbles terminal on the back, but the results were very in electronics! poor. The antenna boosted signals, but 1 got hets, a high- pitched tone, and strong locals all Why over the band. Also, when 1 tune in a strong not you? local (on the right frequency) the audio is very distorted. Connecting the antenna to the ferrite bar antenna netted me the same results. How can I couple the antenna to the S -120 so that it works for BCB? Also, how can I eliminate the ferrite bar antenna completely, and just use the antenna? -W. W., Chicago, Ill.

121E6 CONVERTER

There's one magazine L5 that'll put you in orbit. eiementarr X TO -- IANO SWITCH TO Electronics ANTENNA TERMINAL Here's a magazine that serves up elec- Your receiver's schematic diagram shows tronic theory in pleasant spoonfuls that when an external antenna is connected to the antenna and terminal the long wire ant signal reinforces the knowledge you is fed to a tap on the internal ferrite antenna, gain with exciting and useful projects which is as it should be. In Chicago, in the you can build at home today! This proximity of lots of high power radio signals, you can expect the problems fine you encountered. magazine will be delivered to There's just too much signal being pumped into your mailbox at the special rate of the receiver input. You could try adding a manual RF gain just $3.00 for six issues. Order now! /level control, as shown in the simplified diagram. Break the circuit at "X" and connect a 5000 -ohm pot and an 0.1 µF capaci- ELEMENTARY tor as shown by dotted lines. ELECTRONICS Dept. 113 229 Park Ave., South, New York, N.Y. 10003 He Gets the Image Begin my subscription to ELEMENTARY ELECTRONICS My small, portable eight- transistor at your special low-subscription radio rate of $3.00. picks up CW signals on 930 kHz and at (Outside USA & Canada, add $1.00 for postage & handling) about 690 kHz when I'm at Newport Beach. Bill me Money enclosed With my communications (No stamps please) receiver operating in the 200-400 kHz band, I hear CW signals Name exactly the same as on the BCB except that (please pnat) they are much stronger. Could you please Address explain this? -L. C. Tucson, Ariz. i City State lip It could be that the signals from the CW station are being heterodyned with a signal 22 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER from a strong BCB station. For example, if Not all good things a CW signal on 290 kHz beats with a BCB station on 640 kHz their sum frequency would be 930 kHz. You would hear the CW disappear... signal as an audio tone since the sum frequency and the carrier of the BCB station on 930 kHz would not be exactly the same. Also, the 290 -kHz signal beating with a 980 - kHz BCB signal would produce a beat at 690 kHz. These may no be the actual conditions that existed when you heard the CW signals, but the principles are the same. The CW signals could have come from a beacon, Naval, or commercial shore station, or from a nearby ship. These signals will produce a beat if the first stage of your receiver is non- linear- which would be the case if it has no RF stage Though Radio -TV Experimenter -the old- ahead of it. If it has one, the RF stage est name on the newsstands for a small - could be overloading or be biased improper- size electronics magazine -is passing ly for linear operation. into history like the 5c beer, its new name, SCIENCE AND ELECTRONICS, will continue to serve its readers in the spirit and Cheapy Q Checker tradition of the old. The only test equipment I have is a VOM. Any dramatic changes? Not really, for you How can ! test the transistors in my radio see the editorial coverage for Radio -TV with it? Experimenter has been science and elec- -T. I., Duluth, Minn. tronics for several years. the VOM Look for a bright new future with SCIENCE Connect the negative lead of with its new collector of AND ELECTRONICS, for (set to measure DC volts) to the descriptive name many new readers in- to its a pnp transistor and the positive lead terested in the varied esoteric corners of emitter. If it is an npn transistor, the VOM electronics and science will join our ranks. leads should be just the reverse. Finally, use And with greater numbers, the Editors of a clip lead and short the base to the emitter. SCIENCE AND ELECTRONICS can serve If the voltage increases, the transistor is ac- you better. There'll be bigger and better for tive and you're in business. But, let's be hon- stories; varied construction projects home, and lab; fun items just for est need a transistor tester. hobby, -you relaxing. Look for it on your newsstand or, better yet, enter your subscription now. r Mail today to Dept. 114

Science and 'Electronics 229 Park Ave. So., New York, N.Y. 10003 You keep the beer -send to me my copies of Science and Electronics regularly. I understand the price is only $3.00 for six issues -a great buy! Scratch Enclosed (no stamps) Bill mel Name Address City State Zip "Actually it's very practical!" Outside USA and Canada -add $1.00 :,,,,,,,,,.1,...1...,.,..1.,.,,,11111,111,1,.1.,.,,....,.111,1,,,,...,.....».,.,...11 ...... ,.,,,,,,,1,.,,.,,,,,,,,,,,,,,,,,,

23 OCTOBER -NOVEMBER, 1969 LITERATURE

11111111111111 10. Bursteln- Applebee offers a new 116. Pep-up your CB rig's perform- giant catalog containing 100s of big ance with Turner's M +2 mobile mi- pages crammed with savings includ- crophone. Get complete spec sheets ing hundreds of bargains on hi -fi kits, and data on other Turner mikes. power tools, tubes, and parts. 48. Hy- Gain's new CB antenna cata- *11. Now available from EDI (Elec- log is packed full of useful informa- tronic Distributors, Inc.): a catalog tion containing and product data that every hundreds of electronic CBer should know. Get a copy. items. ED! will be happy to place you on their mailing list. 111. Get the scoop on Versa- Tronics' Versa -Tenna with instant magnetic *6. Bargains galore, that's what's in store! mounting. Antenna models available Poly -Paks Co. will send you for CBers, hams and mobile °nits their latest 8 -page flyer chock -full of from 27 MHz to 1000 MHz. Poly -Paks' new $1.00 electronic and scientific "blis -dor" paks and equipment. 45. CBers, Hams, $WLs -get your copy of World Radio Labs' 1969 catalog. If you're a wireless nut or ex- 23. No electronics bargain hunter perimenter, you'll take to this should be caught without the 1969 catalog. copy of Radio Shack's catalog. Some equipment and kit offers are so low, *101. If it's a CB product, chances they look like misprints. Buying is are International Crystal has it listed believing. in their colorful catalog. Whether kit or wired, accessory or test gear, this CB- oriented company can be relied CB-- AMATEUR RADIO on to fill the bill. ELECTRONIC PARTS SHORTWAVE RADIO 103. Squires- Sanders would like you *2. Now, get the all -new 512 -page, 102. No never mind what brand to know about their CB transceivers, fully illustrated your CB set is. Sentry has the "23'er" and the new "SSS." Also, Lafayette Radio 1969 the crystal CB catalog. Discover the latest in CB you need. Same goes for ham rigs. accessories that add versatility to gear, test equipment, ham gear, tools, Seeing is believing, so get Sentry's their 5- watters. books, hi -fi components and gifts. catalog today. Circle 102. Do it now! 146. It may be the first -Gil /er's spe- TOOLS Edmund *5. Scientific's new cata- ciality catalog catering to the SWL. Xcelite's midget log contains over 4000 products that Books, rigs, what -nots-everything you *78. hex socket embrace many interests and screwdrivers in Xcelite's PS -89 set fields. It's need for your listening post. Go Gilfer, let you make delicate a 148 -page buyers' guide for Science circle 1461 adjustments Fair fans. easier. "Piggyback" handle adds grip, reach, and power needed for other 0/son's 100. You can get increased CB jobs. *4. catalog is a multi -colored range and clarity using the "Cobra- newspaper that's packed with more 23" transceiver with speech compres- bargains than a phone book has sor- receiver sensitivity is excellent. 118. Secure coax cables, speaker names. Don't believe us? Get a copy. Catalog sheet will be mailed by B &K wires, phone wires, etc., with Arrow Division of Dynascan Corporation. staple gun tackers. 3 models for wires *1. Allied's catalog is so widely used and cables from dho" to th" dia. Get as a reference book that it's regarded 141. Newly- designed CB fact-full Arrow literature. as a standard by people in the elec- antenna tronics catalog by Antenna Specialists has industry. Don't you have the been sectionalized to facilitate the 1969 Allied Radio catalog? The sur- picking of an antenna ELECTRONIC PRODUCTS prising thing is that it's free! or accessory from a handy index system. Man, 143. Bring new life to your hobby. *7. Before you build from scratch, Antenna Specialists makes the pickin' Exciting plans for new projects -let check the Fair Radio Sales latest cat- easy. Electronics Hobby Shop give you the alog for electronic gear that can be dope. Circle 143, now. modified to your needs. Fair way to 130. Bone up on the CB with the save cash, latest Sams books. Titles range from "ABC's Radio" *44. Kit builder? Like wired prod- of CB to "99 Ways ucts? EICO's 1969 catalog takes care 8. Get it now! John Meshna, Jr.'s to Improve your CB Radie." So Cir- cle 130 and get the facts of both breeds of buyers. 32 pages new 96 -page catalog is jam packed from Sams. full of hi -fi, test, CB, ham, SWL, au- with surplus buys -surplus radios, tomotive and hobby kits and products new parts, computer parts, etc. 107. Want a deluxe CB base station? Then get the specs on Tram's -do you have a copy? *140. How cheap is cheap? Well, all new Titan I1 -it's the SSB /AM rig take a gander at Cornell Electronics' you've been waiting for! *42. Here's colorful 116 page catalog latest catalog. It's packed with bar- containing a wide assortment of elec- copy E. tronic kits. You'll find something for gains like 6W4, I2AX7, 5U4, etc., 96. Get your of F. John- budget. tubes for only 33e. You've got to see son's new booklet, "Can Johnson 2- any interest, any And Heath this one to believe it! Way Radio Help Me ?" Aimed for Co. will happily send you a copy. business use, the booklet is useful to *135. Get with ICs! RCA's new everyone. 144. Hear today the organ with the integrated Circuit Experimenter's Kit "Sound -of- Tomorrow," the Melo- KD2112 is the first of its kind and 129. Boy, oh boy -if you want to Sonic by Whippany Electronics. It's should be a part of your next project. read about a flock of CB winners, get portable -take it anywhere. Send for Get all the facts direct from RCA. your hands on Lafayette's new 1969 pics and descriptive literature. Circle 135. catalog. Lafayette has CB sets for all pocketbooks. 12. C. B. Hanson new Automatic 106. With 70 million TV and 240 Control records both sides of a tele- million radios somebody somewhere 46. Pick up Hallicrafters' new four - phone call automatically -turns off will need a vacuum tube replacement page illustrated brochure describing automatically, too! Get all the details at the rate of one a second! Get Hallicrafters' line of monitor receivers -today! Universal Tube Co.'s Troubleshooting -police, fire, ambulance, emergency, Chart and facts on their $1.50 flat weather, business radio, all yours at 126. Did you dig Delta's new litera- rate per tube. the flip of a dial. ture package chucked full of pics and

24 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER * Starred items indicate ad- vertisers in this issue. Consult their ads for additional in- LIBRARY... formation and specifications.

specs on such goodies as an FET- 114. Prepare for tomorrow by 1969 stereo consoles. Discover how to VOM, SCR ignition system, compu- studying at home with Technical pick a hi -fi console for your living terized auto tach, hi- voltage analyzer, Training International. Get the facts room. etc.? Man, then let Delta know you're today on how you can step up in your present job. alive! Circle 126 now! TAPE RECORDERS AND TAPE 109. Seco offers a line of specialized 137. For success in communica- 14. You just gotta get Craig's new and standard test equipment that's tions, broadcasting and electronics get pocket -size, full -color folder illustrat- ideal for the home experimenter and your First Class FCC license and ing what's new in home tape record- pro. Get specs and prices today. Grantham School of Electronics will ers- reel -to -reel, cartridge and cas- show you how. Interesting booklets sette, you name it! It looks like a who's who for the tape industry. 9. Troubleshooting without test gear? are yours for the asking. Get with it -let Accurate Instrument clue you in on some great buys. Why 123. Yours for the asking- Elpa's do without? new "The Tape Recording Omni - HI -FI /AUDIO book." 16 jam -packed pages on facts and tips you should know about be- 145. Alco Electronic Products has 28 104. You can't hear FM stereo unless your FM antenna can pull 'em in. fore you buy a tape recorder. circuit ideas using their remote control avail- relay. Get 100- and -one odd jobs done Learn more and discover what's able from Finco's 6 -pages "Third Di- 31. All the facts about Concord at home without calling an electrician. are Get all the facts today! mensional Sound." Electronics Corp. tape recorders yours for the asking in a free booklet. Portable, battery operated to four - 119. Kenwood puts it right on the SCHOOLS AND EDUCATIONAL track, fully transistorized stereos cov- line. The all -new Kenwood FM- stereo er every recording need. *136. You can become an electrical receivers are described in a colorful 16 -page booklet complete with easy - engineer only if you take the first 34. "All the Best from Sony" is an step. 136 will send to-read- and -compare spec data. Get Circle and ICS your copy today! 8 -page booklet describing Sony- Super- you their free illustrated catalog de- scope products -tape recorders, mi- scribing 17 special programs. ICS crophones, tape and accessories. Get also has practical electrical courses 30. Shure's business is hi -fi car- a copy today before you buy! that'll increase your income. tridges, tone arms, and headphone- amps. Make it your business to know 35. If you are a serious tape audio- *74. Get two free books -"How to Shure! phile, you will be interested in the Get a Commercial FCC License" and all new Viking /Telex line of quality "How to Succeed in Electronics" - tape recorders. from Cleveland Institute of Electron- 17. Mikes, speakers, amps, re- ics. Begin your future today! ceivers -you name it, Electro -Voice makes it and makes it good. Get the TELEVISION straight poop from E -V today. *3. Get all the facts on Progressive 70. Need a new TV set? Then as- Edu -Kits Home Radio Course. Build kit. Heath has 99. Get the inside info on why semble a Heath TV 20 radios and electronic circuits; solid all sizes. B &W and color, portable parts, tools and instructions come Koss /Acoustech's -state ampli- and fixed. Why not build the next with course. fiers are the rage of the experts. Col- watch? orful brochure answers all your ques- TV you tions. 142. Radio-Television Training of 127. National Schools will help you America prepares you for a career - learn all about color TV as you not a job. 16 big kits help you learn 26. The all new, lavishly -illustrated, assemble their 25 -in. color TV kit. as you build. 120 lessons. Get all the full -color brochure, "At Home With Just one of National's many exciting facts today! Stereo" clues you in on H.H. Scott's and rewarding courses. n

SCIENCE AND ELECTRONICS Indicate total number of booklets requested Department 1169 229 Park Avenue South 1 2 3 4 5 6 7 8 9 10 New York, N.Y. 10003 11 12 14 17 23 26 30 31 34 35 Please arrange to have the lit- 42 44 45 46 48 70 74 78 96 99 erature whose numbers I have circled at right sent to me as 100 101 102 103 104 106 107 109 111 114 soon as possible. I am enclosing 25C to cover handling. (No 116 118 119 123 126 127 129 130 135 136 stamps, please.) 137 140 141 142 143 144 145 146 Sorry, only 20 circled items maximum. NAME

ADDRESS

CITY

STATE 7IP

OCTOBER -NOVEMBER, 1969 25 Can you solve these

two basic problems in . electronics?

Lamp1 Lamp 2 Lamp3 Z: 10 volt zener diodes

This one is relatively simple: This one's a little more difficult: When Switch S2 is closed, which lamp What is the output voltage (p-p)? bulbs light up? Note: If you had completed the first lesson in the Note: If you had completed only the first lesson new courses in Solid State Electronics, you could of any of the RCA Institutes Home Study programs, have easily solved this problem. you could have solved this problem. These new courses include the latest findings and techniques in this field. Information you must have if you are to service today's expanding multitude of solid state instruments and devices used in Television, Digital, and Communications Equipment.

If you had completed an entire RCA Institutes Home Study Course in Semiconductor Electronics, Digital Electronics, or Solid State Electronics, you should now be qualified (d-d) spoA 01-1 walgord dn ig6u pe 6ag1-L walgad :Sd3MSNtl for a good paying position in the field you choose. Send for complete information. Take that first essential step now by mailing the attached card.

26 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER RCA Institutes Autotext learning method makes problem -solving easier... gets you started faster towards a good -paying career in electronics

-Yours To Keep Are you just a beginner with an interest In Valuable Equipment electronics? Or, are you already making a living A variety of RCA Institutes engineered kits are in electronics, and want to brush -up or expand included in your program of study. Each kit is yours your knowledge? In either case, RCA has the to keep when you've completed the course. training you need. And Autotext, RCA Institutes' Among the kits you construct and keep is a working own method of Home Training will help you learn signal ,generator, a multimeter, a fully more quickly and with less effort. transistorized breadboard superheterodyne AM receiver, and the all- important oscilloscope. Wide Range of Courses These 4 kits are at no extra cost. Compare this Select from a wide range of courses. Pick the selection with other home study schools. best and check it off on the one that suits you Convenient Payment Plans attached card. Courses are available for beginnerS Institutes offers liberal monthly payment and advanced technicians. RCA plans to suit your budget. Electronics Fundamentals Training Also Available Black & White Television Servicing Classroom technical (Transistorized TV Kit Available) RCA Institutes operates one of the largest No Color Television Servicing (Color TV Kit Available) schools of its kind. Day and evening classes. courses FCC License Preparation previous training is required. Preparatory Automatic Controls are available. Classes start four times a year. Automation Electronics Job Placement Service, Too! Electronics Industrial like Bell Telephone Labs, GE, Nuclear Instrumentation Companies IBM, RCA, Westinghouse, Xerox, and Electronics Drafting Honeywell, radio and TV networks have regularly Computer Programming major employed graduates through RCA Institutes' own Plus these new placement service. up -to- the -minute courses All RCA Institutes courses and programs are Semiconductor Electronics approved for veterans under the new G.I. Bill. Build and keep this Digital Electronics valuable oscilloscope. Send Attached Postage Paid Card Solid State Electronics Today. Check Home Study or Communications Electronics Classroom Training. Prepare for good paying Accredited Member National Home Study Council. positions in fields like these r Television Servicing IF REPLY CARD IS DETACHED, SEND THIS COUPON Telecommunications RCA Institutes Inc. Mobile Communications Home Study Dept. RX -09 CATV 320 West 31 Street Broadcasting New York, N.Y. 10001 Marine Communications In the new program on Solid Please send me FREE illustrated career catalog. State Electronics you will study Instrumentation temperature and Nuclear the effects of Age leakage characteristics of Name Industrial Electronics (please pant) transistors. Automation Address Computer Programming City State Zip Solid State J Electronics Drafting RC,' L

29 OCTOBER- NOVEMBER, 1969 PRECISiON APPROACH by Jack Schmidt

- ' ? OF FIRE -''L ó owly-CASE cc W.T/E OR gIRCN I1NO RED C7:FT IEVa OpVE REO ®MOVE RT LL re< ©RFSURE couT MTD CCORO SURE -'oeE REO6 IVcKIFo cDMLrt. ®O,NEM RErtM ñSnrEyTR/E pryT: liyLñS E T ONE k, R

"Roger, 4175, it is confirmed ... * "Our pulsing sonar shows it to be . we have you in radar contact!" * over 80 feet deep along here."

" . thereby turning off the light * ".. , adjust to 3147.42 kHz, or when-the closet door is closed!" c give the chassis a rap with a hammer!"

30 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER NDUCTOR!

Some copper, some lead, sore water, a spoon- iul of che- iical, and you've made a PHOTOCELL! common- THE PAST few years, solid state electronics have become OR in place. However, back in the Roaring 20s, before the transistor, pioneers most electronics experimented with many unusual dev ces. One of the an inexaensive, iiteresting devices a~ this period was the liquid photocell, si y made ihotovoitaic cell houses in a glass jar containing

by Charles G -een, 1146FFQ

31 OCTOBER-NOVEMBER, 1969 Liquid When a load is connected to the electrodes, a small DC current flows from the photo- Semiconductor cell. The amount of DC current is determined by the internal resistance between lead electrodes and a liquid electrolyte, lead the copper and lead electrodes through the nitrate. electrolyte. A thin coating of copper oxide on the This internal resistance varies with the copper electrode acts as the photosensitive condition of the copper oxide coating on element. You can experiment with the liq- the copper electrode, which is the photo- uid photocell by building this liquid semi- electric sensitive surface. When light strikes conductor described in the article and in the copper oxide, electrons are emitted, and the accompanying drawing and photos. Also the internal resistance of the photocell is included are plans for a variable sensitivity changed. This causes a larger DC current to meter module that can be used to test DC flow out of the photocell into the load. The current output of the liquid photocell. amount of light controls the DC current out- How It Works. When radiant energy, in put; the more light, the more current output

1111/1111111111 11

Liquid photocell pro- COPPER duces output of several LEAD 100 -WATT LAMP milliamperes propor- tional to intensity of light shining on it (the more light, the more LIGHT PHOTOCELL current). Cell can be re- juvenated by renewing cuprous oxide on the LIQUID PHOTOCELL OPERATION copper surface.

the form of visible light, strikes a suitably from the photocell. prepared metallic substance, electrons are Construction. You will need sheet cop- emitted. In the absence of light, the copper per, a strip of lead or lead solder, and a and lead electrodes of this photocell have a glass jar approximately 43/4 -in. high with a small potential difference, as does an elec- 23/4 -in. diameter (we used a "Maxim" in- trochemical battery with no load applied. stant coffee 4 -oz. jar). The size of the jar

,,,,.,,m,,,mm,,,..m,.,,,,,,,,,m,mnimmn..mmm.,,,,,..mm,mmmMM.m.mMelmme

FAHNESTUCK CLIPS ANO 6-32 MACHINE SCREWS ANO NUTS

PLASTIC TOP (COFFEE JAR TOP)

31 IN. PIECE OF LEAD QRWIRE SOLDER MOUNTED IN. IN FRONT OF COPPER STRIP COPPER OXIDE

GLASS JAR APPROX. SHEET COPPER APPROX. 41 IN. HIGH x 21 IN. 3i IN. LONG x 11 IN. WIDE ( "MAXIM" COFFEE WIDE. TOP END HAS A 4 OZ. JAR OR EQUIV. + IN. ANGLE SECTION

REAR OF COPPER IS Details of cell's construction appear in COATED WITH BLACK PLASTIC drawing (right) and photo (above). We TAPE - AFTER SPACED APPROX. ¡ IN. COPPER HAS FORMED APART used plastic cap supplied with Maxim THE OXIDE (SEE TEXT) coffee jar to insulate electrodes. Be sure to cover rear of copper electrode with plastic tape after oxide forms.

32 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER oxide is off, as the inner layer of cu- is not critical, but the jar must be made of black may also start to dissolve. Re- clear glass and should have a plastic lid, or prous oxide copper from the ammonia and you will have to make a wooden or plastic move the it in water to remove the ammonia. lid to fit. The copper sheet may be difficult wash angle.) to obtain. We cut and flattened a length of (Hold it by the the copper strip is soaking, drill the 1/2-in. copper tubing for our model. While the jar and mount a length of Begin construction by cutting a 4 -in. x plastic cap of not cored) or a thin 11/4-in. piece of sheet copper. Bend one end wire solder (preferably lead to a Fahnestock clip fas- to form a right angle 1 -in. wide, and drill strip of pure to the lid as shown in the drawing. a hole to clear a 6 -32 machine screw in the tened electrode to a length of 31/2-in. center, as shown in the drawing. Before the Cut the lead copper strip has been washed, copper strip can be used, a coating of cu- After the prous oxide must be formed on it to serve as the sensitive surface. Hold the sheet by the 1/2-in. angled section with a large pair of pliers and heat the copper strip evenly in the flame of a gas stove or a torch. Hold the strip well inside the flame, so it does not become covered with soot. Heat the copper until it becomes uniformly dark, then remove the strip from the flame and allow it to cool. Do not let the surface touch anything. The black surface of the copper strip is cupric oxide. Just below the cupric oxide is a thin layer of cuprous oxide -actually the photosensitive oxide. After the copper strip cooled, place it in a jar filled with pure has Both meter and shunt potentiometer are household ammonia. Cap the jar and allow fiberboard panel. Supporting the mounted on the copper strip to soak until most of bracket is formed from wire coat hanger. black oxide is off. Cuprous oxide has a red color, but because the layer is so thin it may be difficult to see. Also, the ammonia devel- ops a bluish tint from the dissolved copper oxide; therefore, don't wait until all of the

BILL OF MATERIALS FOR LIQUID SEMICONDUCTOR J1, J2- Fahnestock clips (Lafayette 3277601 or equiv.) R1- 1500 -ohm potentiometer fiberboard 1 -4 x 5 -in. sheet of 1 -Glass jar (see text) 1-11/4 x 31/2-in. sheet of copper (see text) lead 1- 31/2 -in. -long piece of lead solder or strip (see text) (Lafayette 9975052 or 1 -0 -1 mA milliameter equiv.) or 0 -5 mA milliameter (Lafayette 9975053 or equiv.) Misc.- Screws and nuts, black plastic tape, wire coathanger, hookup wire, etc.

Bill of Materials above specifies either 0 -1 or 0 -5 mA milliammeter, since actual value isn't critical. Idea here is to let you use whatever is in text, most readily available. As explained meter panel rests at convenient to calibrate meter. Completed 100 -watt lamp is required angle on supporting bracket. Pair of Fahne- stock clips mounted at top serve as terminals.

33 OCTOBER- NOVEMBER, 1969 Liquid Semiconductor

mount it approximately 3/ -in. away from LEAD the solder as shown in the drawing. Do not touch the photosensitive surface with your fingers. LIQUID PHOTOCELL Cover the rear of the copper strip with black plastic tape so that light will strike only the surface facing the lead electrode METER and the light source. ASSY. WITH RI SENSITIVITY CONTROL Fill the jar with water to just below the Potentiometer R1 is shunt to adjust range of plastic top, making certain that the water 0 -1 mA meter. It is best viewed as a sensitivity level is below the end of the machine screws control allowing a wide range of readings. holding the electrodes to the jar cover. Dis- solve one teaspoon of lead nitrate in the The photocell has to he aged with the water. Note: all lead compounds are poi- meter connected, until the dark current (DC sonous, therefore thoroughly wash your current output with no light) is from 0.3 to hands and all items that were in contact 0.5 mA. This aging may take anywhere with the lead nitrate. Lead nitrate can be from several minutes to an hour, depending obtained from a chemical supply or student upon the quality of the cuprous oxide layer science store. After the lead nitrate is dis- on the copper electrode. solved, screw on the plastic cap and elec- Testing the Photocell. Place a 100 -watt trode assembly. The water should be clear. lamp near the photocell on the side near the If, because of chemical treatment of your lead electrode. Turn the lamp on and ob- local water, it does not remain clear after serve that the photocell DC current output adding the lead nitrate, you may have to increases. Adjust the meter module sensi- use distilled water to mix with the lead ni- tivity control as necessary for an indication. trate electrolyte. The amount of current increase will depend The Photocell Meter. The liquid photo- on the quality of the cuprous oxide layer cell has a low impedance output; therefore, formed on the copper electrode. Our unit it requires a low resistance meter for accu- had a 2 mA increase. rate readings. A 5 -mA milliammeter should Experiment with various lamps of differ- be used to indicate the change in the DC ent wattages, as well as with fluorescent current output. A VOM with an equivalent lamps. Also test the photocell in sunlight. 5 -mA range usually has a higher internal Make a chart of the photocell DC output resistance and will not indicate as well as current readings obtained with the lamp at the individual meter. different distances from the cell. Our meter module unit contains a 1 -mA The liquid photocell has a definite life meter movement with a variable sensitivity span. As it is used, you will notice that the control connected in parallel with the meter copper electrode becomes darker and the (see the drawing). We built our module on DC current output from the light source di- a 4 x 5 -in. piece of fiberboard. Coathanger minishes gradually. This occurs because wire is bent into a support bracket and is lead is gradually being deposited on the cop- bolted to the bottom of the fiberboard as per strip through internal electrochemical shown in the photo. activity. Connect a 5 -mA milliammeter or the When the DC current output becomes too meter module, to the photocell terminals as low, remove the copper electrode from the shown in the drawing. The copper electrode photocell, clean the surface with sandpaper, is connected to the meter plus terminal and and then reheat the copper strip to form a the lead one is connected to the meter nega- new oxide coating, as previously described tive terminal. There may be a high current in the construction of the photocell. Remove output from the photocell momentarily. If the oxide from the copper with ammonia, so, short out the photocell terminals (or wash and replace the copper electrode in turn the meter module sensitivity control to the photocell. In this way the photocell will minimum resistance) until this output cur- have an indefinite life just by renewing the rent drops. coating on the copper strip.

34 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER COVER STORY

Now! Control exposure time, development time, any darkroom function with our

UNIVERSAL DARKROOM TIMER by Ron Michceils what's the most im- In addition to the purest of chemicals and water, involving portant factor influencing photographic processes- whether of course! films or prints and most decidedly in the case of color? Timing, want to pro- Accurate, repeatable timing ;s a must in the darkroom if you duce consistently good work. and repeat- Our Universal Darkroom Timer provides both accuracy control exposure time ability over a wide range. This solid -state timer can to calling as well as development time at the flick of a switch. In addition

-35 OCTOBER -NOVEMBER, 1969 Universal TIMING TABLE A -For enlarger timing of 0 -7 seconds and Darkroom process timing of 0 -7 minutes R1- 50,000 -ohm potentiometer R3- 10- megohm potentiometer Timer C1- 200 -DF, 350 -V electrolytic capacitor B -For enlarger timing of 0.10 seconds it a Universal Timer, we should also refer and process timing of 0 -10 minutes to it as a Custom Designed Timer. Reason R1- 50,000 -ohm potentiometer is that with the exchange of just a few criti- R3- 10- megohm potentiometer C1- 300 -uF, 350 -V cal components the timing cycle ranges can electrolytic capacitor C -For enlarger timing of be tailored to fit your particular darkroom 0 -15 seconds needs. and process timing of 0.15 minutes R1- 100,000 -ohm potentiometer For example, we prefer never to expose R3- 10- megohm potentiometer print paper for more than seven seconds C1-400 -uF, 350 -V electrolytic capacitor when using the enlarger- that's the maximum exposure time in the process we use. Also, we never keep negatives in their de- on (allows current flow to pass through), veloping solutions for more than seven AC current can flow through the bridge minutes. Since these two ranges represent rectifier (Q2) and the load, or whatever is the maximum timing cycles we use, we se- plugged into the output sockets. When the lected the components that produce these SCR is turned off the bridge acts like an ranges for our timer. The Timing Table in- open switch and no current flows through cluded with this article gives the proper the load. The balance of the circuit is an values of the key components for several unique biasing arrangement that adapts the other timing ranges. switching circuit to function as two different How It Works. A full -wave silicon con- timers. trolled rectifier (SCR) switching circuit is Key point to remember in the following the heart of our timer. When the SCR turns circuit description is that the SCR remains

_1111,1111111,1WU.1,,,,,111111111,1,1111,111111,11111111,1,,,,111111111111111,,,1111111111111,,,1111:,111,,,,111,11,11,,1 ,,,,,,,, , ,,,,, ,,,,,,,,,,,,,,,,,,,,,,1,,,,,,,,.,,w,.,,iala1w11.,,,,,,

01 ENLARGER

SS1B

D2 R6 1800 ST-2 T ,SSTART 02 T1 02

b PROCESS ENLARGER- PROCESS blk °,o

° ° C2 S1A á e 100NF t a R3 a gr 10 MEG R1 '(SEE TEXT) 01 R5 TIME TIME a 10681 NC 680K bIk ! READY FOCUS R4 r grn R2 - - 546 1 MEG 4700 S3 Rg TIME S TIME D1 6800 S4A

POWER R8 READY HEP 311 Cl 68K R10 R7 820 (SEE 820 TEXT)

4-4117 VAC

g111,111111 1111 11111111111111111111111111 11111 111 11 11 11 111111 1111111111 11111111 11 11 11041111111 36 is charged to approxi- on (and the bridge conducts) whenever a timing capacitor Cl Instantly this voltage current of more than 200 microamps (1/5 mately 200 VDC. amount of current into of a milliamp) is fed into the gate terminal. sends a substantial SCR, turning it on The Enlarger Timer. The desired opera- the gate terminal of the rectifier bridge current tion is that the enlarger lamp will turn on and thus permitting Switch SI is a at the touch of a button, remain on for a to flow through the load. is used to present time period, then will turn off auto- double pole unit; one section outlets matically. The desired time period is se- select one of the two convenience switching cir- lected by an adjustable control (R1). When to be connected to the timer function switch SI is placed in the ENLARGER cuit. When Si is placed in the ENLARGER position, the timing circuitry for this func- position, outlet "01 ", labeled ENLARGER, IS is the outlet the Enlarger's tion is actuated. This is a very straightfor- connected. This ward operation. power cord is plugged into. gate When pushbutton switch S2 is depressed, The SCR remains on as long as the

Rear view of timer assembly showing locations of two outlets where power cords for audible indicator for both process timer and enlarger are plugged in. Right -hand outlet is connected to short duration timing circuit for enlarging; left -hand outlet is connected to long duration timing circuit for processing. Bell or buzzer is powered through latter outlet.

PARTS LIST FOR UNIVERSAL DARKROOM TIMER resistor C1- Electrolytic capacitor, 350 volt rating, R4- 1- megohm, r/2 -watt 1/2 -watt resistor 200 uF (for 0 -7 sec timing) (Cornell Dubilier R5- 680,000 -ohm, 1/2 resistor BR200 -350 or equiv.); 300 uF (for 0 -10 sec. R6- 1,800 -ohm, -watt resistor timing) (Cornell Dubilier BR300 -350 or R7- 820 -ohm, 1/2-watt 1/2-watt resistor equiv.); 400 uF (for 0 -15 sec. timing) (Cor- R8- 68,000 -ohm, resistor nell Dubilier BR400 -350 or equiv.) R9 -6,800 -ohm, I/2 -watt R 820 -ohm, 1/2 -watt resistor C2 -100 uF, 250 volt electrolytic capacitor 10- toggle switch (Allied 56F3867 (Cornell Dubilier BR100 -250 or equiv.) Si, S4 -Dpdt D1- Silicon, bilateral trigger diode (Motorola or equiv.) open pushbutton switch HEP 311) S2 -Spst, normally or equiv.) D2 trigger diode (GE ST -2) (Allied 56F4947 -Diac or equiv.) 01, 02-Panel mounting AC socket (Allied 53, S5 -Spst toggle switch (56F3869 117 volt pri.; 125 47F0830 or equiv.) T1 -Power transformer, and 6.3 volt, 1 amp. Q1- Silicon controlled rectifier (SCR) (GE volt, 0.15 mA sec. used) (Allied 54F4163 or equiv.) 106B1) sec. (not 3 -front cabinet (Allied Q2- Bridge rectifier (International Rectifier 1 -8 x 5 x -in. sloping or equiv.) I ODB6A) 42F8686 (Allied 47F2917 or R1- Potentiometer, 50,000 ohm for 0 -7 sec. 1- Terminal tie strip and 0 -10 sec. timing (Allied 46E5314 or equiv.) equiv.); 100,000 ohm for 0 -15 sec. timing (Allied 46E5317 or equiv.) -ohm, 1/2 -watt resistor R2 -4700 wire, solder, cement, fiber- R3- 10- megohm potentiometer IIRC -CTS D106 Misc.- Hardware, with shaft 18 or equiv.) glass tape, labels, etc. schematic Schematic detailing Universal Darkroom Timer. Note that text and is marked refer to a position of S4 as "Ready" whereas in the photo this position you want. "Reset." These designations are interchangeable, so mark your timer as

37 OCTOBER -NOVEMBER, 1969 it into wall outlet. When S3 is placed in Universal FOCUS position, the enlarger lamp is turned on and remains on until S3 is placed in the Darkroom off position, where it must remain whenever using the timer to time an operation. The Process Timer. For this function the Timer timing cycle is of much longer duration (several minutes), and the timer should current flow continues. However, the com- sound a signal at the end of the present bined current drain of the SCR and the ad- timing interval. When S1 is placed in the justable shunt resistance, consisting of R1 PROCESS position, a biasing circuit is acti- in series with R2, rapidly 'discharges timing vated that is virtually the opposite of the capacitor Cl. The exact time of discharge circuit for the ENLARGER timing just de- is dependent on the setting of R1. Within scribed. a few seconds C1's voltage falls below the The PROCESS timing operation is con- breakdown voltage of trigger diode D1 trolled by toggle switch S4. With S4 in the

Timer assembly with cover of 02 cabinet removed to show (BRIDGE RECTIFIER) S1 mounting of components on D1 TB1

"U" shaped section of 01 S3 cabinet. This becomes front (SIR) 01 panel, bottom, and rear panel of timer cabinet assembly. 02 All controls except for power 02 switch 55 are mounted on front panel (power switch was C2 placed on rear panel to

simplify wiring). Even if timer C1 should inadvertently be left turned on for long periods of S5 time no harm will result. Nor will your power bill zoom, as T1 timer requires little power.

T1 S5 01 Q2 Cl C2 View shows front panel and interior layout of timer assembly. Notice how Cl and C2 are taped together and cemented in position on rear panel. With exception of variable resistors, all semi- conductors and resistors are placed on an insulated tie strip, to which tie strip terminals have been staked. Strip is mounted adjacent to power transformer on bottom of cabinet and raised by spacers to prevent RI shorting R3 S4 S1 S3 S2 out circuitry.

(about 30 V) and the diode blocks any READY position, capacitor Cl is kept fully further flow of current into the gate of the discharged and the SCR is kept turned off. SCR. Therefore, no current can flow through the Pushing S2 a second time recharges Cl load (in this case some type of 117 -volt and recycles the timing circuit. Toggle operated signal device -a bell, horn, or buz- switch S3 has been added as a bypass switch zer). When S4 is switched to its TIME posi- to enable focusing the enlarger without hav- tion, capacitor Cl is connected to the 200 - ing to disconnect it from the timer and plug volt DC supply through a high value re-

38 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER power trans- chain composed of potentiometer the cabinet's base next to the sistance except for power R3 in series with R4. former. All other controls on the front panel. Because of its high capacity, and this re- switch S5 are mounted outlets and the power sistance chain, Cl charges very slowly, and, The two convenience the rear of the cabi- after several minutes (the exact time is de- switch are mounted on pendent on the setting of R3), the voltage net. capacitors, Cl and across capacitor Cl reaches the breakdown The two electrolytic together with fiberglass voltage of diode D1. Instantly the capacitor C2, are first taped cemented to the in- begins to discharge through the SCR gate, binding tape and then of the cabinet. Be- turning the SCR on and allowing current side surface of the rear tie strip to the cabinet to flow through the load, which in this oper- fore fastening the all of the components men- ation is the signaling device. base, mount With Si in the PROCESS position, outlet tioned above to it. draws so little current in stand- "02" is activated through the timer. How- The timer harm would result from ever, after about 5 seconds, Cl's voltage by condition that no on when the unit was falls below the critical diode breakdown leaving the power

Finished product is very professional looking timing device that is of inestimable value in any darkroom, be it for professional or amateur photographers. It combines facilities to time development of film and /or paper as well as exposure timing for the enlarger. Incorporating silicon controlled rectifier and sophisticated timing approach, unit provides two different timing ranges economically by sharing common components.

Therefore, to facilitate the potential, current flow stops, the SCR is not being used. wiring, the power switch turned ofi, and the signaling device stops parts layout and the the rear panel. sounding. The capacitor then again begins was mounted on Timer. Once the proper building up to the breakdown potential, at Calibrating the been chosen, and the which point the signal device would again timing ranges have in the Timing Table activated. However, the person using the components specified be the circuit, calibration timer would normally interrupt the cycle as have been wired in on the panel adjacent soon as the signal is first sounded. Used in points can be marked R1 and R3. The exact this manner our circuit behaves in much the to the knobs for are determined by same way as an electrical or mechanically locations of the marks checking the timing of on status with a stop- driven clock. desired the Timer. We housed our watch at each of the timing periods Building darkroom process. timer in an aluminum cabinet having a cowl to meet your particular of the components in the front. Our reason for using this type of Because many to both timing oper- is the overhang, or cowl avoids circuitry are common cabinet that between the operation of the controls in the ations there is some interaction accidental For this reason it darkroom. The unit has been well designed two adjustable controls. that S4 be kept in the READY and packs a lot of circuitry into a small is important using the unit as an en- space. Even so, there is ample room to position whenever easily wire the components if you follow larger timer. an advantage layout as shown in the photos. Our Universal Timer has our change resistors, the bridge rectifier, over commercial units. Should you All of the which the SCR, and diode Dl are mounted on a your photo processing procedures, this can be phenolic board containing staked terminals, may require a change in timing, a few parts. which, in turn, is mounted in the center of easily done by exchanging 39 OCTOBER -NOVEMBER, 1969 Did you 0 a1:..

. . . clouds of nitrogen dioxide were recently studied remotely by a team of Canadian scientists? Working under an HEW contract and using a unique, telescopic, gas- analyzing spectrometer, Toronto's Barringer Research Inc. was able to perform quantitative chemical analyses of polluted air over the Los Angeles basin without making physical contact with the material under study.

. . . new ICs help put market trans- actions on brokers' desks? Developed by Trans -Lux Corporation, the new Vidi- Quote records current stock- exchange information in binary code, then converts it to alpha- numeric characters which are displayed on a compact TV monitor. Its ICs are by Texas Instruments.

. . . FM radios alert emergency personnel in an unusual use of a CATV system? Cablevision of Virginia, the firm responsible for the community -minded hookup, speeds emergency squad members to disaster scenes by sending distress calls over its CATV system. A Jerrold- operated company, Cablevision devised the hookup to supplement the klaxon atop the courthouse in Clifton Forge, Va. Results are swifter and surer rescues.

40 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER If you don't live so far away from a police New or fire transmitter that a strong wind is adventures needed to blow the signal out to you, you in can throw together a six -buck vhf converter fuzz snooping for listening to these calls in less time than for it takes a soldering iron to heat up. By the time the iron is hot you'll have all the parts six mounted and ready for final soldering. bucks! ! The six -buck converter uses very few parts: a 9 -volt battery, a small 5 -k pot with a switch and a Cordover CM -H FM Con- verter Module. The parts can be mounted by about any type of housing -they can Allen in just James

W,p,313=: rftcz', y:'i

41 OCTOL'ER- NOVEMBER, 1969 module's internal oscillator to 52 MHz, the PC1130g 52 MHz oscillator signal will beat with the 152 MHz received signal and will produce ggET2 new signals equal to the sum and difference of the oscillator and received signals. (152 even be wired together without a housing. If MHz + 52MHz = 204 MHz and, 152 MHz you want to go the deluxe route, you can - 52 MHz = 100 MHz). These new signals build the unit in a small utility box for ap- appear at the module's output along proximately with one more dollar, and include a the original 152 MHz and 52 MHz signals battery connector instead of directly -wired/ for a total of at least four frequencies: 204 soldered battery connections. MHz, 152 MHz, 100 MHz and 52 MHz. Works With FM. Unlike the more com- Since the FM radio is tuned to 100 MHz, monly used converters that are operated in only the 100 MHz signal will he received by conjunction with an AM radio as the basic the FM radio and the audio output of the

ANTENNA CABINET FRONT PANEL

Practically any mounting arrangement will work for Police Converter, but it's best to keep leads from R1 to module as short as possible. Module (at right) is roughly size of ice cube.

receiver, and since vhf police and fire signals Schematic of are FM, if the CM -H converter module is Penny Pinch- used with an FM radio you will get better TUNING. er's Police sensitivity. o Converter is Even though it's possible to receive FM simplicity in signals on an AM radio by using slope de- R1 itself. What tection and by tuning the AM set to the 5K unit lacks in sensitivity it sideband of the received signal, since police makes up in and fire FM signals are narrow band FM (actually ease of split channel), by the time these assembly and signals have passed through the slope de- low cost. tector there would not be much modulation left. PARTS LIST FOR PENNY PINCHER'S How It Works. The converter module POLICE CONVERTER works on the heterodyne principle, similar B1 -9 -V battery (Lafayette 9976021 or equiv.) to that used in a standard BC radio. Within 1 -CM -H Cordover vhf police and fire conver- the module is an adjustable oscillator whose ter module (Lafayette 1975528 or equiv.) frequency is approximately 88 -108 MHz re- R1 -5000 -ohm potentiometer with spst switch moved from the frequency of the desired (51) (Lafayette 3277363 or equiv.) signal. To illustrate, let's assume the desired Misc.- Plastic box (Lafayette 9978078 or frequency is 152 MHz, and we want the 152 equiv.), hardware, hook -up wire, battery MHz signal to be received when the FM terminal (Lafayette 99T6287), metal strop radio is tuned to 100 MHz. If we adjust the to hold battery, solder, etc.

42 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER will be the modulation of the 152 module's connecting leads and the external radio kept signal. connections. Make certain all leads are MHz to To provide for reception of various police away from the metal panel; use sleeving touch the and fire vhf channels and to ensure that make certain the splices can't the signal can be heterodyned to a quiet spot panel. of the of the FM band, the internal oscillator of Drill a 1/2-in. hole through the top lead from the the module is adjustable over a very wide plastic case for the connecting of range, covering reception of the total 150- module to the FM radio (24 -in. length the wire 164 MHz band, which can be positioned on stranded insulated wire). Pass just about any part of the FM band. through this hole and then secure the front Certainly for $6 one doesn't expect to panel with the screws supplied. Finally, at- -con- obtain the most sensitive of converters. The tach a small alligator clip to the radio unit we assembled was effective up to five necting wire. miles away from base stations of police and Aligning Converter. Extend the whip

and adjust Completed Converter mounted in plastic box sports symmetrically placed tuning FM set. controls. Converter's antenna lead is ideally clipped to whip antenna on associated

con- fire transmitters, and reception from mobile antenna of the FM radio and clip the units was limited to one or two miles, de- verter wire to any part of the FM antenna. pending on the terrain. Tune the radio to a dead spot on the band - Turn By feeding output of the converter to an preferably between 90 and 100 MHz. FM radio, the signal is detected by an FM on the converter by rotating RI's knob, and detector and maximum modulation is ex- then very slowly, advance R1 until the back- tracted from the signal. The converter ground noise heard in the radio reaches a too far module uses a single 24-in. wire lead both usable volume. If R1 is advanced and as the receiving antenna and the radio coup- the radio will block up. It will go quiet ling. The lead is clipped or connected to you may hear several different FM com- The the antenna of the FM radio. The antenna mercial radio stations as RI is adjusted. noise serves both as the antenna for the module correct R1 adjustment is maximum and the converter /radio coupling. just before "blocking." As a double check, Building the Converter. Our converter when Rl is correctly adjusted you will hear is built on the front panel of a 4 x 21/2 x 15/s- clicks as you touch the FM antenna. FM in. utility case. The converter module is If possible, borrow a friend's vhf mounted on the front panel by pushing the police and fire receiver and tune in the local module's mounting clip through a 27/64-in. police or fire frequencies. When you hear in this receiver, adjust the or a 13/32 -in. hole. Adjustment control a transmission slug of the converter module until R 1 /S1 should be mounted as close as pos- tuning bor- sible to the module. Connections should be you hear the same station. If you can't made directly to the module's leads; do not row a receiver, you'll just have to be patient attempt to use terminal strips between the (Continued on page 109)

43 OCTOBER -NOVEMBER, 1969 NOZINOH NN3HINON

DIMt)rv1oel 14111011) ' ,N3dd10 311111. NONNI The 0.4* Skies Above Us

SOUTHERN HORIZON by Dr. Roy K. Marshall The Night Sky in October ** A pair of 7x50 binoculars or a mo- tograph can be exposed as long as we wish, nocular of that size and power can be very to build up the strength of the image and useful in prowling along the Milky Way. reveal the structural details. (The 7 indicates the magnifying power, in Another object that is disappointing vis- diameters; the 50 tells the diameter of the ually but shows intricate filamentary struc- front lens, in millimeters.) About Novem- ture in photographs has recently come into ber 1, the most distant object in the sky that astronomical news in connection with the can be seen without optical aid might be strange, periodically pulsing sources of radio picked up with such a glass, as a smudgy, signals called "pulsars." The gaseous neb- slightly elongated haze, then looked for with- ula itself has been known since 1731, when out the glass, just so you can say that you the astronomer Bevis ran across it; in a saw light that is 2,200,000 years old! large telescope it is a hazy, elongated faint The great galaxy in Andromeda stands patch of light. It has been called the "Crab almost exactly overhead at 10 p.m. on the Nebula," from a fancied resemblance to date suggested above. It consists of about that animal. 150 billion stars arranged in a great spiral The gas cloud, first seen by Bevis in 1731, form that is so distant that light from it ar- lies in Taurus, in our eastern sky on Nov. 1, riving here now left there more than two closely south of the "A" in Taurus on our million years ago. And light, remember, map for Nov. 1 at 10 p.m. travels at a speed of 186,300 miles per * A close friend of mine among astron- second. omers, Dr. John Charles Duncan, examined Our sun is one of the stars in a similar many photographs of the Crab Nebula, taken galaxy, our own, whose flattened spiral shape over decades at the Mount Wilson Observa- is responsible for the appearance of the tory, and found that before 1926, the Crab Milky Way. Nebula had been expanding at such a rate * The galaxies are interestingly detailed that, about 900 years earlier, this cloud of objects as photographed through large tele- gas had been all at one point. scopes, but disappointing as seen with the With the cooperation of a scholar in the eye through the same instruments, because University of California, he discovered that, ,the eye takes only snapshots, while the pho- in the year 1054, Chinese and Korean as-

44 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER NOZIaOH Na3HlaoN This time of year sees the summer stars slipping our s.« NorvN sight in the west and those of the winter coming once .1i3ddI0 OIS.% more into view in the east. The summer Milky Way arches from the southwest, through Sagittarius, N3dd10 3-111I1. Aquila and Cygnus, then thins into the winter NONIN \tlSNrl Milky Way and passes into Cepheus, Cassi- IYrli c>.rorl acrio opeia, Perseus, and finally through Auriga in the northeast. The "summer triangle" of Altair in Aquila, the Eagle, Vega in Lyra, the Lyre, and Deneb in the tail of Cyg- nus, the Swan, is still displayed in the west, while the Pleiades glitter above ruddy Aldebaran in the east. The z golden planet Jupiter which glorifies o our sky most of the summer is now N lost in the sun's glare, but the other no á the ringed z x giant of the sun's family, Saturn, is now closest to us (673,000,- 000 miles) and is about midway be- O á tween the two triangles of Cetus and N Nr Aries. Red Mars is low in the south- z W west, in Sagittarius. The almost first quarter moon passes south of Mars on October 17 and again on November 15, while the full moon passes north of Saturn on October 25 and again on No- The maps show the vember 21. Y *' principal' stars and planets which are above the horizon at latitude 34° North at about 9 p.m. standard time at the middle of the month. These mapa are practical star location guides anywhere in the United States throughout the month showing the sky at 10 p.m. on the first and at 8 p.m. on the last of the month. To look at the night sky in October and November, select the proper map and SOUTHERN HORIZON hold it vertically. Then turn the map so that the point of the compass toward which you are facing shows at in November he bottom of the map. Our special thanks go to The Night Sky the Griffith Observatory in Los Angeles, California. tronomers had noted a very bright star in columnist the very spot where the Crab Nebula stands Our new today -a "guest star," which today we call Dr. Roy K. Marshall a nova, or new star, which we know today You wouldn't think the is not really a new star, but one which newly man looking so directly at calls our attention to it. you has spent most of his

A nova is a star which generates energy life gazing at stars . . . so strongly that the overlying layers of the but that's his story. From hold it in, so the star literally ex- a doctorate in astrophys- star can't ics at the University of plodes. For a few days or weeks or even Michigan through stints months, the star may be the brightest object at various planetariums (planetaria ?), Dr. Roy K. in sky, until it subsides to the obscurity Marshall has perhaps not as many qualifications as the has been We have records in there are stars, but enough. Dr. Marshall from which it erupted. associated with the Adler Planetarium, Chicago; both early and later times of many such ex- the Yerkes Observatory, University of Chicago; the ploding stars. Harvard Observatory; the Fels Planetarium, Phila- What we see when we observe the Crab delphia; Morehead Planetarium, Chapel Hill, N.C.; College Planetarium, Odessa, Texas and is is the gaseous debris of Odessa Nebula in Taurus currently Director of the Gibbes Planetarium, Co- the colossal explosion when a star literally lumbia Museum of Science, Columbia, S.C. Dr. Mar- "blew its top." The gigantic explosion oc- shall is the author of "The Nature of Things," curred about 3050 years B.C., .because mod- "Sun, Moon and Planets," "Star Maps for Begin - object's distance hers" and "Sundials." A man for all media, Roy ern measures show that the Marshall has been education director for the Phila- is 4100 light -years. Now, after a lapse of delphia Inquirer radio and TV stations, science almost 5000 years, the Crab Nebula may editor of the Philadelphia Evening Bulletin, colum- now be telling us something of a new state of nist for SKY AND TELESCOPE magazine, and astronomy columnist for SCIENCE AND ELECTRON- matter. ICS. He is the recipient of an honorary degree from * The great radio telescopes have been tell- the Philadelphia College of Pharmacy and Science ing us that something in or near the Crab "for propagating the knowledge of science via planetarium work, radio and Nebula is sending us radio "beeps" at inter- writings, lecturing, television." Let him welcome you aboard on a vals of one -thirtieth of a second. fascinating trip to the heavens! (Continued on page 110)

45 OCTOBER- NOVEMBER, 1969 by James Robert Squires

One of San Onofre's five watch engineers, Pat Riley is empowered with making go /no- go decisions in event of trouble. His job: to make sure that everything remains AOK. SAN ONOFRE'S

Set beside the Pacific Ocean in a man- 450 megawatts of electrical power, 80% made cavity 90 ft. below the cliffs, the San of which is used by the Southern California Onofre nuclear -powered generating station Edison Company and 20% by the San Diego is located roughly 60 miles south of Los Gas and Electric Company, co- owners of Angeles. In operation since January of last the project. year, the station is capable of generating The generating station, which is of the

Twin flash evaporators (left), powered by steam from secondary system, convert sea water into distilled water at rate of 120 gallons per minute. Water is stored in huge tanks for later use; any excess is pumped to reservoir high on cliffs for supplying domestic water needs.

46 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER Overall view of San Onofre. Large sphere at right houses nuclear reactor and its associated steam generators; sphere is vent- ed to relieve pressure in event of mishap. FARULOUS 40 pressurized water type similar to that used member that whenever the pressure on a by nuclear submarines and surface vessels quantity of water is raised above 14.7 typified by the aircraft carrier Enterprise, pounds per square inch (psi), the water has its nuclear reactor located at the bottom will no longer boil at 212 F. Because of the of the big sphere (see our photos). 2000 psi pressure within the reactor's pri- To understand how the station works., re- mary system, water doesn't even boil at the

Steam generators and turbine generator (left) form secondary portion of generating se -up. Though heated by nuclear energy, pressurized water serves only as means of conducting energy between reactor and steam generators. Right, sea intake and outflow pump pit.

47 OCTOBER- NOVEMBER, 1969 SAN ONOFUE FABULOUS 1150

system operating temperature of 575 F -hence the term, pressurized water reactor. In operation, distilled water in the primary system circulates around the nuclear reactor and in doing so ab- sorbs tremendous energies in the form of heat. This pressurized water is then forced to one of three steam generators located with the reactor inside the sphere. Steam produced by these generators is used to drive the plant's turbine -generator, thus producing electrical energy in the same manner as conventional, fossil- fueled stations.

Above, output transformer at San Onofre; below, master control room. Indicator panels continuously flash status of instruments and equipment to engineer in charge; levers control position of rods in core.

Structure immediately in front of sphere is waste collection building. Here, radioactive substances which cannot be otherwise dis- posed of are baled and pressed into cement containers.

48 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER by Don Jensen

Their Time Is Your Time

A multi -million -dollar effort by many nations of the world converts your shortwave receiver into an electronic Timex!

O Regularly as clockwork, the shortwave time stations split the hours into tiny fragments with their incessant electronic pulses. No music, no personalities, no entertainment, not even a newscast to break the monotony. Their programming is a bomb -a time bomb! On the whole, their ticks, tones, and tech data are of interest mostly to scientific sorts who rely on their specialized services. Still, these "clock radios" offer some interesting DX to shortwave listeners. Mention standard time stations, and most SWLs figure you're talking about the 46- year -old WWV, the National Bu- reau of Standards' operation at Ft. Collins, Colorado. For, truth to tell, WWV has been ticking away since 1923 (originally from Greenbelt, Maryland) on 2.5, 5, 10, 15, 20, and 25 MHz. And the more hip also know its Hawaiian counterpart, WWVH, at Puunene on Maui Island, which joined in on 5, 10, and 15 MHz in 1948. Still others are familiar with Cana- da's CHU, widely heard on 3.330, 7.335, and 14.670 MHz. (turn page)

OCTOBER- NOVEMBER, 1969 49 ing can be heard right through the U.S. time Their Time stations. Some identify only in International Morse Is Your Time Code, causing problems for SWLs who can't read CW. Way to get around this is to tape But there are scores of other shortwave the signals, then play them back at half - time stations operating around the globe. speed to decipher the individual di -dah com- They are run by astronomical observatories, binations. private and government labs, and military Three On Five. For openers, stake out 5 commands. MHz during the early evening hours, when Little -Known DX. There are several rea- WWV will no doubt be pounding in. How- sons why many SWLs don't realize the DX ever, during the voice announcement just potential of these services. Some share the before each quarter hour, you may hear a standard frequencies with WWV and CW signal in the background, tapping out WWVH, which usually dominate the chan- the call ZUO three times. This station, one nels. Others have mini- skeds, transmitting of the most frequently heard overseas stan- just a few minutes each week. Then, too, dard time services, belongs to South Africa's some use off-beat wavelengths, which makes Republic Observatory in Johannesburg. Its them tough to tune unless you know when transmitter at Olifantsfontein sometimes and where to listen. puts in a surprisingly good signal for just But when conditions are right, the foreign 4 kW. time -tickers can be logged during the A few hours later, between 0645 and WWV /WWVH silent periods -quarter to 0700 GMT, the same 5 -MHz frequency has and quarter past the hour, respectively -or been offering the electronic time signals of during brief pauses in their voice announce- IBF, the Instituto Elettrotecnico Nazionale ments. Sometimes, unexpectedly, alien tick- station at Turin, Italy. At times it manages

Putting together a OSL collection can be interesting when cards are grouped by topics -stamp collectors do this. A topical collection of time stations on six con- tinents and Oceania set up in a nice display. Fqr once it will be possible td show your friends the interesting world of shortwave listening. The chart at the top of the facing page tells you what will be needed in effort to get a complete set. Some of the nicer QSLs are shown on these pages - JJY- Japan, IBF- Italy, CHU- Canada, VNG- Australia. Get yours today!

ISTRUTO ELETTROTECNICO NAZIONALE " GALILEO FERRARIS" - TORINO

STAZIONE PER SEGNASI Dl TEMPO E FREOUENZA EtEOUENa eTATION CAMPIONE AND IB F DOMINION OBSERVATORY

SI conferma, ringraziando, il OTTAWA CANADA rapporto di ricezione CHU Th,s is to confirm, with thanks, your reception report THANK YOU FOR YOUR IBF REPORT OF THE DOMINION del Tecenher 21 1oí9 OBSERVATORY'S VOICE On TIME SIGNAL ON: alle1_tempo universals. at universel time. 3330 kc. 7335 kc.t LA OIREEIONE DIRECTION 14670 kc.

50 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER STANDARD TIME STATIONS AROUND THE WORLD Country Station Address Frequency When to Tune (MHz) (GMT)

ARGENTINA LOL Observatorio Naval, Buenos Aires, Avenida 5.000 0000-0100 Costanera Sur 2099 AUSTRALIA VNG Australian Post Office, Postmaster General's 7.515 1200-1300 Dept., 57 Bourke St., Melbourne 3000 BRAZIL PPE Observatorio Nacional, Rua Gen. Bruce 586, 8.721 0025 -0030 Rio de Janeiro, GB ZC -08 CANAL ZONE NBA U.S. Naval Observatory, Balboa 5.870 0155 -0200 CEYLON 4PB Colombo Radio, Colombo 8.742 1325 -1330 CHILE CCV Instituto Hidrografico, Casilla 324, Valparaiso 8.205 0055 -0100 CHINA XSG Zikawei Observatory, Shanghai 8.333 0855-0905 CZECHOSLOVAKIA OMA Standard Frequency Station, Budecska 6, 3.170 Evenings Praha 2, Vinohrady ENGLAND MSF National Physical Lab, Teddington, Middlesex 5.000 Evenings GERMANY, EAST DIZ German Geodetic Institute, DDR15, Potsdam 4.525 Evenings GUAM NPN U.S. Naval Observatory 5.448.5 1155 -1200 ITALY IBF Instituto Elettrotecnico Nazionale, Corso 5.000 0645 -0700 Massimo d'Azeglio 42, Torino JAPAN J1Y Radio Research Laboratories, Koganei, Tokyo 15.000 2200 -2300 PERU OBC Comunicaciones Navales Radio, Callao 12.307 0055 -0100 SOUTH AFRICA ZUO Republic Observatory, Johannesburg 5.000 0200-0400

,,,:,,,,,,,,1,1,,,,11,,,11 ii iiii,,1 ,11, , 1111,1,1111,1,1111111,,,IIiI,iii, ii,,,11111,,,,1,,,,,1 , 11,,,,,,,,111,,,1,11,1,,,,,,,,,,,, ,1,11111,1 111111,1.1 ,1,1,,,,,,1,,,,.,,,,,,,.,,,,,,,,,,,,,,.'',,.,.,,.,,,,,,1 ,1 ,,,,iIi,,,,,,,,,,,,,,,,,,i,,,,,,1,,,,,1,,,,,,,,,111 .,,11

to bull its way through the WWV transmis- Off-Beat Frequencies. If you don't want sions, identifying both by CW and voice - to fight the QRM on the standard frequen- in Italian, naturally. cies, switch to the time stations that use the Also noted on 5 MHz from time to time far -out frequencies. For example, there's is LOL, the Argentine Naval Observatory the German Geodetic Institute's DIZ in the station at Buenos Aires. It's identified by East Berlin suburb of Potsdam. (Its 5 -kW its thrice- repeated Morse call letters. Un- transmitter, on 4.525 MHz, is actually lo- fortunately, while the station's staff claims cated in nearby Nauen.) No identifications it wants reception reports, DXers complain here, but on this frequency it is unmistak- that QSLs are few and far between. able, particularly during the later afternoon Most of the stations, though, are good and around midnight in the U.S. verifiers. One of the best -with a sharp Halfway around the world is VNG, the QSL to boot-is Japan's JJY. Recently, this time station of the Australian post office service of Radio Research Laboratories in in Melbourne. It identifies by voice -and in Tokyo has been heard through WWV on English, happily enough -on the hour only. 15 MHz during our late afternoons. (Continued on page 109)

Australian Post Office

OCTOBER -NOVEMBER, 1969 51 You get more for your money from NRI- America's oldest and largest Electronic, Radio -Television home -study school

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52 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER BECOMES AN ABSORBING GET A FASTER START WITH NRI'S LEARNING NRI TRAINING KITS NEW EXCLUSIVE ACHIEVEMENT KIT ADVENTURE WITH learn than by doing? NRI The day your enrollment is received your What better way to and perfected the "home lab" tech- Achievement Kit will be on its way to you. It pioneered nique of learning at home in your spare time. contains everything you need to make an easy, You get your hands on actual parts and use fast start in the Electronics training of your them to build, experiment, explore, discover. new starter kit is an choice. This attractive, Electronics come alive! NRI invites compari- introduce you to outstanding, logical way to son with training equipment offered by any home -study the way NRI teaches it ... backed other school. Begin NOW this exciting, practi- by a dedicated staff and the personal attention cal program. It's the best way to understand you should expect of a home -study school. It the skills of the finest technicians -and make is your first special training aid ... designed their techniques your own. Whatever your rea- to make your adventure into Electronics ab- son for wanting to increase your knowledge of sorbing, meaningful. Your Achievement Kit Electronics ... whatever your field of interest contains your first group of lesson texts; rich ... whatever your education ... there's an NRI vinyl desk folder to hold study material; the instruction plan for you, at low tuition rates to industry's most complete Radio -TV Electronics fit your budget. Get all the facts about NRI Dictionary; valuable reference texts; lesson training plans, NRI training equipment. Fill in answer sheets; envelopes; pencils, pen; engi- and mail the attached postage -free card today. neer's ruler -even postage. No other NATIONAL RADIO INSTITUTE, Wash- School has anything like it. ington, D.C. 20016. by the Accrediting Commission OVER 50 YEARS LEADERSHIP Accredited Home Study Council IN ELECTRONICS TRAINING of the National

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55 OCTOBER- NOVEMBER, 1969 Code practice occupies sizable portion of Saturday morning ses- sions. Informal gatherings normally begin with Joe tapping telegrapher's key while boys jot down letters they hear. To earn FCC Novice license, boys must pass test showing they can send and receive code at 5 wpm.

`Saturday 6Morning

O This is the world of diodes ... transistors ... toroids. It's a maze of tiny electronic components ... of wire and peri boards ... of telegraphers' keys ... 9 -volt batteries and soldering guns. This is Joseph R. Wasserman'.s 90- minute Saturday morning world spent with a dozen or more (depending on the vagaries of weather, homework, and colds; wide -eyed

Keen ears pick out coded letters as show but steady di -dahs issue from oscillatoe. On:e code has been memorized, boys begin poun- ing out their own messages (photos at right).

56 SCIENcs AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER Concentration is a must when it comes to absorbing cold facts. Boy at left is poring over ARRL's License Manual which lists 50 sample questions and answers would -be Novice may face during his exam.

`Ham -in and quick -to -learn kids from suburban Phil- adelphia. It's a 90- minute world that has a way of stopping the clock, for those 90 minutes more often than not somehow stretch into two or more hours. Joe is a school psychologist (Monday to Friday) with the Upper Darby School Sys- tem (adjacent in Delaware County, Pa.) and a ham radio buff of long standing. And

Solder ng is yet another skill successfully acquired by members of Joe's Saturday Morning Ham -in. Friendly word from Joe encourages do- it- yourselfer to develop sure, light touch.

57 OCTOBER-NOVEMBER, 1969 `8afurday6Nlorning "Ham -in

he has some provocative theories about education as well as a mutual love for his hobby and "his boys." "These kids," he says, "are 10, 11, and 12. Just look at what they can learn about electronics, about circuitry and radio theory once a week in this room. I believe we can teach children more detailed, more difficult, and certainly more useful material of all Two toroids are required for receivers boys kinds at earlier ages." rare building, and they wind them themselves. The LaMott Community Center in Chel- Below, boy samples signals from Joe's rig. tenham Township, Montgomery County, Pa., began sponsoring Joe's class last fall. The youngsters learn the International Morse Code, prepare to take the Federal Communications Commission's Novice Li- cense test, and are building their own transistorized receivers. Just to keep spirits high and to show his Saturday morning Marconis what they may strive to achieve, Joe brings his own transmitter and receiver. The boys have listened in while ham operators around the world have carried on contacts across the poles and over the seas. The talk from Texas, California, Alaska, the U.S.S.R., England, even Nairobi is frequently technical. But Joe's boys understand. Not all, to be sure. But more and more each week. -Joe Gronk

Thrilled with romance of communicating with earth's four corners, boys cluster around Joe's transmitter and receiver. Often, they too manage to take part in exciting world of DX action.

58 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER Science dmi Electr^onics d CHECK

HEATHKIT MODEL IG -28

All -IC Color Bar and

Dot Generator

-28 provides Just as with one of the airlines' claims, Features, Features. The IG dots, there's a "something extra" with the Heath - the usual color generator patterns: lines, kit Color Bar and Dot Generator. In this in- cross hatch, horizontal lines, vertical provides stance that something is extra features and color bar. What's more, it also gray scale, hung on a standard color generator. What for purity adjustment, a "plaid" and hori- they do is make it a lot easier to align a and a 3x3 divide for the vertical TV for darn good color quality; you might zontal lines. cov- say they're akin to the fine tuning adjust- In addition to the tunable RF output an asso- ments common to lab -grade service equip- ering channels 2 through 6 (with signal ment. ciated level control) , there is a video IG -28 is all solid- state, using the output with level control, a 4.5 -MHz sound The front latest in computer type design to obtain the carrier output, a sync take -off on the switches. necessary waveforms. Thing is, the step panel, and the usual "gun killer" new counters and adjustable dividers generally Since some of these features are totally to explain. associated with color generators normally to some of you we'll take time out on a at least an oscilloscope for proper If you look at a color bar pattern require with generator alignment. With the IG -28, how- black -and -white TV, or a color receiver integrated circuit flip -flops and gates the color turned off, the color bars appear ever, these mean that you build it and it works. as shades of gray. Now picture many of Except for the non -critical circuits, such shades of gray running both vertically and pattern as the RF oscillators and modulator, the horizontally so they form a "plaid" IG -28 is all -IC, with printed circuits for of gray scale covering the entire CRT. everything except the front -panel controls. When a color set is properly adjusted Heath Since the ICs are essentially direct coupled (using the test procedure given in the through the printed foils, should any prob- manual), the color gun levels are such that lems arise you simply plug in a new IC (all no color tinting occurs on the "plaid" pat- the ICs use sockets). tern. In short, it makes it easy to adjust as black Even the RF oscillator is made trouble - TV so black and white reproduces

free through use of FUNCTION RF /VIDEO POWER 'SNITCH a printed "tank Large printed -circuit AMP BOARD TRANSFORMER' coil." Rather than board in IG -28 con- rely on the usual tains all electronics type of wire coil, except RF oscillator which can be dam- and video output am- aged, the IG -28's plifier. All pulse cir- -lock- oscillator coil is part cuits are IC self or gates, of the printed foil ing flip -flops all ICs plug into on the RF printed and sockets for quick and circuit board. And easy servicing. though it appears to be a "wavy foil," it's actually a coil. 59 OCTOBER- NOVEMBER, 1969 OJLZ3 CHECK and white -not B & W with a smidgen of color. A 3x3 divider does what it says -it di- vides the number of vertical and horizontal lines by three, so that only three H and V lines (rather than 8 to 10) appear on the CRT. The intersection of the two center lines represents "dead cen- Attached gun killer ca- ter" on the CRT, and bles have insulation - the reduced number piercing alligator clips of lines is often much that stab through in- easier to use for cen- sulation, making con- tering linearity, and tact but not injuring dynamic convergence wires to CRT color grids. adjustments. A 4.5 -MHz sound carrier is also just what correct component and soldering. it says -a sound carrier for adjustment of If you're careful and make no mistakes sound traps. It also aids in correct frequency in selecting the components, the IG -28 will adjustment of the color bar generator. The work right off the bat, giving you horizontal sound carrier beats with the color carrier lines and an RF output. Then, using the in the TV set to produce a herringbone pat- supplied alignment tool, you adjust the RF tern in the color bars. When the receiver is oscillator trimmer capacitor so the IG -28's properly tuned to the generator, or vice tuning corresponds to the channel selected versa, the herringbone pattern disappears, on the TV. Two quick adjustments bring in indicating correct tuning. If the pattern does the vertical lines, and the IG -28 is ready for not disappear it means the receiver's sound use. carrier trap must be adjusted. (AIl you do A notable feature of the IG -28, by the is adjust the trap until the pattern disap- way, is the assembly /instruction manual, pears.) with perhaps the best written, illustrated, and Assembling The Kit. In addition to the thorough color adjustment procedure we panel controls, for which a wiring harness have seen to date. is supplied, the IG -28 kit has two PC boards: The Heathkit IG -28 Color Bar and Dot a large one for the color generator and a Generator is priced at $79.95; a wired ver- small board for the RF oscillator and video sion is available for $114.95. For additional output amplifier. Much of the assembly in- information write to the Heath Co., Dept. volves nothing more than plugging in the 19, Benton Harbor, Mich. 49022.

, , , , , / , , , , . 1 , , 1 , , , , , , , , , 11111 111111111 , 11111, , , 1 , , , , , 1 , 1 , , , , , , , , 1111 , , 111, , 11111111 , 11 , 11 , , , , , , , 111 , 1 , 1 1 1 , , , 1, , , , , , 1111, , , , , , , , , 111 . , , , , , , , , . , 11 1111111111 1 1 , 1 , , , 1 , 1 , 11 11111, , 111 1111 111 , 1111111 , 111 , 11 , 1 , , 1 1 1 1 1111 1111 1 1 1 1 1 . . , , , 1111 , , , , , , , 111111 , u , , , , , , , , , , , , , , , , , , , , , 111 , , , 11 , , 111111111, , , 11 , , , , , , , , , , , , 1 , , , , , , , , , , , 1 , 11111111,, , 111 Little Annie Fanny Most everyone's aware of the role computers play in the design of Detroit's cars. Not so well known is the fact that some computers can all but outpaint Picasso -if, that is, they're properly programmed. The fey and fetching Little Annie Fanny you see at left is the work of a CalComp 563 plotter, programmed in this instance by Al Bianucci, a night operator at Chicago's H. W. Lockner, Inc. Al, it seems, found himself with next to nothing to do, so he digitized x and y coordinates corresponding to Annie's fanny et al. Result was Annie herself, all 42 -30 -36 of her.

SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER SnlFe MOVING

VANE Ílilo

1 \1 ,, .% AMMETER

Easy to build -works on AC and DC by Charles Green, W6FFQ in a plastic the first electric indicator was meter components housed When this article are made by Hans Oersted in 1819 "P" box. Included in help you better under- of a magnetic compass and some experiments to out vane action of this wire, he could not have imagined that stand the repulsion that are its direct type of meter. millions of meters Fig. would be in use wherever Vane Repulsion Experiments. descendants used in one -cost rugged indicator is required. 1 shows the components a low be performed to For example: as an ammeter in an au- experiment that can show how iron vanes move by magnetic tomobile. hookup The iron vane electrical meter (am- repulsion. In our experimental coil is made by meter or voltmeter as it's called today) shown in the photo, the winding 200 turns of #22 en- is made in two general types: the polar- random magnet wire on a 11/4-in. diam- ized vane type -a magnet or an iron ameled form, about 1 -in. moving in a magnetic field, or, eter cardboard coil vane form can be made repulsion vane type-two iron vanes long. This cardboard the cardboard wound around repelling each other in an induced by cementing 11/4-in. diameter. Use magnetic field created by the current a bottle having hold the wire in place being measured. plastic tape to flow coming out of the Our project uses the repulsion vane and leave 10 -in. leads about 1 in. of the enamel principle in an easy -to -build iron vane coil. Remove each lead. ammeter. This project will provide the from the end of clean tin can to make reader the opportunity to combine edu- Next, cut up a 1 pieces. These will be- cation with the fun of building. This two 11/2 x /2 -in. iron vanes in this experiment. ammeter indicates from 0 to 1 come the simple is made from AC or DC. A solenoid, two Make sure the tin can ampere, not from aluminum. sections of a tin can, and a rubber band sheet iron and about 1/2 -in. from (in lieu of the conventional metal pivot Bend each iron piece angle. and spiral spring) are the essential one end into a right

61 OCTOBER -NOVEMBER, 1969 MOWING VANE AMMETER

Fig. 1. Vane repulsion experiments demonstrate basic operation of moving -vane ammeter. Circuit works with 6 -V battery or filament transformer.

Then make two 1 x 1 x 1/4-in. wood blocks, and place them under the coil form about 3/4 in. apart, as shown in the photo. Place the two sheet iron vanes inside the center of the coil, with the longer ends upright, and about t/s -in. apart. Make sure they do not touch the wood blocks. The small 1/2 -in. bends should be in the clear space between the blocks. Connect the coil leads to a knife switch, and a 6 -volt battery. Polarity isn't important, as the coil will work with the battery connected either way. See Fig. 2. Close the switch and note that the two iron vanes repel each other. This is because back easily. Mount the moving vane on the the magnetic field of the coil magnetizes rubber band about 1/2-in. down from the each iron vane with the same magnetic po- top of the bracket, by bending a I/s -in. lap larity; both north ends of the vanes are ad- of the bracket end around the rubber band. jacent to one another, as well as both south Mount the bracket and the fixed vane in ends. This is the reason why they repel one the bottom of the plastic box as shown in another. Fig. 3 explains this action. Fig. 5. Before tightening the mounting Repeat the experiment, but hold one of

m11: Ill the vanes with a wood pencil (or other non- ,,,,,,,,,,,,,,,,,n , ,, ,,,,,,,,, ,,,,,,,,,,,,,::::::::::,,:n1/m1111:n:::::nm,n:m1nmm,nm11m11m: magnetic item) so that it does not move. Observe that the free vane is still repelled by the fixed vane. It is this action, with one fixed, and one moving vane, that is used in iron vane meters. Disconnect the battery, and replace it with a 6.3 -V transformer (as in Fig. 2). Repeat the previous experiments with the transformer replacing the battery in the circuit, and observe that the iron vane is repelled in the same manner with AC as it is with DC. Even though the AC changes its direction of flow, the magnetic fields still mag- netize the iron vanes in a similar manner. Building the Meter. The iron vane ammeter is built into a 4% x 35/s x l t -in. plastic box supplied with a clear plastic lid. Use the same coil wound for the vane experiments for this meter unit (see the ammeter assembly drawing). Start construction by making the vane bracket out of 0.05 -in. or heavier sheet aluminum. Make the iron vanes from tin can sheet metal as indicated in Fig. 4. Basic structure of moving -vane ammeter is Use a rubber band that fits snugly over the shown in photo above and in detail draw- bracket as shown, but not too tightly. It ing at right. Text describes how unit is should be able to be twisted and then spring calibrated for both AC and DC readings. ,:1/1111:::um111111:w::m111:::11:::::::0111:::::::11: n11:111:111:m1111u111111::111/m:::11::iii:imi:n...m 11 .11:11::111:1:::1:,::::iimn,11:m11:1 m11:::::::m::::nunumnnnn:ns 62 SCIENCE AND ELECTRONICS, formerly RADIO-TV EXPERIMENTER TYP. REPEL la BRACKET I" DETAILS EC= #27 DRILL ") 1 *' APPROX. L5" THICK ALUMINUM

48011 SEE DETAIL ABOVE REPEL of hookup, iron Fig. 2. Because of nature BEND OUT ANO FOLD regard- lf" vanes will always repel one another OVER RUBBER BAND of battery polarity. If desired, 6.3 -V :'BENT less BI. filament transformer (Ti) can replace

RUBBER ATTRACT Fig. 3. Vanes BAND one MOUNTED can attract FIXED VANE another only VANE DETAIL DETAIL when polarities MOVING Here, vane, REPEL differ. Fig. 4. Details of bracket, moving are 0.05 - polarities and fixed vane. Bracket is made of same, can. always in. aluminum strip, vanes from tin -- so vanes repel.

of the box. Position it as shown in the shift the rubber band so that the tom screws, drawing of Fig. 5. top of the moving vane is even with the top Install Fahnestock clips on the plastic box of the fixed vane. Make sure that the rub- as shown and connect them to the coil leads. band is in the center of the bracket. ber the coil leads to the sides of the box out the bottom of the left side of the Dress Notch and hold the leads in place with a drop of coil form so that it will fit over the bracket bot- cement. (Continued overleaf) base, and cement the coil form to the

MM,,,,,,,,m,,,, 6.,,.Mm,,,,,,Mm,,,M.n,,,,nm,,,inmmM,,,,,,,,,M,HMMM,n,,,.M.I,,,, oILM,uR,,,,,,,UMMUM,,,,,,, MMU,, M,.MMWMmM,,,,,,, FAHNESTOCK CONNECTORS

PARTS LIST FOR SN /FE MOVING VANE AMMETER 3 -6 -V batteries 1 -in. Cardboard tube, 11/4-in. diam., 1- tube long (or cardboard sheet to make SEPARATE -see text) copper wire 1/4 lb.-#22 enameled ACALIBRATIONS 2- Fahnestock clips 4% x 35/e x 11/2 -in. 1 -"P" plastic box, Shack 270- WOOD BLOCK with clear plastic lid (Radio 105 or equiv.) POINTER (SEE vane suspen- 1 rubber band for TEXT) WIRE -Heavy sion (see text) SOLDERED TO potentiometer MOVING VANE R1- 200 -ohm wirewound (Mallory MR -200F with MR -1250 shaft,

(COIL (SEE TEXT) or equiv.) T1- Filament transformer, 6.3 -V, 1 -A 1 wood block FIXED VANE 1 -3 x 2 x -in. Misc.-Tin can (iron only -see text), 0.05 - DC am- MOVING VANE in. or heavier aluminum strip, meter (0 -1A), AC ammeter (0 -1A), rub- BAND RUBBER feet, hardware, solder, etc. (VANE SUSPENS- ber ION CENTERED IN COIL)

VANE SUSPENSION MOUNTING BRACKETS

11 111I111111M1111111111111111III.1111111, 1 .,.,1111111111111iiiiiiiiiii1111 1.1 iii. 1.1111.,1111111,1111111111111,11111111,11111101111110 63 OCTOBER-NOVEMBER, 1969 DC AMMETER MOVING VANE AMMETER

Cement the scale, drawn on a sheet of 18V paper, to a block of wood, 3 x 2 x 1 -in. The wood block is bolted to the box bottom with two sheet metal or wood screws, positioned 200n as shown in the drawing. Screw small rub- RHEOSTAT ber feet on each corner of the box. Fig. 6. Hookup for calibrating Make a pointer for the meter from a moving- vane ammeter for DC. See text for straightened length of #22 enameled mag- details. net wire, and solder one end to the moving vane as shown in the photo and drawing. AC AMMETER Do not use too much heat as heat can dam- T1 age the rubber band. Bend the wire to make a pointer for the meter scale and cut off the excess wire. The pointer is about 23 -in. long. Place a small drop of cement inside the coil form to act as a vane stop and pre- 200n vent the pointer from hitting the side of the RHEOSTAT box cover. Make sure that the pointer and vane swings freely and returns to a zero Fig. 7. Filament transformer and AC am- point. meter are required for easy AC calibration. Calibrating the Meter. You will need pointer by bending the top both a DC and an AC meter having 1 -am- of the bracket. pere ranges; a 200-ohm, wire -wound rheo- Adjust the rheostat to maximum resist- stat; and AC and DC power sources. Three ance and connect it in series with the cali- 6-V batteries will serve as the DC source brated DC ammeter, 18 -volt battery and and a 6.3 -V, 1- ampere filament transformer the iron vane meter as shown in the circuit will do for the AC source. of Fig. 6. Adjust the rheostat and calibrate Before calibrating, draw an arc on the the iron vane meter according to the DC meter scale and establish a zero point. The ammeter readings. Note that the iron vane meter will have separate AC and DC cali- meter will not respond near the zero posi- brations as shown in the photo and draw- tion. Calibration of our unit was started at ing. If necessary, reposition the meter the 0.3 ampere position and was marked at every 0.1 ampere position to 1 ampere. Now connect the AC ammeter and filament transformer as shown in the circuit of Fig. 7 for the AC calibration. Be sure to set the rheostat to maximum resistance before beginning calibration. We started calibration of our unit at the 0.2 ampere point and continued as in the DC calibration. We used rub -on lettering to make the scale for the best appearance. Operation. The use of a rubber band instead of the more conventional metal pivot and spiral spring makes for easier construction. But temperature changes and sagging and aging rubber may cause the meter indications to vary. The meter will still work as a good indicator for approximate current readings. Try using the ammeter to check the current of household light bulbs. The ammeter, Commercial moving -vane ammeters of yes - together with the vane repulsion experi- ter -year were much like water meters. Note ments, will also make a good science fair that device was accurate only if vertical. project.

C4 SCIENCE A ND ELECTRONICS, formerly RADIO -TV EXPERIMENTER &cience and lectibnics U3 CHECK

EICO CORTINA

Model 3150 im4 ^ `¡ ®, ,O.. .. OP i* Integrated Stereo Amplifier . Or

provides the tape- recorder input. Out- When the original EICO Cortina ampli- switch puts include main speaker, remote speaker, fier was introduced a year or so ago, just headphones, and tape recorder. about nothing else was available that de- Other Controls. Volume and tone con- livered comparable performance at such a are ganged, which means that what you price. But the original Cortina unfor- trols low one channel you automatically do to tunately lacked the punch needed to drive do to

PI and 'the effect of its controls The 3150's frequency response RIAA equalization on 3150 +20 BOOST from 20 to BASS 1. TREBLE was ruler flat +1 20,000 Hz. Bass and treble GNETIC PICKUP INPUT ' controls had fulcrum around 1 -kHz point, with maximum boost and cut of some 20 dB. BASS d TREBLE C U T -.

-20 3K 2011 40 60 80 300 6008001K 4K 6K 00 200 400 10 FREQUENCY Hz)

+2 LOUDNESS CONTOUR, VOLUME CONTROL i OPEN s +1 J 1 '_ N Response at -watt output cen- Es D with tone controls RESPONSE tered was also pretty much = -1 0 H LO CUTOFF f LTERS CONTROLS CENTERED ruler flat. High filter was -2 filter 800 4 16k 13K 203 effective, though low 0in 30 0 1 00 2L ,,,,4 I LK ,I 20 40 proved somewhat broad. FREQUENCY (Hz)

uun wumn.amommilmmnrnmomimumommuumummumumumwuwwnuaml 1uuuuu1uuuuuuuuuuuuiuuuuuuuuuauuuutuuuuuuuuuuuuluuuuuuuunuuuuuuu uu uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuMuuuuu uUuuuu

is provided to high volume the other. A balance control low- efficiency speakers volume; a speaker -power Cortina, for equalizing the stereo levels. Now, a new, high headphones, main that limitation with selector selects either Model 3150, overcomes speakers, or all speakers. of stereo power output speakers, remote 150 watts (IHF) - provide for loudness con- than needed by any speaker sys- Panel switches a lot more /stereo, to -cut, hi -cut, and power; those who don't need the extra tour, mono tem. (For rear apron contains both switched and power the original 70 -watt Cortina is still the non -switched AC outlets. available.) the circuitry is fairly conven- to packing more punch, the Though In addition mono /stereo switch is somewhat also utilizes the latest in high - tional, the 3150 Cortina Reason is that the mono connec- solid -state technology for rock- bottom unusual. power made by parallel- connecting the sig- distortion. The new Cortina offers four in- tion is nal inputs together, rather than the pre- a selector switch handles magnetic puts: outputs. This method avoids the phono, tuner, and auxiliary; a tape- monitor amplifier 65 OCTOBER-NOVEMBER, 1969 thing even remotely resembling a short circuit. And, unfortunately, any load offering fti& CHECK an impedance of less than 4 ohms is going to look too much like a short circuit for com- fort.) crossloading of the amplifiers which often results in increased distortion. (We could SPEAKER TERMINALS not determine any deleterious effects, includ- INPUT JACKS ing increased noise level, caused by the EICO -type connection.) The 3150, available wired ($225.00) or kit ($149.95), complete with wood finish cabinet, uses modular construction; each individual section -preamp, driver, etc. -is on a separate printed- circuit board, and each OUTPUT TRANSISTORS TAPE OUT channel has its own boards. There appear Output transistors are recessed to in heat sinks, be no assembly problems other than the which are themselves recessed to provide usual tedium of plugging many components flat, non -protruding rear apron. Both main into matching holes. and remote speaker terminals (at left) have Performance. their own common Typical of the most mod- (ground) connections. ern solid -state designs, the EICO Cortina Distortion is about as low as can be measured with standard lab -grade instru- PREAMP OUTPUT TRANSISTORS FUSE ments. Total harmonic distortion (THD) at the threshold of clipping was 0.1% at 20 Hz, 0.08% at 1 kHz, and 0.18% at 20 kHz. As shown in our curves, tone -control range is very wide, with almost 20 dB cut and boost at the extreme ends of the listening spectrum. The loudness switch adds about 7 dB boost at 20 Hz. Our curves also show high -frequency cut to be good: only 3 dB down at 7 kHz. The low- frequency cut, however, is a little more broad than usual. This means that a listener would likely notice a slight loss of bass when TONE AMP ORIVER POWER TRANSFORMER the to -cut is used to reduce turntable rumble (though we can't see why Each side of chassis contains printed anyone would circuit connect anything other than modules for single amplifier channel (this is a quality turn- upper side of completed amplifier). Top- table to this amplifier). side also contains power -supply filter, shown The magnetic input equalization is ab- to left of husky power transformer. Even solutely ruler flat, with a sensitivity of chassis is assembled in modular form: front 0.0015 V (rms) for rated power output. (with controls), back, and amplifier base. Hum and noise measured better than 80 dB down, which is absolutely dead quiet at any amplifier is absolutely ruler flat from 20 Hz volume -control setting. to 20 kHz at normal listening levels of 1 How It Sounds. The EICO 3150 watt, and almost is easily ruler flat at the rated power identified as having "transistor sound." Its output of 40 rms watts (sine- waveform) per output is exceptionally channel clean and transpar- into an 8 -ohm load. As with most ent, noticeably so at the higher frequencies solid -state amplifiers, power output varies where the amplifier can deliver some 5% somewhat with load impedance. For the Cor- more than the rated power before clipping. tina, the rated power output per channel is In fact, it is quite something to listen to a 50 watts into 4 ohms and 25 watts into 16 soprano's high C at full power output; few ohms. (Under no circumstances should the other amplifiers can handle it as well as total per channel speaker load be less than the 3150. 4 ohms. Reason is that the 3150, like most For additional information on the 3150 solid -state amplifiers, will attempt to deliver Cortina, write EICO, Dept. T, 283 Malta St., a tremendous amount of power into any- Brooklyn, N.Y. 11207. 66 SCIENCE A ND ELECTRONICS, formerly RADIO -TV EXPERIMENTER 97-cent Hard- Rock Fuzz Box mere pennies Add "Fuzz" to your guitar amp for

by Herb Friedman, W2ZLF /KBI9457

your or just 97Ç you can modify the amplifier of Fpractice, or budget, guitar by adding the hottest For sound going with the hard -rock combos -fuzz. explain. too square to know what fuzz is, we'll those of Fuzz is distortion, out -and -out distortion random the original guitar sound. Unlike distortion, most fuzz effects are accom- the plished by squaring the waveform of guitar pickup, thereby obtaining a husky sound quality akin to that of a saxophone. Most new guitar amplifiers have the fuzz built in, the technical terms for fuzz being harmonic modifier, overtone, or something

67 OCTOBER-NOVEMRER, 1969 TONE CONTROL Hard -Rock RI SI DI, D2 VOLUME CONTROL Fuzz Box similar. Whatever it's caned, it's still fuzz. If the amplifier doesn't have built -in fuzz, the fuzz sound can be added through the use of a fuzz box -an adapter connected between the guitar pickup and amplifier input. Though fuzz boxes provide the con- veniences of adjustable fuzz quality and a foot switch, the price range of $12 to $40 often puts it well outside the budget, particularly for units considered practice or Fig. 1. Parts for fuzz circuit mounted on am- budget units that originally cost less than the plifier panel surrounding existing controls. commercial fuzz box. Well, for you budget - minded people, we offer the 974 Fuzz Box, point, usually across the volume control, actually a fuzzing where the circuit that is built di- guitar signal is approximately 1 rectly into the amplifier (see Fig. 1). to 3 volts. Therefore, the diodes will clip What Is Fuzz. As shown in the schem- that part of the signal waveform that ex- matic, the fuzz circuit is nothing more than ceeds 0.5 to 0.7 volt. RI increases the con- a diode clipper (D1 and D2), a switch to duction voltage, allowing the user to set the turn it on and off (S1), and a depth control clipping level anywhere from just peaks (R1) that sets the degree of fuzz effect. of the waveform (slight fuzz) to the husky The on -off switch can be combined with the sound obtained when the diodes are returned control, and if you use the recommended directly to ground. The photographs clearly source for parts the whole bit will cost 974. indicate the effect of the fuzz circuit. Fig. 2 If you want to build a super- deluxe version shows a sine- waveform simulating the guitar having a separate on -off switch it may run sound with no fuzz-S1 open. Fig. 3 is the about $2. When a separate switch is used fuzz circuit cut -in, with R1 at almost full the setting of the depth control is not af- resistance (note that the waveform is just fected as the fuzz is switched in and out. slightly distorted). Fig. 4 shows the high How It Works. Diodes D1 and D2 are degree of distortion obtained when R1 is set the silicon type, requiring approximately 0.5 to zero resistance -full fuzz. to 0.7 volt before they conduct. The fuzz The scope pictures have been adjusted to circuit is connected into the amplifier at a be almost equal in size for clarity of illustration. Actually, as you would expect, the MIC PREAMP fuzz circuit causes a loss in sound level of up to 6 dB, depending on the degree DC BLOCKING CAPACITOR of fuzz. (SEE TEXT) This is generally no problem since most

1V OR MORE guitar amplifiers have much more than 6 dB 2ND AMP SIGNAL reserve gain. VOLUME When fuzz is added to transistor ampli- CONTROL I _ Left, fuzz circuit GUITAR r- - added to vacuum tube TO OUTPUT amplifier. Right, fuzz circuit to use COLLECTOR (PREAMP I if your amplifier is transistorized. CIRCUIT INPUT) 01 PARTS LIST FOR 97C FUZZ BOX C1- 100 -uF capacitor (see text about voltage D2 RI rating and when required) (SEE TEXT D1, D2 -Low signal voltage silicon diode ABOUT POLARITY (see text) (Lafayette OF Cl) 1976001 or equiv.) C1 i 1 R1 /S 1- 10,000 -ohm miniature potentiometer R1 i S1 with spst switch (Lafayette 3277364 or equiv.) (same less switch -see text -La- L S1 fayette 3277356 or equiv.) CIRCUIT REQUIRED FOR FUZZ ADDED 51 -Spst toggle switch (Lafayette 3473301 or TRANSISTOR AMPLIFIERS TO GUITAR AMP 9976162 or equiv. -see text)

68 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER fiers the circuit must be modified slightly by inserting a 100 -uF capacitor (C1) in series with the arm of Rl, as shown in the schematic. Voltage rating of Cl should be equal, at least, to the voltage to which D1 and D2 connect. Polarity connections of C 1 are determined by the amplifier circuit voltage at Dl -D2 (usually + for npn and - for pnp transistors). When the voltage is positive, Cl's positive lead is connected to the arm of R1, or, if voltage is negative, Cl's sine wave output of guitar amplifier the Fig. 2. Undistorted negative lead is connected to simulating guitar sound with no fuzz added. it. Where to Connect. The fuzz circuit must be connected into the amplifier at some point where the signal level exceeds 1 V. This is normally after the microphone preamplifier, across the volume control. (If tone controls are also connected across the volume control they are ig- nored.) If the volume control is in the circuit before the microphone preamplifier rather than after it (which would not be normal), or if it follows a second amplifier stage, connect the fuzz after the first amplifier, following of guitar amplifier with fuzz in, R1 at Fig. 3. Output the plate DC blocking capa- nearly full resistance. Note waveform slightly distorted. citor. Do not connect the fuzz to the wiper arm of the volume control as this will disable the volume control, causing the volume control to affect only the degree of fuzz. Similarly, don't try to get more fuzz by connecting to the grid of the output tube as this will sharply reduce the overall amplifier gain, and the volume control again will affect only the degree of fuzz. The best location for the fuzz circuit is at the point where the signal voltage just exceeds 1 V, usually after the microphone preamplifier. amplifier with maximum fuzz, R1 Fig. 4. Output of guitar In transistor amplifiers you set to 0 resistance. Note high degree of distortion. 69 OCTOBER- NOVEMBER, 1969 amplifier ground. There usually is a ground Hard-Rock wire connecting the ground lug of the volume control to the input jack ground. If the volume control is grounded to the chassis Fuzz Box through its mounting bushing (no ground bus wire), connect the fuzz ground from Si will most likely find 1 the -V signal level to the volume control ground at the volume point is the collector of the second transis- control-do not ground the fuzz just any tor. Connect the transistor -version fuzz old place on the chassis. Nine times out of (with Cl) to the collector of this transistor. ten it doesn't matter where the fuzz is Placing the Parts. Try to keep the fuzz grounded, but yours might be the tenth case. circuit away from power leads because it is Using the Fuzz. When Si is open (fuzz a relatively low level circuit, and is prone to off) the amplifier will function normally. hum pickup. It is better to locate it as close With Si closed (fuzz on) the fuzz effect as possible to the volume control or asso- can be varied from full on to fuzz ciated circuit. oft, as A typical installation is shown determined by RI's setting; full resistance in the photographs. A miniature potentiom- is little or no fuzz, while zero resistance is eter (R 1) is used to squeeze in between maximum fuzz. Do not expect existing components. the rough, harsh fuzz associated with add -on fuzz boxes. The 97 Fuzz simply cannot generate that much distortion. You'll get a definite husky sound, quite different from the normal guitar sound, but not quite the rough effect of an add -on commercial unit. Since the fuzz sound is really harmonics created by distorting the original waveform, the amplifier must be capable of passing the harmonic frequencies, for if the harmonics are reduced, or filtered out completely, the final sound won't be much different from the normal guitar sound. Therefore, when using the fuzz make certain the amplifier's tone control -which is usually of the highcut type -is wide open to pass all of the high Using a center punch to mark panel before frequencies. After a little drilling prevents possibility practice, of course, of bit slipping you can use the tone and inadvertently scratching panel. control to get subtle shading of fuzz tone quality. About the Parts. D1 and D2 are the First step is to drill the holes in the panel. cheapest small- signal silicon type; To avoid usually shaking the amplifier to pieces with sold in packages of 10 for about an 90 cents. electric drill, leave the amplifier mounted R1 is a "dime size" transistor potentiometer in its case for support and center punch the of 10,000 ohms, available with a switch (La- panel (so the drill doesn't walk into other fayette 32T24O5, 790 or without a switch components). Then drill the mounting (Lafayette 32T7356, 590. If you use a sepa- hole(s), preferably with a slow speed drill. rate on -off switch for SI you can buy a stand- The slower the speed the lower the vibration. ard size toggle type (Lafayette 34T33O1, Whether you use a separate on -oft switch, about 50e) or a subminiature type (Lafay- or one mounted on the back of 121, try to ette 99T6162, price around $1.50) if space connect the ground end to the low level is at a premium.

73 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER Science and ¶lectrônics a [3 CHECK

UNIVOX

Super -Fuzz

Guitar Fuzzbox

simulates a frequency shift. Imagine, if you can, a guitar sound so with in a manner that other hand, the Univox can be set it, now, so far out, that it can't be put on On the so a slight frequency That's just what you get with a to automatically trigger a record! each note that cre- Super- Fuzz ultimate in a gui- shift at the beginning of Univox -the "blue note" sound. End tar fuzzbox. ates a continuous as though the vibrato handle Unlike conventional fuzzboxes, the Uni- result sounds been moved at the beginning vox Super -Fuzz neither distorts the wave- had actually clipping signal peaks, nor generates of each note! form by effect. The Univox kickback oscillation that causes a And that's only one a slight from standard fuzz peak burst of distortion. Instead, this un- can generate everything impulse waveforms that can be usual unit generates almost completely new effect to the finest of amplifier equip- sound waveforms which are triggered by handled by only so steep they couldn't be the basic guitar waveforms. And the sound ment- waveforms stylus even if they could no longer resembles that of a guitar. Rather, traced by a phono simulate many new ethereal instru- be cut on disc. it can Some typical effects ments depending on the setting of the Uni- Picture Gallery. obtained are shown in our wave- vox's controls. that can be These were made using For Vibrato. For example, with a form photographs. V Since guitar vibrato rapid variation in pitch a sine -waveform test signal. guitar, -a - sine -waveform, only be obtained by changing the ten- sounds aren't necessarily can obtained surpass those sion on the guitar strings; this is normally the actual effects accomplished by physical movement of a shown in our photos. 1 600-Hz reference, a pure guitar's vibrato arm which is mechanically Fig. is our Fig. 2, the Univox No. 1 connected to the guitar strings. The closest sine -waveform. In slightly opened, distorting the you can get electronically is wah -wah, a fuzz has been in a typical fuzzbox and simple system whereby a foot control causes basic waveform as second harmonic (note 6 an oscillator to trigger on guitar waveforms also adding some

Fig. 2. With No. 1 fuzz slightly open. Fig. 1. Pure, 600 -Hz sine -waveform. 71 OCTOBER -NOVEMBER, 1969 even more No. 2 fuzz with multiple harmonics, distorted basic tone, and impulses ftIEI3 CHECK at slightly lower than the second harmonic frequency. The sound here is unbelievably cycles rather than 3) . Increasing the No. 1 weird. And it is at the point where the im- fuzz effect gives distorted second harmonic pulses are generated that the slide tone ef- as shown in Fig. 3; and even more No. 1 fect is obtained as the impulse starts at fuzz gives a a severely distorted second har- slightly lower frequency and slides monic, up about producing a high order harmonic 1/4 to 1 tone. fuzz tone (Fig. 4). These are all the effects Fig. 7 is maximum No. 2 fuzz. Note which give that the so- called saxophone guitar the waveform is not blurred because sounds. of poor scope sync. Rather, the sound Fig. is harmonics, 5 is a slight amount of No. 2 fuzz, added to harmonics, creating more harmon- which virtually destroys the guitar's normal ics, on top of the distorted basic frequency, sound and makes it multiple harmonics and with impulses àdded. It's an some unbelievable basic original frequency. Fig. 6 shows effect somewhere west of Pepperland!

.fil r fln'' UUv LIu uu Li

Fig. 3. With 1 No. fuzz more open. Fig. 6. With No. 2 fuzz more open.

Fig. 4. With 1 No. fuzz fully open. Fig. 7. With No. 2 fuzz fully open.

As shown, the Univox Super -Fuzz gets its myriad effects from only two of three controls, for one is a BALANCE control and contributes nothing to the effects. The FOOTSWITCH on the top cuts the superfuzz in and out. The BALANCE control sets the superfuzz level so that the amplifier's output sound level is the same with or without fuzz. The EXPANDER control carries the power switch and provides the desired fuzz depth; the more it is advanced the greater the degree of fuzz effect. Fig. 5. With No. 2 fuzz slightly open. (Continued on page 107) 72 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER TAllEST

LOWER Tallest self -supporting antenna tower in the U.S. was recently erected by the Monroe County Elec- tric Co -op just north of Waterloo, Illinois. Interestingly enough, the Union Metal Manufacturing Company in Canton, Ohio has fabricated a series of monotube self -supporting antenna poles from 25 feet through 200 feet since 1941. But the 225 -ft antenna pole in our photos is the first to be manufactured in this series and the first one erected in the U.S. L.V. Hard, manager of the Coop- erative, said this pole was ordered to complete his excellent communications hookup. His system consists of a Motorola base station and six Motorola mobile units, broadcasting on 158.78 MHz and covering three counties with a range of '35 miles. Prior to its erection, the antenna

OCTOBER-NOVEMBER, 1969 Below, left, ten 80 -in. anchor rods made up pole's anchorage. Below, right, Alois Luhr TALLEST TOWER (no hat) checks pole's 16 -ft -deep foundation.

pole was assembled and painted, and the aircraft warning lights installed and wired. The three lower sections had the wire rope slings in place with the come -a -longs (coffin hoists) in tension. Before raising the pole into position, a tag line was fastened at the top of the pole and another one about halfway down. Taking care to protect the aircraft warning light at the top of the pole, workers fastened the wire sling at the balance point of the pole. Not entirely self- supporting, the antenna pole is comprised of 13 tapered tubular sections telescoped together to a t.Ital length of 225 ft. The butt tubular section is 24 -in.

Breathtaking part of 20- minute erection time came as 225 -ft pole was progressively raised higher and higher toward true vertical. As safety precaution, steel cable was placed around pole near base and held taut by winch truck. Erection crew found plenty of opportunity to put their two -way radios to good use during course of actually raising 26,850 -lb. tower.

74 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER around joints were in Wire rope slings with come -alongs and heavy copper wire checked. Crew of place at start. At first lift, entire antenna pole was carefully at top of pole. Monroe Coop took special care to guard aircraft warning beacon

in diameter, while the very top is a mere 3.8- in. in diameter. L. E. Dechant of Dechant Electric Ser- vice in Belleville, Ill., supervised installation of the coaxial cable and antenna at the top of the pole. Equipped with Motorola two - way radios to talk to the ground, one of Dechant's men and a member of the Co- operative's crew climbed the pole to attach the antenna and coaxial cable. Addition of the antenna gave the pole /antenna combo an overall height of 247 ft. The Motorola base station was moved from its former location in Waterloo and on the air by 4:30 p.m. of the same day.

bolts before pole Coop engineer Wiley Jones (sweater) checks pole position over anchor anchor bolts, workmen then is lowered into final position. Once pole had been seated on -high structure was adjusted first leveling nuts, then anchor nuts to ensure that entire 247 -ft position. both adequately secure and accurately locked in true 90- degree- from -horizontal 75 OCTOBER- NOVEMBER, 1969 AM RAFFIG

E wsnos by MARSHALL LINCOLN Watch Not, Have Not

SWLing generally is thought of as being to get these intruders moved with FCC help. completely separate from ham radio. Separ- The Intruder Watch corps has grown to ate it is, though there's a form of this ac- include several dozen dedicated hams who tivity that has become very important to spend a few hours each week tuning across hams. The SWLs in question are hams the ham bands searching for signals, mostly who're active in a specialized form of SWL- from foreign broadcast stations, that have ing. They perform a vital service for all moved in and set up shop. Once these are of us., located, their frequencies must be deter- Though these SWLs scan the ham bands, mined and the stations identified. Then a they're mainly interested in finding non - written report is made to ARRL head- hams! They're not looking for bootleggers quarters. in the usual sense -but they are looking for These reports from Intruder Watchers all radio stations which don't belong on our over the country are dovetailed together and frequencies. forwarded regularly to the FCC. Then, These SWL -hams are officially known as either the FCC or the State Department members of the Intruder Watch. This is a makes official contact with the offending ham activity which is little known, but vi- stations or with their government authorities. tally important to all of us. It was organized From this procedure, which is unavoidably about five years ago by the ARRL to pro- slow and cumbersome at times, has come vide a systematic, effective way of spotting considerable relief from foreign broadcasters commercial stations which operate illegally who have created undue interference on the on ham frequencies. It also provides a means ham bands.

Among the hams who help guard our precious frequencies against commercial stations moving in are two Intruder Watch listeners, Dr. William W. McGrannahan, KOORB, Kansas City, Mo. (right) and Elmer P. Fruhardt, Jr. W9GFF (left), Chicago, Ill. They are among the dozens of hams over the country who regularly submit reports of commercial stations they've heard interfering with legal ham operations. It is through this group's actions that it is possible for our government to take action that will stop this infringement on overcrowded ham frequencies.

76 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER Never before has the It's important that such complaints be our brother operators. such a criticism of the processed against these intruders. If their FCC had to make intrusion on ham frequencies goes unchal- Amateur Radio Service. has been complimentary lenged, these broadcasters can claim in the Generally, it our service. But now, future that no one objected to their use of about our actions and are beginning to ham frequencies and that they therefore the federal rule makers of those in our midst should be allowed to continue to use them frown at what some the once -proud world legally! are beginning to do to This can happen because of a loophole of amateur radio. has done much listening in in the international ham regulations: some Anyone who marvel that the FCC frequencies are reserved world-wide for ham recent years can only this before. But but other portions of our bands are hasn't complained about use, the wall. The with various commercial users in now the handwriting is on shared midst fel- other parts of the world. If there is no "criminal element" in our -the language complaint that these commercial sta- lows who carry on with dirty official of more tions interfered with legal ham operations, and roughhouse manners -consists cases. Fact is, then the commercial boys can legally con- than just a few scattered enough to deserve tinue to use ham frequencies. That would they've become numerous by the government be a sneaky way to steal some of our fre- official condemnation we're supposed quencies! agency that writes the rules Bandits In Our Brotherhood. The FCC to live by. for doing a has confirmed its agreement in principle with Formerly hams were noted As the concern expressed in this column some good job of policing their own bands. be at a time ago regarding the guttersnipe behavior a result, FCC enforcement could could be pretty of a growing number of ham radio operators. minimum and still our bands behavior. But In a recent report of its own activities, clean in terms of individual neces- the FCC had this to say: "The past year has now sterner measures may become their own house. shown a significant trend toward increased sary unless hams can clean on- the -air feuding and use of questionable There's no room in our wonderful hobby language in a radio service which histori- for those who have no respect for one an- cally has prided itself on cooperative self - other or for decent public conduct. regulation. Limited manpower has prevented Remember, even in the privacy of your attention to any but the most flagrant cases. home, you're on public display every time Approximately 2800 violation and advisory you key up the transmitter and talk into notices were issued to licensees during the the mike. Anyone can be listening just as year." if you were down at the courthouse square If some of us tend to shrug this off, it on a soap box. should be emphasized this is a pretty serious To protect our hobby and our future op- condemnation of the behavior of some of (Continued on page 108)

77 OCTOBER- NOVEMBER, 1969 By ARTHUR S. COOKFAIR

. , A 1111111...... ' . FAMOUS PAENTS No. 763,772 A THE FOUR- CIRCUIT 1 (i TUNING PATENT

In the year 1901, accepted scientific theory radio waves, which travel in a straight line, said that wireless communication must would not follow the curve of the earth, be limited to about 165 miles. When Gug- but would go off into space. Despite the lielmo Marconi announced his plan to trans- gloomy forecasts of failure, Marconi suc- mit signals across the Atlantic, the greatest ceeded in sending radio waves across the scientific minds in the world said it couldn't Atlantic Ocean. Explanations were quick to be done! follow. The following year Sir Oliver Heavi- But the 26- year-old engineer went ahead side and Arthur Kennelly showed that radio and invented a better "wireless" system and, waves are bounced back to earth by an ion- on Dec. 13, 1901, used it in the first trans- ized layer in the stratosphere (the "Heavi- atlantic transmission. He had done the thing side- Kennelly layer "). that couldn't be done. Marconi's achievement was acclaimed by The irony of it is that 40 years later the the scientific world. But it's one thing to Supreme Court of the United States found convince a group of scientists and quite an- his claim to that accomplishment invalid. other to convince a group of lawyers and The pessimistic predictions of the turn -of- judges. In the legal world, the young Ital- the- century scientists were based on the line - ian's troubles were just beginning. o} -sight theory. According to that theory, Marconi patented his improved radio system in 1904 (Patent No. 763,772.) Because his system required two tuning circuits in the fl I' transmitter and two in the receiver, the patent became known as the "four- circuit tuning patent." Others were quick to use Marconi's system (without permission) and the patent gy2 became involved in one law suit after another. While the rest of the world acknowl- edged the inventor's accomplishment, lawyers and judges continued to argue about it. (Continued on page 109)

Marconi's four-circuit tuning patent filed on June 28, 1904 illustrated circuits for both his transmitter (Fig. 1) and his long -wave receiver (Fig. 2).

78 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER PERPETUAL MOTION FREQ STANDARD by Ron Michaels Bach or Rock ... no matter what kind music you make, you'll make it better if the instrument you play is in tune. Obviously, if this statement is true for one instrument -and who will dispute it -it's unquestionably true for an instrumental group. Trouble is, tuning up an assembly of different instruments can be a problem: none of the standard assortment of tuning aids (pitch pipes, whistles, etc.) is really very accurate. On the other hand, the tuning fork, a universal standard for musical tone, produces a very low -level output that's hard to work with in a large room, unless it's held very close to

OCTOBER- NOVEMBER, 1969 79 FREQ STANDARD your ear. For this reason the fork must be passed from player to player -a time - consuming job. Our amplified electronic tuning fork oscillator will lick this problem. The heart of this unit is a conventional tuning fork, that produces a pure sine wave output that is absolutely accurate. Its electronic circuitry is arranged so that the tone output is continuous and at sufficient volume from the built -in loudspeaker for most group applications. It's not necessary to repeat striking Completed perpetual motion Freq Standard. it during tune -up -time. That's on /off switch Si at lower right, only How It Works'. Ql, a Darlington ampli- control to be found anywhere on unit. fier, is connected as an oscillator that, sus- piciously, looks like any conventional feed- The tuning fork vibrations induce a sinu- back oscillator configuration. And so it is- soidal current flow in coil L2, connected to with one major difference: the collector and the base of Q), which is amplified by the base inductors (coils L1 and L2) are coupled transistor and fed through collector coil L1. via together the tuning fork. In essence, this This produces a magnetic field around L1 circuit can be compared to a dog chasing its that is sinusoidal, forcing the tuning fork own tail. to vibrate. Because the fork vibrates at this

1 ,,,

TUNING FORK T1

An SPKR

Schematic reveals Freq Stan- dard's simple but highly ac- C2 curate circuit. Mechanical tuning fork controls 01's 10NF frequency of oscillation; audio tone appearing at 01's base is then amplified and 01. 02. 03 fed to either J1 (for further BASE amplification) or direct to CONNECTIONS Freq Standard's speaker. PARTS LIST FOR PERPETUAL MOTION FREQ STANDARD B1 -9 -V battery (Eveready 266 or equiv.) R5- 1800 -ohm, 1/2 -watt resistor C1- 250 -uF, 12 -V electrolytic capacitor S1 -Spst toggle switch C2- 10 -uF, 12 -V electrolytic capacitor T1- Output transformer: 1000 -ohm pri.; 8 -ohm J1-Open-circuit phone jack sec. (Lafayette 3378550 or equiv.) L1, L2 -See text 1- Tuning fork (see text) Q1- 2N5306 Darlington Amplifier (GE) 1- 2y2 -in., 8 -ohm speaker (Lafayette 9976038 Q2, Q3- 2N5172 transistor (GE) or equiv.) 1000 -ohm, R1- 1/2 -watt resistor Misc.-Aluminum minibox, 1/4 -round wood mold- R2- 220,000 -ohm, 1/2 -watt resistor ing, epoxy cement, battery strap, tie strip (4 R3 -820 -ohm, 1/2 -watt resistor J lug), perfboard and push -in terminals, wire, R4 -560 -ohm, 1/2-watt resistor solder, hardware, etc.

ili,Iiiiii,,,,,111111,1,,,,111 ,i1,,,,,,,. .., 11,111111,,,,,,,,,1111,1111111111,,,,11,1,11111 1 1 1,1,,11111,11111111,1111111111111111f/1111,.1,111111111111111111111 11111111.1r11,.111o111111111111111:11,,,,. 11111111111111T,I1

80 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER fundamental resonant frequency, the output ohm impedance headphone. Each coil frequency is stable and accurate. has an impedance of 1000 ohms - What starts the fork vibrating in the first the two coils are wired in series in the of place? Random electrical noise. The minute headphone case to total the 2000 ohms first unscrew you turn on the power switch, Q 1 amplifies the unit. To remove the coils, this noise which, in turn, starts the fork the hard rubber cap and lift off the thin vibrating. In a few seconds (typically 5 to metal diaphragm (it is held in place by mag- 10) the fork stabilizes at its resonant fre- netic attraction). Remove the two bolts that quency. hold the horseshoe magnet to the coil as- Transistors Q2 and Q3 form a straight- semblies (each coil assembly consists of a forward audio amplifier circuit that drives coil of wire mounted on a right angled pole the built -in speaker. The signal to be am- piece to facilitate its mounting to the mag- plified is taken from the base of Q1, its net). Carefully cut the very thin copper input, rather than its output, because the wires that join the coils together and also sine wave is purer at this point. The trip the wires from each coil to its respective out- through the Darlington amplifier tends to put terminal of the headphone. distort the waveform. Firmly fasten coils L1 and L2, each to a If you desire greater output volume, the separate wooden block, made from 1/4- oscillator output can be fed from J1 to any round wood molding approximately 2 -in. external audio amplifier. long, by means of a wood screw through the Building lt. You must use a steel tuning hole in their pole piece /mounting support fork, so be sure that the one you buy is not aluminum. A magnet tells all. Your local music supply shop will have (or will be able to order) steel forks in a wide range of fundamental frequencies. The fork we use vibrates at 440 Hz (standard A) . However, you do not have to stick with a 440 -Hz fork as any other frequency will work in the device. Thread the end of the fork's stem with a steel threading die. The fork will, in all probability, have a stem diameter of 1/4-in., so that a 1/4 -20 NC die is perfect. This threading enables mounting the fork securely with 1/4 -20 nuts to the alumi-

num s minibox that serves as the chassis /cabinet (as shown in photo) . A secure mount is necessary for proper operation since the fork must be firmly held in place between the two coils. From Phones To Oscilla- tor. L1 and L2 are coils obtained from a Trim 2000-

Freq Standard's mechanical construction is simplified by placing tuning fork in bottom of minibox, perfboard and most related components in top.

81 OCTOBER- NOVEMBER, 1969 FREQ STANDARD

into the wood block. Using epoxy cement, cement the wooden blocks to the base of the minibox, as shown in the photograph. The blocks should be positioned so that the space between a tuning fork tine and the pole piece of a coil is 1/16-in. L2 should be mounted so that it is placed about a coil's length further down the length of its respective tine than coil LI is down its tine (see photo). This positioning will improve signal linearity. Carefully solder flexible, insulated wire ex- tensions to the fine wires of each coil, of View of bottom portion of Freq Standard, sufficient length to dress them away from showing tuning fork, coils L1 and L2, and the fork and long enough to reach a tie wooden blocks which hold them. See text for recommendations re placement of coils. strip. The wire from the coils is very fine and enameled. Be careful in removing the Since AC hum pickup (from adjacent power enamel when preparing the fine wire for lines) is a potential problem, keep all in- soldering to the extension leads. Make sure terconnecting leads as short as possible. An- all the enamel has been removed and the other reason to keep them short is to ensure copper is bright and clean. Handle the fine that they will not droop onto the tuning fork wires with the care you would give a delicate when the minibox is closed. This will affect piece of china; they are fragile, and can be the fork's output. Note: The phasing of the easily broken at the coil bobbin. two coils is important. If you get no tone The balance of the components are from the unit after checking out your wir- mounted and wired on a piece of perfboard, ing job, reverse the connections to either using push -in terminals as soldering points. one of the coils, but not both.

TV's long, long way to Tipperary

It's a long, long way from the Apollo 11's Pacific splashdown point to Tipperary, but Tipperary TV viewers enjoyed live coverage nevertheless. Reason was an unusual furled parabolic reflector antenna which Western Union International used to beam the event to a Comstat communications satellite and thence to TV stations in some 49 countries around the world. The 15 -ft antenna was mounted on gyro -stabilized platform on deck of U.S.S. Hornet and maintained un- erring aim on satellite regardless of motion of ship.

82 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER VOLUME 51, PART 5 WI-111E'S

An up -to -date Directory of North American AM, FM, and TV Stations, including special sections on World -Wide Shortwave Stations and Emergency Stations for Selected Areas

WHITE'S RADIO LOG CONTENTS FOR 1969* Issue Listing Page Feb. /March U.S. AM Stations by Frequency 92 World -Wide Shortwave Stations 107 Emergency Radio Services -Chicago Area 109 April /May U.S. TV Stations by States 92 Canadian TV Stations by Cities 94 Canadian AM Stations by Frequency 95 World -Wide Shortwave Stations 97 Emergency Radio Services -New York City Area 99 June /July U.S. AM Stations by Location 84 World -Wide Shortwave Stations 98 Emergency Radio Services -San Francisco Area 101 Aug. /Sept. U.S. FM Stations by States 82 Canadian AM Stations by Location 88 Canadian FM Stations by Location 88 World -Wide Shortwave Stations 89 Emergency Radio Services -Boston Area 92 Oct. /Nov. U.S. AM Stations by Call Letters 84 World -Wide Shortwave Stations 96 Emergency Radio Services- Philadelphia Area 99 Dec. /Jan. (1970) U.S. FM Stations by Call Letters Canadian AM Stations by Call Letters Canadian FM Stations by Call Letters World -Wide Shortwave Stations Emergency Radio Services- Washington- Baltimore Area If you save six consecutive issues of Radio-TV Experimenter and Science and Electronics, you will have a complete White's Radio Log. If you have missed an issue, you may be able to get a copy by wish and enclosing $1.00 for each issue. 1. writing directly to the publisher stating which issue you

OCTOBER- NOVEMBER, 1969 83 ¡WEiITE'9 U. S. AM Stations by Call Letters

LnSL3,O Call Location kHz Call Location kHz Call Location kHz

I(AVR Apple Valley, Calif. 960 I(BTC Houston, Mo. 250 KCRL Reno, I(AWA Waco -Marlin. Nev. 780 Tex. 010 ICBTM Jonesboro, Ark. 230 (CRM Crane, Tex. 1580 ao@ I(AWL York, Neb. 370 KBTN Neosho. Mo. 420 I(AWT Douglas, (CRS Midland, Tex. 550 Ariz. 450 KBTO El Dorado. Kans. 360 (CRT Trinidad. Colo. 1240 KA W W Heber Springs. Ark. 370 I(BTR Denver, Colo. 710 KCRV Carutheraville, Mo. 1370 KAYC Beaumont, Tex. 450 KBUB Sparks, Nev. Call Location kHz ICAYE 270 (CSI Pueblo, Colo. 590 Puyallup. Wash. 450 KBUC San Antonio, Tex. 310 KCSR Chadron, Nebr. KAYG Lakewood, Wash. 480 610 (BUD Athens. Tex. 410 Iowa 990 (BUH Brigham City. KAAY Little Rock, Ark. 090 KAYO Utah 800 Idaho 970 (BUS Mexia, KABI Abilene. (Cans. 560 Tex. 590 KCTX Childress. Tex. 510 RAZA Gilroy, Cal. 290 (BUY Ft. Worth, Tex. 540 KABL Oakland, Calif. 960 I(BAB Indianola, Iowa 490 (CUB Tucson. Ariz. 290 (BUZ Mesa, Ariz. 310 Red ICABQ Albuquerque, N.M. 350 IShamrock, Tex. 580 (DAC KACY Port Hueneme, Calif. 520 (BBA Benton. Ark. Ft. Bragg, Calif. 230 690 KBYR Anchorage. Alaska 270 (DAIL Carrington, KADA Ada, Okla. 230 (BBB Borger, Tex. 600 N.D. 600 Pine 270 KBZB Odessa, Tex. 920 (DAL Duluth, KADL Bluff, Ark. (BBC Centerville, Utah 600 KBZY Minn. 610 KADO Marshall, Tex. 410 Salem, Oreg. 490 (DAV Lubbock, Tex. 580 (BBO Yakima, Wash. 390 KBZZ LaJunta, Colo. 400 I(AFE Sante Fe, N.M. 810

84 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER Call Location kHz Call Location kHz Call Location kHz Call Location kHz 1510 KELD El Dorado, Ark. 1400 KFRA Franklin, La. 1990 KGVO Missoula. Mont. 1290 K RV Fresno, Cal. KELI Tulsa, Okla. 1430 KFRB Fairbanks, Alaska 900 I(GVW Belgrade, Mont. 630 KIRX I(irksville, Mo. 1450 KELK Elko. Nev. 1240 I(FRC San Francisco, Calif. 610 1Oklahoma City, Okla. 800 KEVT Tucson, Ariz. 690 KGB San Diego. Calif. 560 KHOG Fayetteville, Ark. 1440 KJET Beaumont. Tex. 1380 KEWE Ft. Collins. Colo. 600 KGBC Galveston. Tex. 540 KHOS Tucson, Ariz. KJFJ Webster City, Iowa 1570 KEW! Topeka, Kans. 1440 KGBS Los Angeles, Calif. 020 I(HOT Madera, Calif. I94Ó KJIM Ft. Worth. Tex. 870 KEWQ Paradise, Cal. 930 KGBT Harlingen, Tex. 530 (HOW Denver, Colo. 630 KJIN Houma, La. 1490 KEX Portland, Oreg. 1190 KGBX Springfield, Mo. 260 (HOZ Harrison, Ark. 900 KJ LT North Platte. Nebr. 970 KEXO Grand June., Colo. 1230 KGCA Rugby. N.D. 450 KHQ Spokane. Wash. 590 KJNO Juneau. Alaska 630 K EXS Excelsior Springs, Mo. 1090 KGCL East Prairie, Mo. 080 KHRB Lockhart, Tex. 1060 KJNP North Pole, Alaska 1170 KEYD Oakes. N.Dak. 1220 KGCX Sidney, Mont. 480 KHRT Minot. N. D. 1320 (JOE Shreveport, La. 1480 KEYE Perryton, Tex. 1400 KGDN Edmonds, Wash. 690 KHS1 Hemet. Calif. 1320 KJOY Stockton. Calif. 1280 KEY.' Jamestown, N.Dak. 1400 KGEE Bakersfield, Calif. 290 IHugo, Okla. 340 KKUA Honolulu, Hawaii 690 KFOR Grand Coulee, Wash. 1360 KGLM Avalon. Calif. 740 KIHR Hood River. Oreg. 940 KKUB Brownfield, Tex. 1300 KFEL Pueblo. Colo. 970 KGLN Glenwood Sprgs.. Colo. 980 K1JV Huron, S.Dak. 340 K LAC Los Angeles. Calif. 570 KFEQ St. Joseph, Mo. 680 16G LO Mason City. Iowa 1300 KIKI Honolulu. Hawaii 830 I(LAD Klamath Falls. Oreg. 960 KFFA Helena, Ark. 360 KGLU Safford, Ariz. 1400 I(IKI< Pasadena, Tex. 650 l

OCTOBER- NOVEMBER, 1969 85 TE Call Location kHz Call Location kHz Call Location kHz I(MYC Marysville, Calif. 410 KOOK Billings, Mont. 970 KRAD E. Grand Forks, Minn. 590 KMYO Little Rock, Ark. 050 KOOL Phoenix, Ariz. 960 (RAE Cheyenne, Wyo. 480 KNAB Burlington. Colo. 140 1(000 Omaha, Nebr. 1420 K RAF Reedsport, Ore. 470 KNAF Fredericksburg, Tez. 910 I

86 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER k Hz Call Location kHz Call Location kHz Call Location kHz Call Location Willmar. Minn. 1340 KTIM San Rafael, Calif. 1510 I(VCI< Wolf Point. Nebr. 1450 I(WLM I(SEK Pittsburg. Kans. 3401 La. 1270 I(WMC Del Rio. Tex. 1490 Tax. 950 KTIP Porterville, Calif. 1450 KVCL Winnfield, I(SEL Lubbock, Redding. Calif. 60 0 KW MT Ft. Dodge, Iowa 540 I(SEM Moses Lake, Wash. 470 KTIS Minneapolis, Minn. 900 KVCV 1400 1240 Sioux City. Iowa 1090 I(WNA Winnemucca, Neo. KSEN Shelby, Mont. 150 KTIX Pendleton, Ore. KVDB 1230 KVEC San Luis Obispo. Calif. 9211 I(WNO Winona. Minn. KSEO Durant, Okla. 750 I(TI(N I(etchikan, Alaska 930 1290 1310 KVEE Conway, Ark. 1330 1(W N S Pratt, Kans. KSET El Paso. Tex. 340 KTKR Taft. Calif. KW NT Davenport, Iowa 1580 400 1(TKT Tucson, Ariz. 990 KVEG Las Vegas, Nev. 97(1 I(SEW Sitka, Alaska Utah 920 I(WOA Worthington, Minn. 730 KSEY Seymour. Tex. 230 KTLD Tullulah, La. 1360 KVEL Vernal, 1280 Ventura. Calif, 4511 I(WOC Poplar Bluff. Mo. 930 KSFA Nacogdoches. Tex. 8110 KTLN Denver, Colo. KVEN 320 1240 Austin, Tex. 300 KWOE Clinton. Okla. KSFE Needles, Calif. 340 l(TLO Mountain Home. Ark. (VET 400 1350 (VFC Cortez, Colo. 740 KWON Bartlesville, Okla. I Maine 910 WARI Abbeville, Ala. 480 WBZE Wheeling, W. Va. 470 WABI Adrian. Mich. 490 WBEX Chillicothe, Ohio 490 WBZY WAR IC Hagerstown, Md. 490 WBFD Bedford, New Castle, Pa. 140 WABK Gardiner, Me. 1280 WARM Scranton, Pa. 310 WCAB Rutherfordton, WABL Amite. Pa. 590 WBFJ Woodbury, Tenn. N.C. 590 La. 570 WARN Ft. Pierce, Fla. 330 540 WCAI Fort Myers, Fla. 350 WABO Waynesboro, WBFN Quitman, Miss. 500 Miss. 990 WARD Canonsburg, Pa, 640 WBGC WCAL Northfield, Minn. 770 WABQ Cleveland, Ohio 540 WART Moulton. Ala. Chipley, Fla. 240 WCAM Camden, N.J. WABR Winter 530 WBGN Bowling Green, Ky. 310 Park, Fla. 440 WARU Peru, Ind, 340 WCAO Baltimore, Md 600 WABT Tuskegee, Ala. 600 WBGS Slidell, La. 560 WCAP 580 WARY Warwick - WBHB Lowell, Mass, 980 WABV Abbeville, S.C. 590 E. Greenwich, Fitzgerald, Ga. 240 WCAR Detroit, WARY R.I. 590 WBHC Hampton, Mich. 1130 Albany. N.Y. 400 WASA Havre de Grace, S.C. 270 WCAS Cambridge, Mass, WABZ Albemarle, N.C. Md 330 WBHF Cartersville, Ga. 450 WCAT 740 010 WASC Spartanburg, S.C. 530 WBHM Birmingham, Orange, Mass- 1390 WACA Camden. S.C. 590 WASK Lafayette, Ala. 550 WCAU Philadelphia, WACB Kittanning, Ind. 450 WBHN Bryson City, Pa. 1210 Pa. 380 WASP Brownsville, Pa. N. C. 590 WCAW Charleston, W.Va. 680 WACE Chicopee. 130 WBHP Huntsville, Ala. 230 Mass. 730 WATA Boone, N.C. 450 WBHT WGAY Cayce, S.C. 620 WAG' The Dalles, Ore. 300 Brownsville, Tenn. 520 WCAI WATC Gaylord, Mich. 900 WBIA Augusta, Carthage, Ill. 990 WACI( Newark, N.Y. 420 WATE Knoxville, Ga. 230 WCBA Corning, N.Y. WACL Waycross, Tenn. 620 WBIB Centreville. Ala. 1350 Ga. 570 WATH Amens, Ohio 110 WCBG Chambersburg, Pa. 1590 WACO Waco, fex. 970 WBI E Marietta, Ga. 000 460 WATI Indianapolis, Ind. 810 WCBI Columbus, Miss, 550 W AC Columbus, M iss. WBIG Greensboro, N.C. 470 050 WATT( Antipo. Wis. 900 WCBK Martinsville, Ind- 1540 W ACT 1 uncalmi,a, Ala. WBIP Booneville, Miss. 400 420 WA I M Atmore, Ala. 590 WCBL Benton, Ky. 1290 WACX Austell. Ga. WHIR Knoxville, Tenn. 240 WCBM 600 WATN Watertown. N.Y. 240 WBIS Bristol, Baltimore, Md. 680 WACY Kissimmee, Fla- 220 WATO Oak Conn. 440 WCBS New York. N.Y. WADA Shelby. Ridge, Tenn. 290 WBIW Bedford, Ind. 880 N.G. 300 WATP Marion, S.C. 340 WCBT Roanoke Rapids, N.C. 1230 WADE Wadesbaro, N.C. 490 WBIX Jacksonville Beach, 210 WAT R Waterbury, Conn. 320 Fla. WCBY Cheboygan, Mich, 1240 WADI( Newport, R.I. 540 WATS 010 WCCC Hartford, WADM Sayre, Pa, 960 WBIZ Eau Claire, Conn. 1290 Decaiiir, Ind. 540 WATT Cadillac, Wis. 400 WCCF Punta Garda, Fla. 1580 WAD() New Mich. 240 WBJM Leminon, S. D. York, N.Y. 280 WATV Birmingham, Ala. 400 WCCM Lawrence, Mass- 800 WAUR Remsen, 900 WBICC Chardon, O. 560 N. Y. 480 WATW Ashland, Wis. 400 WCCN Neillsville, Wis. 1370 WADS Ansonia. Conn. WBKH Hattiesburg, Miss. 950 WCCO 690 WATZ Alpena, Mich. 450 WBICN Newton, Minneapolis -St. Paul, WAEB Allentown. Pa. 790 WAUB Auburn, Miss. 410 Minn. WAEL N.Y. 590 WBKV West Bend- Wis. 830 Mayaguez, P.Rieo 600 WAUC Wauchula, Fla. 470 WCCR Urbana, Ill. 1580 WAEW Crossville, 310 WBLA Elizabethtown, N.C. 440 Tenn. 1330 WAUD Auburn, Ala. 290 WCCW Traverse City, Mich- 1910 WAFC Staunton. Va. WBLC Lenoir City, Tenn. 360 900 WAUG Augusta, Ga. 050 WBLE Batesville, WCDJ Edenton, N.C. 1260 WAFI Middlesboro, Ky. 1560 WAUK Waukesha, Wis. Miss. 290 WCDL Carbondale, Pa, 1440 WAFT Grand 510 WBLF Bellefonte, Pa, 330 Rapids, Mich. 1480 WAVA Arlington, Va. 780 WCDQ Hamden, Conn. 1220 WAGC Centre, Ala. WBLG Lexington, Ky. 300 1550 WAVC Warner Robins, Ga. 350 WBL1 WCDS Glasgow, Ky, 1440 WAGE Leesburg, Va. Dalton, Ga. 230 WCDT 1290 WAVE Louisville. Ky, 970 WBLO Evergreen, Ala. Winchester, Tenn- 1340 WAGF Dothan, Ala. 1320 WAVI Dayton. Ohio 470 WCEC Rocky Mount, N.C. 810 WAGG Franklin, 210 WBLR Batesburg, S.C. 430 WCED Tenn. 950 WAVL Apollo, Pa, 910 WBLT DuBois. Pa, 1420 WAGL Lancaster, S. Bedford, Va. 350 WCEF C. 1560 WAVN Stillwater, Minn. 220 WBLU Salem, Parkersburg, W.Va, 1050 WAG'S' Presque Isle, Maine 950 WAVO Avondale Va. 480 WCEH Hawkinsville, WAGN Estates, Ga. 420 WBLY Springfield, Ohio Ga. 610 Menominee- Mich. 1340 WAVP Avon Park, Fla. 600 WCEM Cambridge, Md. 1240 WAGO Oshkosh, Wis- 390 WBMA Beaufort, N.C. 400 WCEN 690 WAVU Albertville, Ala. 630 WBMC McMinnville, Mt. Pleasant, Mieh, 1150 WAGR Lumberton, N.C. 580 WAVZ New Tenn. 960 WCER Charlotte, Mich. Haven, Conn. 300 WBMD Baltimore, Md. 1990 WAGS Bishopville, S.C. 380 WAWA West Allis, Wis, 750 WCFL Chicago. Ill. 1000 WAGM Forest 590 WBME Belfast, Me, 230 City, N.C. 320 WAWK Kendallville, Ind. 140 WCFR Springfield, Vt, 1480 WART Annville- Cleona, WBM1 San Juan, P. R. l90 WCFV Pa. 510 WAWZ Zarephath, N.J. 380 WBMK West Point, Clifton Forge, Va, 1230 WAI K Galesburg, III. 590 WAXE Vero Ga. 310 WCGA Calhoun, Ga. WAIL Beach, Fla. 370 WBML Macon, Ga. 900 Baton Rouge, La. 260 WAXK Superior, Wis. 240 WCGB Pastillo, P. R. 1050 WAIM Anderson, 320 WBMS Black Mountain, N,C. 350 S.C. 230 WAXU Georgetown, Ky, 580 WCGC Belmont, N.C. 1270 WAIN Columbia, Ky- WBNB Charlotte Amalie, WCGO Chicago 270 WAXX Chippewa Falls, Wis. 150 Virgin Fights., Iii. 1600 WAIR Winston -Salem, N.C. 340 Islands 000 WCGR Canandaigua, WAY B Waynesboro, Va. 490 WBNC Conway, N.Y, 1550 WA IT Chicago, III. 820 WAYD N.H. 050 WCHA Chambersburg, Ozark, Ala. 190 WBNL Boonville, Ind, Pa. 800 WAJF Decatur, Ala. 490 WAY E Baltimore, Md, 540 WCHB Inkster- Mich. 1440 WAJR Morgantown, W.Va. 800 WBNO Bryan, Ohio 520 WCH 440 WAY N Rockingham, N.C. 900 WBNR E Westchester, Pa. 1520 WAKE Valparaiso, Ind. WAYR Beacon, N.Y. 260 WCHI Chillicothe, 500 Orange Park, Fla. 550 WBNS Columbus, Ohio Ohio 1350 WAKI McMinnville, Tenn. WAYS Charlotte, N.C. 460 WCHI Brookhaven, Miss. 1470 WAKN 610 WBNT Oneida, Tenn. 310 Aiken. S.C. 990 WAYX Waycross, Ga. WCH K Canton, Ga, 1290 WA KO Lawrenceville, 1230 WBNX New York, N.Y. 380 III. 910 WAYZ Waynesboro, Pa, 1380 WCH L Chapel Hill, N.C. 1960 WA KR Akron. Ohio WBOB Galax, Va. 360 WCHN Norwich, 1590 WAZA Bainbridge, Du. 1360 WBOC Salisbury, N.Y. 970 WAKS Fuquay- Varina, N.C. 1460 WAZE Clearwater, Md. 960 WCHO Washington Court Fla, 660 WBOK New Orleans, La, WAKX Superior, Wisc. 1320 WAZF Yazoo City, 230 House, Ohio 1250 WAKY Louisville, Miss- 1230 WBOL Bolivar, Tenn. 500 WCHS Ky. 790 WAZL Hazeltun, Pa. 1490 WBOM Jacksonville, Charleston, W.Va. 580 WALD Walterboro, S.C. 1060 WAZS Summerville, Fla. 970 WCHV Charlottesville, Va, 1260 WALE S. C. 980 WBOO Baraboo, Wis. 740 Fall River, Mass- 1400 WC I K Gordon, Ga. WAZY Lafayette, Ind- 1410 WBOP Pensacola, 1560 WALG Albany, Ga. 1590 Fla. 980 WCIL Carbondale, III. 1020 WBAA West Lafayette, Ind, 920 WBOW Terre Haute, Ind- 1230 WCIN Cincinnati, Ohlo 1480 90 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER Call Location kHz Call Location kHz Call Location kHz C all Location kHz 560 W EYY Talladega. Ala. 1580 WDA D Indiana. Pa. 1450 WERG Duluth. Minn. WCIR Beckley. W. Va. 1060 Ala. 1240 WEZE Boston. Mass. 1260 1460 WDA E Tampa. Fla. 1250 WEB1 Brewton, Ky. 1440 WCIS Moss Point, Miss. Owego. N.Y. 1930 WEZJ Williamsburg, WCIT Lima. Ohio 940 WDA F Kansas City. Mo. 610 WEBO WEZQ Winfield. Ala. 1300 WD AK Columbus, Ga. 540 WEBQ Harrisburg, Ill. 1240 WCJU Columbia. Miss. 1450 Buffalo. N.Y. 970 WEZY Cocoa, Fla. Dunn. N.C. 780 WDA L Meridian. Miss. 330 WEBR Tex. 570 WCKB 490 WEBS Calhoun. Ga. 1 110 WFAA Dallas, WCKD Ishpeming. Mich. 970 WD AN Danville, Ill. A. 820 WD AR Darlington. S.C. 350 WEBY Milton. Fla. 1330 WCKI Greer. S.C. 300 1050 WFAB Miami, Fla. 990 WD AS Philadelphia. Pa. 480 WECL Eau Claire, Wis. 1490 WCKL Catskill. N.Y. 560 Carthage. Miss. 1480 WFAD Middlebury, Vt. WCKM Winnsboro, S.C. 250 WD AT Ormond Beach, Fla. 380 WECP WFAG Farmville, N.C. 1250 WD AX McRae, Ga. 410 WEDC Chicago. III. 1240 WCKY Cincinnati. Ohio 530 Pa. 810 WFAH Alliance. Ohio 1310 470 WDAY Fargo. N. Dak. 970 WEDO McKeesport, 1230 WCLA Claxton, Ga. Pines. N.C. 9011 WFAI Fayetteville, N.C. 220 WDBC Escanaba. Mich. 680 W EEB Southern 1470 WCLB Camilla, Ga. WEED Rocky Mount. N.C. 1390 WFAR Farrell. Pa. WCLC Jamestown, Tenn. 260 WDBF Delray Beach. Fla. 1420 WFAS White Plains. N.Y. 1230 WOBJ Roanoke. Va. 960 WEEE Rensselaer, N.Y. 1300 WCLD Cleveland, Miss. 490 WEEF Highland Park, III- 1430 WFAU Augusta. Me. 1340 Cleveland, Tenn. 570 WDBL Springfield. Tenn. 1590 WFAW Ft. Atkinson, Wis, 940 WCLE N.C. 550 WEEI Boston. Mass. 590 WCLG Morgantown. W.Va. 300 WDBM Statesville, 1910 WFAX Falls Church. Va. 1220 450 WDBO Orlando, Fla. 580 WEEL Fairfax, Va. 1460 WCLI Corning, N.Y. Tenn. 1460 WFBA San Sebastian. P.R. 230 WDBQ Dubuque, Iowa 490 WEEN Lafayette, 1330 WCLO Janesville. Wis. WEEP Pittsburgh, Pa. 1080 WFBC Greenville. S.C. Crystal Lake, Ill. 850 WDCF Dade City, Fla. 350 Fernandina Beach, WCLR 220 WEER Warrenton. Va. 1250 WFBF WCLS Columbus, Ga. 580 W DCJ Arlington, Fla. Fla. 1 570 WDCR Hanover, N.H. 340 WEET Richmond, Va. 1320 WCLT Newark, Ohio 430 Pa. 050 WFBG Altoona. Pa. 1290 320 W DDT Greenville, Miss. 900 WEEU Reading. 1390 WCLU Covington. KY. 420 N.C. 1320 WFBL Syracuse, N.Y. 140 WDDY Gloucester, Va. WEEW Washington, 12110 Mansfield, O. 1253900 W FBM Indianapolis. Ind. WCLW WDEA Ellsworth. Me. 370 WEEX Easton. Pa. WCMA Corinth. Miss. 230 Pa, WFBR Baltimore. Md. 1300 460 WDEB Jamestown. Tenn. 500 WEEZ Chester, C. 1450 WCMB Harrisburg. Pa. 290 WEGO Concord, N.C. 1410 WFBS Spring Lake. N. 230 WDEC Americus, Ga. La. 1 110 WCMC Wildwood, N.J. 370 Presque Isle, Maine 1390 W FCG Franklinton. 900 WDEF Chattanooga, Tenn. WEGP Salem. N. C. 1550 WCME Brunswick. Maine 800 WEHH Elmira Heights - WFCM Winston- Ashland. KY. 340 WDEH Sweetwater, Tenn. 1590 WFDF Flint. Mich. 910 WCMI Del. 150 Horseheads. N.Y. WCMN Arecibo. P.R. 280 WDEL Wilmington, Conn. 1480 W FDR Manchester. Ga. 1370 WDEN Macon, Ga. 500 WEHW Windsor. 1370 WCMP Pine City, Minn. 350 Charleston. III. 1270 WFEA Manchester. N.H. 270 WDEV Waterbury, Vt. 550 WEIC Ala. 1340 WCMR Elkhart, Ind, 570 WEI F Moundsville, W. Va. 1370 WFEB Sylacauga. Va. 050 WDEW Westfield, Mass. W F EC Harrisburg. Pa. 1400 WCMS Norfolk. 520 WEIM Fitchburg, Mass. 1280 Martin. Tenn. 410 WOOL Douglasville, Ga. W FF F Columbia. M iss. 1360 WCMT Minneapolis. Minn. 130 WEI R Weirton. W.Va. 1430 WCMY Ottawa, Ill. 430 WDGY Ala. 993 WFFG Marathon. Fla. 1300 WDIA Memphis. Tenn. 070 WEIS Centre. 960 WCNB Connersville. Ind. 580 WEJL Scranton. Pa. 630 WFGL Fitchburg, Mass. N.C. 240 WD IC Cliochco. Va. 430 S.C. 1570 WCNC Elizabeth City. 450 WEKG Jackson, Ky. 810 WFGN Gaffney. Ky. 940 WDIG Dothan. Ala. WFGW Black Mountains, WCND Shelbyville, S.C. 150 WEKR Fayetteville. Tenn. 240 Fla. 230 W DIX Orangeburg, 1 010 WCNH Quincy. N.O. 430 WEKY Richmond, Ky. 340 N.C. WCNL Newport. N. H. 010 WOJS Mt. Oliva. 260 WFHG Bristol, Va. 980 WD12 Bridgeport. Conn. 530 WEKZ Monroe. Wis. WCNR Bloomsburg. Pa. 930 5 30 W EH K Pell City. Ala. 1430 WDKD Kingstree. S. C. 310 WELA Elizabeth. N.J. WCNU Crestview. Fla. 010 Ala. 35 0 WFHR Wis. Rapids, Wis. 1320 WDKN Dickson, Tenn. 260 W ELB Elba. 900 O. 560 I Louisville. Ky. WCNW Fairfield. 270 WELC Welch. W.Va. 50 WFIA Middletown. Conn. 150 WDLA Walton, N.Y. 90 WFIF Milford. Conn. 1500 WCNX Marshfield. Wis. 450 WELD Fisher, W.Va. 6 WCOA Pensacola. Fla. 370 WOLB 5 90 WFIG Sumter. S.C. 1290 WDLC Port Jervis. N.Y. 490 WELE S. Daytona. Fla. WCOC Meridian, Miss. 910 8 10 WFIL Philadelphia. Pa. 560 WDLR Delaware, Ohio 5 50 WELF Tomahawk, Wis. WCOF Immokalee. Fla. 490 9 60 WFIN Findlay. Ohio 1330 WDLM E. Molina, Ill. 9 60 WELT New Haven. Conn. WCOG Greensboro. N.C. 320 Va. 10 WEIS Fountain Inn. S.C. 1600 Panama City, Fla. 59 O WELK Charlottesville, WCOH Newnan. Ga. 400 WDLP 4 10 WFIV Kissimmee. Fla. 1080 WOLT Indianola. Miss. 138 O WELM Elmira. N.Y, WC01 Coatesville. Pa. 420 5 80 WFIW Fairfield. Ill. 1390 W D M E Dover - Foxcraft, Me. 13 40 WELO Tupelo, Miss. WC01< Sparta, N. C. 060 60 WFIX Huntsville, Ala. 1450 230 WDMG Douglas. Ga. 8 60 WELP Easley. S.C. 3 WCOL Columbus, Ohio 3 60 W F IWyoming. WCSM Celina. Charleroi. Pa, 1140 WFSP Kingwood. W. Va. 1560 WCSR Hillsdale. Mich. 1340 WOVH Gainesville. Fla. 980 WESA N.J. 1270 WESB Bradford. Pa. I 490 WFSR Rath. N.V. 1380 WCSS Amsterdam. N.Y, 1490 WDVL Vineland. 660 Caribou. Maine 600 Dawson. Ga. 990 WESC Greenville. S.C. WFST WCST Berkeley Springs. WDWD Mass. 970 WFTC Kinston. N.C. 960 1010 Champaign, III. I 400 WESO Southbridge. W.Va. WDWS Va. 330 W FTG Lnndnn. INew Hampshire Dells, Wis, 990 WSEB Sebring. Fla. 540 WSVS Crewe. WTSN Dover. N.H. 270 W W DA Wisconsin 440 WSWN Belle Glade. Fla. 900 230 WWDC Washington. D.C. 260 WSEL Pontotoc, Mita. 1570 WTSV Claremont, N.H. 080 500 WSWV Pennington Gap, Va. 490 WWDR Murfreesboro. N. C. WSEM Donaldsonville, Ga. WTTB Vero Beach, Fla. 560 N.Y. 050 WSWW Platteville. Wis. 1590 Pa. 550 W W GM Nashville, Tenn, WSEN Baldwinsville, Vt. 1980 WTTC Towanda. Erie. Pa. WSER Elkton. Md. 550 WSYB Rutland. WTTF Tiffin, Ohio 600I WWGO 410 WSYD Mt. Airy. N.C. 1300 530 W W G P Sanford. N.C. 050 WSET Glen Falls. N.Y. 1490 WTTI Dalton. Ga. 430 Tenn. 930 WSYL Sylvania. Ga. Ky. 310 W W GS Tifton. Ga. WSEV Sevierville. 0 WTTL Madisonville. N.Y. 320 Pa. 240 WSYR Syracuse. N.Y. N.J. 9211 WW IJ G Hornell. WSEW Selingsgrove, N.C. 1370 WTTM Trenton, W.Va. 470 Ga. 490 WTAB Tabor City. Wis. 580 WWHY Huntington. WSFB Quitman. Mich. 600 WTTN Watertown. Baltimore, Md. 400 WSFC Somerset. 1(y, 240 WTAC Flint, WTTO Toledo. Ohio 520 WWIN 300 WTAD Quincy. III. 930 Md. 470 WW IS Black River Falls, WSFR Sanford, Fla. Pittsburgh. Pa. 250 WTTR Westminster, Wis. 260 WSFT Thomaston. Ga. 220 WTAE WITS Bloomington. Ind. 370 Mass. 580 430 W W IT Canton. N.0 970 WSFW Seneca Falls, N.Y. 110 WTAG Worcester, WTTT Amherst. Mass. WTAI Eau Gallia. Fla. 560 790 WW) Detroit. M ich. 950 WSGA Savannah, Ga. 400 090 WTUG Tuscaloosa. Ala. 5450 490 WTAK Garden City. Mich. 400 WW1 B Brooksville Fla. WSGB Sutton, W.Va. 450 WTUP Tupelo, Miss. 1270 400 WTAL Tallahassee, Fla. 290 WWDC Superior, Wis. WSGC Elberton. Ga. 340 WTUX Wilmington. Del. 1370 Ala. 610 WTAN Clearwater, Fla. Mich. 590 WWI(E Ocala. Fla. WSGN Birmingham, W.Va. 230 WTVB Coldwater, Bluff. N.C. 1480 WSGO Oswego, N.Y. WTAP Parkersburg. WTVL Waterville. Maine 490 WW KO Fair Ill. 300 W W I(Y I(y. 1380 WSGW Saginaw, Mich. 790 WTAQ LaGrange. WTVN Columbus, Ohio 610 Winchester. 400 WTAR Norfolk. Va. Va. 380 W W L New Orleans. La. 8711 WSHB Raeford N.C. 790 WTVR Richmond, 1170 Ala. 290 WTAW Bryan, Tex. Thomson. Ga. 240 WWLE Cornwall. N.Y. WSHF Sheffield, 240 WTWA 11711 Fremont, Mich. 550 WTAX Springfield. III. WTWB Auburndale. Fla. 570 W W M L Portage, Pa. WSHN 570 N.C. ` WSHO New Orleans. La. 230 WTAY Robinson, III. WTWN St. Johnsbury, Vt. 3411 WWNC Asheville. 480 WTBC Tuscaloosa. Ala. 230 Mass. 490 WWNH Rochester. N.H. 930 WSHP Shippenburg. Pa. 970 WTXL W. Sngfd., 620 490 WTBF Troy. Ala. I 50 WWNR Beckley, W.Va. WSIB Beaufort, S.C. 450 WTYC Rock Hill. S.C. 400 WTRO Cumberland Md. 290 W W NS Statesboro. Ga. 1240 WSIC Statesville, N.C. 590 WTYL Tylertown. Miss. 010 WTBY Waterbury. Conn. WWNY Watertown. N.Y, 740 WSID Baltimore. Md. 50 WTYM East Longmeadow, 1350 Jackson, Va. 790 WTCA Plymouth. Ind. 0 600 WWOD Lynchburg, Vo. WSIG Mount Ala. 9 90 M ass. 1450 WSIP Paintsville. Ky. 490 WTCB Flomaton. WTYN Tryon, N.C. 550 W WO K Charlotte. N.C. 490 WICH Shawano. Wis. 9 60 340 WWOL Buffalo. N.Y. 1120 WSI R Winter Haven, Fla. 30 WTYS Marianna. Fla. 000 140 WTCI Tell City. Ind. 12 Va. 4711 WWOM New Orleans, La. WS1V Pekin. Ill. Mich. 14 00 WTZE Tazewell. R.I. 1740 X Nashville. Tenn. 980 WTCM Traverse City, O. 230 W W O N Woonsocket. WSI Ky. 14 50 WUBE Cincinnati, Ohio 1960 WSJC Magee. Miss. 810 WTCO Campbellsville. WUOO Lewisburg. Pa. 010 WWOW Conneaut. WTCR Ashland. Ky. 14 20 Pa. 1340 W S1 M St. Joseph. Mich. 400 WUFE Baxley, Ga. 260 WW PA Williamsport. 90 1 130 Me. 230 WTCS Fairmont. W.Va. 14 710 WWPF Palatka, Fla. WSJR Modawaska, 20 WUFF Eastman, Ga. 12600 Salem. N.C. 600 WTCW Whitesburg. Ky. 9 080 W W RL New York, N.Y. WSJS Winston- Pa. 8 60 WUFO Amherst, N.Y. 1450 S.C. 510 WTEL Philadelphia. Eufaula. Ala. 240 WWSC Glens Falls. N.Y. WSJW Woodruff, Thomaston, Ga. 15 90 W U LA Fla. 11190 WSKE Everett, Pa. 050 WTGA WULF Alma, Ga. 400 WWSD Monticello. WTGR Myrtle Beach, S. C. 15 20 W W S F Loretto, Pa. 1 Montpelier- Barre. Vt. 240 M U Gainesville, Fla. 390 WSKI Augusta. Ga. 15 50 W U Vt. 1424000 WSKT Knoxville. Tenn. 580 WTHB WUNA Aquadilla. P. R. 340 WWSR St. Albans. 230 WTHD Milford, Del- 9 30 550 WWST Wooster. Ohio 960 WSKY Asheville. N.C. 20 W U N E Baton Rouge. La. N.Y. 400 WTHE Mineola, N.Y. 15 410 WWSW Pittsburgh, Pa. 970 WSLB Ogdensburg, 14 WUNI Mobile, Ala. 1250 1 Terre Haute, Ind. Minn, WSLC Clermont, Fla. 940 WTH WUNN Mason. Mich. 110 WWTC Minneapolis. 090 WTHM Lapeer. Mich. 15 30 320 WWUN Jackson. Miss. 1590 WSLG Donaldsonville. La. 500 WUNO Rio Piedras. P.R. WTHN Thomaston. Ga. 1 W.Va. 1170 WSLI Jackson. Miss. 930 WUNR Brookline. Mass. 600 WWVA Wheeling. Hazleton. Pa. 1 900 Ala. 1360 WSMA Marine City. Mich. 590 WTHT WUOK Cumberland, Md. 270 W W W B Jasper. 1 450 990 Salem, Ind. WTHU Thurmont, Md. 530 W W W F Fayette. Ala. WSLM I 000 WUPR Utado. P.R. Ohio 350 WTIC Hartford. Conn. 340 W W W R Russellville. Ala. 920 WSLR Akron. I 270 W US1 Lockport. N.Y. 1450 610 WTID Newport News, Va. 120 WWXL Manchester, Ky. WSLS Roanoke. Va. 340 WUST Bethesda, Md. 1260 WSLT Ocean City- Somers WTIF Tifton. Ga. 1 Fla. 390 WWYN Erle, Pa. 520 WTIG Massillon, Ohio 990 WUWU Gainsville, WWYO Pineville, W.Va. 970 Pt., N.J. 310 WVAB Virginia Bch., Va. 550 Tenn. 520 WTIK Durham. N.C. 1 560 WXAL Demopolis. Ala. 1400 WSLV Ardmore, I 300 WVAK Paoli, Ind. 1350 Tenn. 6511 WTIL Mayaguez. P.R. 800 WXCL Peoria. Ill. WSM Nashville. I 410 WVAL Sauk Rapids, Minn. 1230 WSMB New Orleans. La. 950 WTIM Taylorville. III. Pa. 430 WXCO Wausau. Wis. W.Va. I 240 WVAM Altoona. 950 WSMD La Plata, Md. 560 WTIP Charleston. S.C. 510 WXGI Richmond. Va. WTIQ Manistique. Mich, I 490 WVAP Burnettown, W.Va. 1490 WSME Sanford, Maine 220 WVAR Richwood, W. Va. 600 WXIT Charleston, Pa. 1 230 Y. WSMG Greeneville. Tenn. 450 WTIV Titusville. N. C. 410 W X I(W Troy, N. New Orleans, La. 690 WVCB Shallotte. Ga. 1230 Litchfield. 111. 540 WTIX Fla. 480 WXLI Dublin, WSMI Point, Ga. I 260 WVCF Windermere, Alaska 980 WSML Graham. N.C. 190 WIJH East Gables, Fla. 080 WXLL Big Delta, 1 390 WVCG Coral 950 N.H. 59U WTJS Jackson. Tenn. 740 WXLW Indianapolis. Incl. WSMN Nashua. I 540 WVCH Chester. Pa. 1460 Tenn. 050 WTKM Hartford. Wis. Va. 490 WXOK Baton Rouge. La. WSMT Sparta, 1 470 WVEC Hampton. 400 WTI

A THANK YOU NOTE FROM THE EDITORS Thank you! The Editors of Donald A. Blesse, Rumson, N.J. A. Pace, Toronto, Ontario SCIENCE AND ELECTRONICS Elmer C. Carlson, Cocoa, Fla. R.L.A. New would like to thank all readers England, Sharon, Mass. who offered information on Charles Ekstrom, Chicago, Ill. station changes, additions, and John Garofano, Framingham, John N. Ramsey, W. Hartford, Conn. deletions during the past few Mass. Jerry months. Though many of the WWR. Garrett, Augusta, Ga. Robertson, Croswell, Mich. letters overlapped, each aided Tom Kneitel, Commack, N.Y. us considerably Gladys Sienkiewicz, Brooklyn, in the task of David making White's Moore, Jr., Little Rock, N.Y. Radio Log as Ark. current as possible at press Mark Wirtz, Evansville, Ind. Lars Nielsen, Dundas, time. If we left your name Ontario Jerry Yacuzzi, W. Hartford, out, please forgive us! Sydney Osgood, Suncock, N.H. Conn.

White's World -Wide Shortwave Stations Many of you who read White's Radio a wide range of prices from most dealers. Log's Shortwave Listings have writ- If you like, send in some of your recep- ten to ask for further information on the tion results to us here at White's, and we'll stations you hear which do not fit into the probably run them. categories of either broadcasting or amateur Propagation Forecast. The noise level stations. They include ships, aircraft, mil - will now start to fall off sharply as cooler tary, police, fire, etc. weather arrives. This means not only im- To DXers, such stations aro generally proved reception (except from south of the classified as utility stations and they consti- Tropic of Capricorn) on the lower SW bands tute a fascinating aspect of the hobby; so like 60 and 90 Meters, but also on the me- interesting in fact, that a great many DXers dium wave BCB-535 to 1605 kHz. No specialize in logging and QSLing them. broadcast DXer should neglect the latter While very few utilities stations have their in his quest for new countries. Here, de- own printed QSL cards, many will gladly pending upon your receiver, patience, and complete and return to you a prepared card luck, you can log such stations as ZNS at for this purpose. Just enclose the card with Nassau, Bahamas (1540 kHz) ZBM 1 Pem- your reception report and ask them to sign broke (1235) and ZFBI St. George's, (960), it and return it-include on the card spaces Bermuda, R. Jamaica (720 and 770 kHz), for the station to fill in their power, antenna R. Barbados and ZBV1 Tortola, British type, and any other data of interest. Virgin Islands (both currently on 780). If you would like to take a whack at this None of these countries have SWBC stations off -beat DX fare, all you have to do is tune and all, with the possible exception of Ber- your communications receiver around to muda, will be best when ionospheric dis- their favorite nesting places. Look between turbances knock out upper latitude QRM. 2 and 3.5 MHz, from 4 to 4.8 MHz, from By the way, and contrary to what some 5.1 to 5.9 MHz, from 6.2 to 7 MHz, from old timers may try to tell you, the noise level 7.3 to 9 MHz, from 10 to 11.5 MHz, from is the only real DX factor (between .3 and 12 to 14 MHz and you'll hear them pouring 30 MHz) that tropospheric weather condi- in from all over the world. For police and tions will affect. fire monitoring, you'll need a special re- Meanwhile it seems that no one knows for ceiver covering the 30 to 50, or 150 to 174 certain what the sunspot count will do next MHz bands -these are readily available at but this may be the last really good winter 96 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER EUROPE, Oct. /Nov. NEAR EAST 1969 ASIA & AFRICA AFRICA LISTENER'S SOUTH LATIN (except (N. of the (S. of the STANDARD IE C AMERICA Sahara) Sahara) TIME Near East)

49, 60e 31,41w 49, 60 0000-0300 (19), 25, (31) 41, 49 49 49, 60 (31) 19w 41, 0300-0600 31, 41, (49) (19w), 19 25, 31 49 0600 -0900 25, 49w 13,16,19 25, 31 19, 25 25 0900-1200 16,19 13,16,19 25, 31 19, 25 (19) 1200 -1500 16,19 13,16,19 31, 49 31w, 49, 60e (19) 1500 -1800 16,19 25, 31, (49) (49), 60 49 25, 31, (60w) 16,19 1800 -2100 16,19 31, (49), 60, 90 49 60 16,19 2100 -2400 16,19 31, hear and log, move your finger down until it finger on the region you want to To use the table out your lift your finger. Underneath your time at which you will be listening and is alongside the local standard The time in the above or bands that will give the best DX results. pointing digit will be the shortwave band compensates for time at the listeners location, which effectively propagation table is given in standard North America. Ab- between the East and West Coasts of differences in propagation characteristics or e follow a band and Eastern North America. When w breviations: w- Western North America e- bands in brackets for that part of the continent. The shortwave listing, it means the band is only good world -wide Shortwave list. Refer to White's Radio Log for our are suggested as possible second choices. 21500 and 21535 kHz. The same midday 13 Meters. This hand is particularly for for also produce improved Latin to a much lesser extent, Afri- period may European and, as compared with last watchers during daylight American prospects can propaganda winter, not because of any signifi- Major African 13 -Meter outlets fall and hours. change in propagation, but due to that (South of the Sahara) are the Voice of cant activity on the international bands. Nigeria on 21455 kHz and Radio RSA on increased Location Location kHz Call Name kHz Call Name Korea R. Pyongyang Pyongyang, N. Fukien, China 4273 - 2200 VNG Lyndhurst, Australia Parintins, Brazil 4500 Ecuador 2360 R. Parintins 4680 HCWEI R. Nacional Espe¡o Quito, R. Lumiere Port au Prince, Haiti 2410 4VU Indonesia 2437 YDG4 RRI. Surakarta, Hangchow, China 2475 to 5060 kHz 2600 Fukien, China 60 -Meter Band -4750 Dzambul, USSR 4760 - Gorovit Dzambul R -TV Congolaise Congo 90 Band -3200 fo 3400 kHz 4765 - Kabul, Afghanistan -Meter 4775 R. Afghanistan - Baku Baku, USSR Lucknow, India 4785 - Gorovit Venezuela 3205 VUD All India R. YVON Ondenas Portenas Pt. La Cruz, Suva, Fi¡i Is. 4790 Ecuador 3230 VRH8 Fi¡i BC 4800 HCSV5 R. Amazonas Cuenca, RRI Ambon, Indonesia Sta Cecilia Lo¡a, Ecuador 3241 YDR3 Domingo, 4810 HCLS3 R. Coro HIMP R. Ocoa Sto. R. Puno Puno, Ecuador 3255 Dom. Rep. 4820 OAX7K Thailand HSKB R. Thailand Bangkok, Dorado Pelileo Ecuador 4830 Bombay India 3265 HCMZ6 V. del Congo 4840 VUB All India R. R. Lubumbashi Lubumbashi, BC Forest Side Mauritius 3285 - Brazil 4850 V3USE Mauritius 3295 ZYM22 R. Cultural Sergipe Sergipe. R. Moscow Moscow, USSR Bhopal, India 4860 - VUD All India R. R. Obispado Peru 3315 ina Grande, 4870 OCX4T 3325 ZYJ2I R. Borborema CB R. Once Sesenta Lima, Peru raz 4880 OCX4E Honduras HRVL R Lux Tegucigalpa, Belem, Brazil 4890 Peru 3335 ZYR59 R. Mara¡oara 4895 OAZ4T R. Chanchamayo Lima, Gabonaise Franceville, Gabon Shanghai, China 3350 R-TV Guatemala 4908 - 3360 TGVN V. Nahuala Solola, R. Amboro La Paz, Bolivia Diambi, Indonesia 4915 CP88 Ecuador 3375 YDK7 RRI 4923 HCRQI R. Quito Quito, BC Ibadan, Nigeria Malanle, Angola 3380 - W. Nigerian 4935 CRSRE R. Club de Malan¡e YDK7 RRI D¡ambi, Indonesia Juan San Juan, Peru 3391 China 4940 OAZ4R R. San R. Peking Peking, R. Madre de Dios Lima, Peru 3450 - Maseru, Lesotho 4950 OAX71 3824 7PA22 7PA22 4960 R. Peking Peking China Petropavlovsk, USSR - Ceylon 4055 Gorovit 4968 R. Ceylon Colombo, - Petropavlovsk - 97 OCTOBER- NOVEMBER, 1969 WHITE'S SHORTWAVE STATION LISTINGS kHz Call Name Location kHz Call Name Location 4980 HIKZ R. Popular Santo Domingo, 9535 CR6RZ Dom. Rep. Emis Official Luanda, Angola 4985 ZYR89 R. Aparaceida 9545 HVJ Vatican R. Vatican Aparaceida, Brazil 9555 City 4995 OAZ4C R. Andina Andina, - V. America Relay Poro, Philippines 5010 Peru 9565 - R. Garoua Garoua, Cameroon - Deutsche Welle Kigali, Rwanda 5020 - R. Ceylon Colombo, Relay 5025 ZYK4I Ceylon 9570 Emis Rural San Francisco - BBC Relay Tebrau, Malaysia 9575 BED9I V. Free Petrolina, Brazil China Taipei, Formosa 5035 Gorovit Alma Ata 9585 - R. Nacional Lisbon, Alma Ata, USSR 9590 Portugal 5041 Emis de Guine Portuguese - R. Peking Peking, China 5055 Guinea 9595 C P87 R. San Rafael La Paz, j - Swiss BC Berne, Switz. 5075 Bolivia 9600 OAX3E R. Peking Peking R. Huaraz Huaraz, Peru 5180 China 9610 OAX8F R. Atlantida Lima, Peru - R. Mauritania Nouakchott, 5535 9618 Muretania R. Peking Peking, OBX7E R. El Sol Lima, Peru 5860 China 9620 CXA6 R. Peking Peking, China SODRE Montevideo, Uruguay 5925 9630 R. Nacional Gorovit Tashkent Tashkent, USSR - Lisbon, Portugal 9640 - BBC London, England 9645 TIFC 49 -Meter Faro del Caribe an Jose, CR Band -5950 to 6200 kHz 9655 - R. Free Europe Munich, 9660 W. Germany BED42 V. Free China Taipei, Formosa 5955 9675 ZYT9 - R -TV Francaise Paris, France R. Diario de Manha Manha, Brazil ZYR226 R. 9685 R. Moscow Gazeta Rio de Janeiro, Brazil - Moscow, USSR 5960 HRHR V. de Occidente Tegucigalpa, 9690 - BBC Relay Limassol, 5970 Honduras 9700 Cyprus - RFE Munich, Germany - R -TV Francaise Paris, France 5975 ZYT44 R. Guara¡a Guara¡a 9710 - RAI Rome, Italy 5980 BED30 Brazil 9720 CR6RZ Emis V. Free China Taipei, lormosa Official g 5985 WNYW R. New York 9725 - V. America Greenville, 5995 New York, NY e, NC - R. Andorra Andorra 9735 - Deutsche Welle Kigali, Rwanda 6000 - R. Moscow Moscow, Relay 6005 CFCW USSR 9745 BEC62 Chinese CFCW Montreal, PQ Air Force Formosa 6010 CE601 R. Norte 9755 PCJ R. Nederland 6020 Santiago, Chile Hilversum, Neth. V. America 9760 - R. Hanoi Hanoi, N. Vietnam 6025 CR6RZ- Greenville, NC 9770 Emis Official Luanda, Angola - BBC London, England 6030 - V. America Greenville, 9912 VUD All India R. Delhi, India 6040 VUD NC 10000 (time All India R. Delhi, India LOL signals) Buenos Aires, Arg. 6055 DYH4 Nat'l 10650 R. Ulan Bator Council Dumaguete City, Phil. - Ulan Bator Mongolia Churches 11515 - R. Peking Peking, China 6060 HCACI 11685 R. V. de Democracia Quito, Ecuador CR6RR Diamang Luanda, Angola 6070 - R. Universite Tananarive, 25 6075 DMQ6 -Meter Band-11700 to 11975 Deutsche Welle Cologne, W. Germany kHz 6078 4VSC V. de St. Marc Port au Prince, Haiti 1700 6080 HRME R. El Patio Tegucigalpa, WIBS Windward Islands 6090 Honduras 1710 V. America - BBC London, England Relay Tangiers, Morocco 6095 HJIW V. del 1720 BBC Relay Centro Bogota, Colombia 1730 Limassol, Cyprus 6105 R. Free Europe V. America Relay Poro, - Munich, W. Germany 1740 ZAA Philippines 6110 - Trans World R. R. Tirana Tirana, Bonaire, Neth. Ant. 1745 Albania 6115 XEUDS R. Univ. HJV Vatican Radio de Sonora Hermosillo, Mex. 1755 Vatican City 6120 DZF4 Call of Orient Manila, R. Hanoi Hanoi, N. Vietnam 6125 Philippines 1760 VUD All HJKE R. Continental Bogota, Colombia India R. Delhi, India 6130 CHNX CHNX 1775 ETLF R. Voice Gospel Halifax, NS 1785 Addis Ababa, Ethiopia 6140 - BBC Deutsche Welle Kigali, Rwanda London, England 790 6145 PRL9 R. Nacional WNYW R. New York Rio de Janeiro, Brazil 1800 New York, NY 6155 0E121 Viennese BC Vienna, Austria Rome, Italy Far East Network 1805 V. America Relay Poro, Tokyo, Japan 1815 VUD Philippines 6165 - Gorovit Kiev All India R. Delhi, India Kiev, USSR 1820 6170 - Army Station R. Peking Peking, China Seoul, S. Korea 1830 6175 - R. Malaysia Kuala Lumpur, V. America Greenville, NC 1845 VU- D All India R. Delhi, Malaysia 1855 India 6185 CSA29 R. Nacional ETLF R. Voice Gospel Lisbon, Portugal 1860 Addis Ababa, Ethiopia 6190 - V. America R. Peking Peking, China Greenville, NC 1870 6200 - R. Sudamericana Lima, Viennese R. Vienna, Austria Peru 1875 DZ- H6 6234 - R. Budapest Budapest, National Council Dumaguete City, Phil. 6330 Hungary Churches - R. Peking Peking, China 6480 R. 1880 LRS R. Splendid - Pyongyang, N. Korea Buenos Aires, Argentina 6644 - R. Pyoingyang 1890 DZE9 Call of Peking, China Orient Manila, Philippines 7060 - R. Peking9 Peking, China ,,,,,,,,,,,,,,,,,,,,w,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, 41 -Meter Band -7100 to 7300 kHz This Issue's Shortwave Contributors 7155 - R. Nationale Tananarive, Malagsay Randy McTavish, Clayton Lake, Me., 7165 Rep. Bill Fred- - R. Free Europe Munich, W. Germany _ ericksman, Philadelphia, Pa., Arnie Wuster, 7180 - R. Liberty Spain Mil- 7190 HLK30 V. = waukee, Wisc., E. K. Herman, Free Korea Seoul, S. Korea Kissimmee, Fla., 7200 - V. America Relay Edward Trumbull, Sr., FPO, San 7230 Wooferton, England Francisco, Cal., - R. Peking Peking, China Willis Rednel, 7260 VUM All India Sayville, N.Y., Steven Thorsen, R. Madras, India San Diego, 7280 - R. Moscow Calif., Gladys Sienkiewicz, New York, 7290 Moscow, USSR - RAI Rome, N.Y., Stan Levine, Galveston, 7295 Italy Tex., Ike Iselin, - R. Liberty Spain Portland, Ore., Arthur 7305 R. Peking J. Chang, Honolulu, Hawaii, - Peking, China Alex MacDonald, 7443 - UN Radio Geneva, Switz. Vancouver, B.C., Sally Esterne, 9009 4X831 Kol Zion Atlanta, Tel Aviv, Israel Ga., Warren Hallowell, Little Rock, Ark., Fred Kleiner, Circleville, Ohio, Dick Williams, Jr., 31 -Meter Band Des -9500 to 9775 kHz Moines, Iowa, H. H. Ustmer II, APO, New York, Morton Yarmy, Dover, Del., Mike O'Dannon, 9500 - R. Peking Peking, China The Village, Okla., L. 9510 - R. Bucharest Bucharest, R. Dolinger, Great Falls, 9515 TAT Rumania Mont., Peter R. Ankara Ankara, Turkey Lelange, St. Agathe, Que., Red 9525 PCJ R. Nederland Hilversum, E. Wilkins, Chattanooga, 9530 Neth. Tenn. - R. Moscow Moscow, USSR 11111101111111111111111111111111 98 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER Name Location Location kHz Call kHz Call Name R. Habana Havana, Cuba Albania 15285 - Australia ZAA R. Tirana Tirana, R. Australia Melbourne, 1905 Delhi, India 15320 - Philippines 1910 VUD All India R. DZF3 Call of Orient Manila, Tirana, Albania 15385 Cologne, W. Germany 1920 ZAA R. Tirana 15435 DMQ15 Deutsche Welle BBC London, England 1925 - Lisbon, Portugal 1935 - R. Nacional kHz BBC ,London, England 16 Band -17700 to 17900 1945 - Angola -Meter 1955 CR6RZ Emis Official Luanda, R. Japan Tokyo, Japan 1965 - VUD All India R. Delhi. India ELWA R. Village Monrovia, Liberia 7715 W. Germany 1975 7765 DMQI7 Deutsche Welle Cologne, R. Liberty Greece kHz 7780 - Ankara, T4rkey I9 -Meter Band -15100 to 15450 7820 TAV R. Ankara VUD All India R. Delhi, India 7850 London, England HCJB V. Andes Quito, Ecuador 7860 BBC 5115 Addis Ababa, Ethiopia - 5130 ETLF R. V. Gospel BBC London, England 5140 Santiago, Chile Band -21450 to 21750 kHz 5150 CE- 1515 R. Corporacion I3 -Meter R. Budapest Budapest, Hungary 5160 Oslo, Norway 5170 LK- V R. Norway R. Prague Prague, Czech. Relay Ascension Island 21450 Lisbon, Portugal 5180 BBC 21495 CSA67 R. Nacional Monrovia. Liberia E. 5195 V. America Relay R. Berlin Berlin, Germany Poro, Philippines 21540 5210 V. America Relay International Spain London, England 5225 R. Liberty 21590 BBC R. Berlin Berlin, E. Germany London, England 5240 21615 BBC International R. Japan Tokyo, Japan India 21640 5250 VUD All India R. Delhi, ,,,,,,,,,,,,,,,,,,,,,,,, ,,,,,,,,,, ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, ,n ,,,,..,,,,,,,,,,,,,,, ,,,,,,,,,, ,,,,,,,,,,,,,,,,,,,,, ,,,,,, , White's Emergency Radio Station Listings for the Philadelphia Area Fire Station Police O SCIENCE AND ELECTRONICS and RADIO -TV Bristol KFF353 EXPERIMENTER furnishes this exclusive listing 155.55 KGF733 46.10 as an aid to our KG 8760 of emergency radio stations 155.55 in the fascinating 155.37 46.10 many readers now engaged Bristol Twp. KGD367 emer- 155.55 KGH408 46.10 and rapidly growing hobby of monitoring 46 10 Briston KGD829 communications. We have and will KGT620 46.42 gency radio Brookhaven 33.70 to different Mawr KGB86I be publishing similar lists devoted Bryn 33 90 metropolitan areas in forthcoming issues so that mobiles 33.42 of KEU993 33 70 be able to accumulate a sizable array Center Point 33.70 you'll Square KGD513 to the index Center KGE263 46 10 this difficult -to- obtain data. Refer Chalfont 155 85 KGE6I5 154.13 1969 program. Cheltenham Twp. 43 on page 83 for our KFA484 154.725 KGB398 154 Chester 46 42 If you desire to obtain similar lists from other Hts. mobiles will Chester KGG324 33,70 in the United States that have not or Collegeville 154 13 areas Colmar KGF244 not be published in this magazine in 1969, then KJD3I3 154 13 Re- KGC902 33 70 we suggest you write to Communications Conshohocken KGD760 33.70 56, Commack, N. Y. 11725. KG E437 46.10 search Bureau, Box Cornwells 46 10 radio serv- Hts. KB0387 They may have a list of emergency Cornwells KGD988 46.10 your locality. Include a stamped, KGE873 46.10 ices that covers KGH700 46.10 with your request. 46.10 self- addressed envelope KBH352 155.55 KGE379 Croydon 46 14

7.1 PHILADELPHIA POLICE DEPT. 154.65 154.71 KEX220 453.35 453.40 453.55 KGF587 453.55 453.75 453.80 453.95 PHILADELPHIA FIRE DEPT.

KG B476 153.95 154.235 170.15 & BORO PENNSYLVANIA MUNICIPAL, I OWN, Fire Station Police 154.13 Twp. KGA260 39.18 Abington KGC774 154.13 KGC984 33.70 Ardmore KEO364 46.42 Aston Twp. KDl1489 33.94 Bally KBQ387 46.10 Bensalem Twp. KAU696 155.37 KGF305 45.62 KGB827 33.90 Berwyn 46.42 don't care what they say, Marvin Bethel Twp. 46.42 "I Boothwyn 46.42 -I'm bored!" Corner KG E909 Booths KGD390 33.94 Boyertown 33.70 Bridgeport Boro KGE756 99 OCTOBER -NOVEMBER, 1969 KFT248 Edqemont GD83I 46.10 Linfield 46.10 Twp. 46.42 KE0362 Elkins Park KGA404 Linwood 33.70 158.85 KGC240 154.13 Lower KGE581 46.42 KGC995 Makefield KFF299 155.37 Exton 154.13 Twp, KGE515 33.90 Lower Merion Fairless Hills KDX425 158.73 Fairview Village 46.10 Twp 33.70 KGC900 33.98 Lower Moreland Fallsington KGD937 39.18 Falls Twp. 46.10 Twp. 37.26 46.10 Lower Feasterville KGE414 155.37 Southamp- * tor' Twp. 155.37 155.55 155.55 Folsom KGC892 46.10 Malvern Fort Washington KFT582 46.42 Marcus Hook KGE327 33.90 Garden City KGC299 33.70 Marshallton KGC873 46.42 Gladwyne KGF8I0 46.42 Media KGG344 33.90 KGB325 158.73 KBK293 Glenside Middletown Twp. KGE363 46.42 KGC476 154.13 45.22 KGD321 33.90 Gradyville KGE979 154.13 Milford Square KGD414 46.10 KDK642 46.42 Morrisville KDG803 46.10 Green Lane Boro mobiles 37.26 Green Ridge KGD336 33.70 KGE827 46.10 Harmonville KF0909 46.42 Morton 39.06 KGF56I 46.10 KGB857 mobiles Hartsville 33.70 Neshaminy KG 46.42 Hatboro KGF437 46.10 Nether Provi- 155.79 Hatfield KGC577 154.13 dente Twp.Tw 39.82 * 46.42 KGF309 Twp. * 154.13 New Hope Havertown 39.90 46.42 Newportille KGF391 46.14 KGB239 39.90 KGC5I2 ' 46.42 Newtown KGH405 46.10 Holmes KG0544 46.42 KGF224 46.10 KEY935 46.42 Norristown Boro KCA484 KEY936 46.42 37.18 KGE336 154.37 KGF7I7 KGF983 Horsham 46.42 Northampton * 33.70 KCV398 154.13 Twp 155.37 46.10 Hulmeville KGF350 154.13 North Hills 155.43 KGD494 46.10 North KGC298 154.13 Huntington Valley mobiles 39.19 Wales Ivyland KGC271 154.13 Nottingham KGC935 33.70 mobiles KGH700 Jamison KDG637 46.10 Oakmont 46.10 155.43 KFA426 46.10 Oaks K88835 46.42 Jeffersonville mobiles 33.70 Ogontz mobiles 33.70 KGE477 33.70 Oreland mobiles 154.13 Jenkintown Boro mobiles 39.16 Kennett KGC640 154.13 Ottsville KG6993 154.13 Square KGE294 mobiles Kennett Twp. 33.90 Paoli 46.10 Kimberton KGE405 33.90 Parkland KGC513 33.90 KHJ665 KGD467 King of Prussia 33.90 Parkside 46.10 Kulpsville KET243 33.70 Penndel KCN702 46.42 KCR921 KGD512 Lacey Park 33.70 Pennsburg 46.10 KCQ242 46.10 Penns Park KGC549 - 33.70 Lafayette Hill KDZ425 155.37 Lahaska KGH34I 33.70 KGD477 46.10 Perkasie 155.43 KDZ403 KGD5B6 La Mott 46.14 Perkiomenville 46.10 Langhorne KGC995 154.13 KFY403 33.70 KG0542 46.10 33.94 Lansdale Boro KGK647 Plumsteadville 154.755 KGE438 154.13 Plymouth Twp. KGD813 46.10 Point Pleasant 370 Pottstown Boro KGE687 46.10 KGF392 11 XIII 11 111 Prospect Park 33.70 ii : u111 W Il KGG370 Quakertown Boro KGE452 46.42 155.13 KGD6I6 46.10 155.37 Radnor Twp.p. KGB330 Hill 45.50 Richboro KCI715 155.37 K Z8I42 46.10 Richlandtown 155.43 KGE378 46.10 Ridley Twp. KDV81 I 46.10 Riegelsville 46.42 Ringing Hill KGE754 46.10 Rockledge mobiles 33.70 Roslyn KGC529 154 13 KGD226 154 07 Royersford 154 13 Schwenkville KGC999 33.70 Sellersville KGD372 33.70 Sharon Hill Boro KGB367 Shinglehouse 45.54 KGD775 46.42 Skippack KFX406 46.10 Solebury KGG930 33.70 Twp. KGF419 155.43 Souderton KFF29I Southampton 33.70 KDZ45I 155,37 KGE802 46.10 155.43 South Media KGD349 Springfield 46.42 KBA863 46.42 Swarthmore Boro KGA378 39.82 Telford KEG833 33.70 Tinicum Twp. mobiles 45.74 Trappe The machine did it by itself!" KBX384 33.70 Tredyffrin Twp. * 45.62 Trevose momm om 1111111111111111 111111111111111111111 KGE42I 111111111111 11111 1111 11 46.10 I. 111.11 MI 11 11111/1111111111111111. 46.14 100 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER r

Fire Station Police Station Police Fire KEA7B8 155.37 KEH660 54.43 KGE452 46.10 Gloucester Twp. 54.385 Trevose Hts. 46.14 s 158.97 * 54.13 KDO246 47.46 Greenwich Twp. 54.385 mobiles 46.10 KDL820 54.43 Trumbauersville 46.10 Groveville Tullytown * 155.55 KGE638 KE LB20 54.43 46.14 * 4. 54.385 KEM672 33.70 Haddon Twp. 156.21 Tylersport 54.43 155.09 KGA346 154.19 54.43 Darby KGA853 KEB467 155.43 KEC380 Upper Haddonfield 54.43 Twp. KEB374 155.37 KDG375 39.28 Haddon Hts. Upper - Boro 54.43 land Twp. Twp. * 37.26 KEE555 KGF463 33.70 Hamilton KEA5I7 54.43 Upper Hamilton Sq. Upper Southamp- 155.37 KDL923 54.43 155.43 Hightstown KDL924 54.43 ton Twp. 33.90 Forge KBB521 KEC839 54.43 KDZ47O 39.82 KEB588 54.13 WallingfordWarminster 46.10 Hopewell Warminster Twp. KDZ470 155.37 KCQ242 KB1956 54.13 155.43 KGD74I 46.10 KEH309 54.13 6.14 Jubustown KEF750 33.74 Warrington Twp. KDA390 155.79 155.37 KEG97I 54.385 KGE910 46.10 Laurel Spgs. Boro KED296 54.43 * 46.10 54.43 Warwick Twp. * 155.43 Twp. 37.26 KGB393 33.70 Lawrence KEF543 54.43 Wayne 33.90 Lawrenceville mobiles 37.26 46.42 Levittown 155.49 mobiles 155.37 45.42 KGD665 33.90 Lindenwold Boro KDY440 West Chester KGA6I2 KED790 155.37 Boro KDA708 55.43 Call mHz Call mHz Magnolia 54.13 33.70 Maple Shade KEB870 155.49 KBT21I West Consho- KGD343 54.43 Twp. 54.13 hocken 33.70 Medford Twp. KJD335 155.49 KBR240 Park KCO285 KDK703 54.13 West KJP390 33.70 KFD660 156.61 KEG600 54.385 KJD3I3 154.13 Merchantville 54.43 West Point * 154.13 Boro Whitehalltehall Twp. KUA762 54.385 Grove KFR636 39.28 54.43 Willow KGC5778 154.13 * Twp. 54.13 mobiles 433.900 Montgomery 54.31 KBR647 54.13 46.14 Twp. KEB309 155.49 Moorestown KEE967 33.74 155.37 Mt. Airy Wrightstown Twp. * Boro KDJ5I2 54.385 155.43 Mt. Ephraim 54.43 46.14 Wycombe KGD959 KDJ5I3 54.385 KGD485 154.13 54.43 Wyndmoor KGI257 46.36 Yeadon Boro KGB242 39.42 KDJ5I4 54.385 43.43 155.49 KAQ261 154.13 MUNICIPAL, TOWNSHIP, BORO Mt. Holly Twp. KEB452 N.J. Mt. Laurel Twp. K D K775 155.49 POLICE & FIRE National Park KCK3I4 158.97 Boro KDA357 154.43 KEG942 156.21 Oaklyn Boro 154.43 Allentown K EH 800 154.43 KF 5973 154.385 KFR678 155.37 KJB229 Palmyra Boro Atco 154.43. KEE554 155.49 46.18 KEB327 158.97 KEJ883 KEB3ó2 155.37 KEE390 Paulsboro Boro Audubon Boro 154.43 3 154.13 Pemberton 154.13 mobiles 154.385 Pennington KED824 KBT8I0 154.43 KEI930 154.13 Barrington Boro KEF872 155.37 155.37 Pennsauken Twp. KEB345 155.61 Belmar Boro 154.43 KEE499 154.13 KEB473 155.37 KCY548 Bellmawr KEV433 154.43 Princeton Univ. KDV709 155.415 KEA4I5 155.49 Riverside Twp. 155.31 Berlinr Boro Rocky Hill KIZ210 KEE94I 155.49 01 KDX508 54.385 ,..,,,,.,,,,,.,.,.,...,.,,,,,,,,,1,,,1,,.,,.,.m,.,,11,,,,1,..,,,....,,.o.,,,,,,,,,,,,,,,,,.,,,,,,..,,.,..,,,.s..1s.,., Blackwood KEI808 54.385 54.43 54.43 Terr. KEG955 Blackwood KFA473 54.13 KJK804 54.31 Blawenburg mobiles 54.13 KCQ270 154.43 Bridgeport 155.49 Burlington Twp. mobiles 153.77 159.03 KEG405 Camden KEB2I0 154.43 154.43 Hill KEA395 155.52 KDO312 Cherry KJH233 154.385 Chews Landing 154.43 55.49 Cinnaminson KEB418 154.13 Clarksboro KAY257 Clementon Boro KEI436 55.37 Collingswood KE8356 56.21 Delanco Twp. KEE393 55.49 Delran Twp. KFG450 55.49 Twp. * 58.97 Deptford 154.13 E. Greenwich Twp. Edgewater Park * 155.49 Twp. 154.43 Ewing Twp. * 37,26 * Gibbstown KED374 158.97 KFR552 154.13 Glendale KDB419 155.37 KDQ337 154.43 "Say, 'Green cheese.'!" 155.37 KEE544 154.385 Glendora . KEG297

101 OCTOBER -NOVEMBER, 1969 WHITE'S PHILADELPHIA EMERGENCY STATIONS Station Police Fire Bondentn. Twp. K DA705 54.22 Bordentown KDN52I /KEY873/KJ Runnemede Burlington R346 54.22 Boro KEC963 155.37 KEF932 154.43 K EG96I Buringtn. Twp. 54.22 KFT567 154.43 01452214522 54.22 Sergeantsville KCU294 Crosswicks KDK771 Sewell 33.74 Delanco 54.22 KF0890 154.13 KDK631 54.22 Somerdale Boro KED959 155.37 Levittown KDB501 Springfield Twp. Lumberton 54.22 154.13 KDK740 54.22 Stockton KDN9I9 Maple Shade KBZ425 Tewksbury Twp. 33.74 Marlton 54.22 33.74 K F 1496 54.265 Thorofare K FT603 Titusville KJ D9I I 54.13 Masonville 54.22 KEB973 54.13 KJJ445 54.22 KG L510 Medford KO K632 Trenton 54.13 Moorestown 54.22 KEB276 37.26 KDG330 54.43 K FO815/ KJJ 446/ KJJ 447 54.22 KGV253 37.26 KEA739 Palmyra KBW792/KDZ359 54.43 Riverside 54.22 KED796 46.38 K D B 499/ K D F 563 / K D X 465 54.22 KEG274 Riverton KDK741 54.43 Willingboro 54.22 KEG513 54.43

KJE I CAMDEN Vincentown 55.16 COUNTY (N.J.) AGENCIES KE92 1 Voorhees Twp. 54.13 Police 155.37 54.43 - Waterford Twp. 155.37 Lakeland KBM9I2 155.37 W. Amwell Twp. 54.385 33.74 Fire- Westmont KEB484 156.21 KEE719 Lakeland 54.385 K B K523 154.265 154.385 154.43 54.43 154.43 Westville Boro KEE405 155.37 KED463 White Horse 54.43 KEM667 154 43 KEE593 54.43 Runnemede KEM666 154.385 Willingboro Twp. KEI693 155.49 154.43 Woodbury KFT567 154.43 KEA936 158.97 KAQ657 54.13 KEJ87I 158.97 Woodbury Hts. KEG635 GLOUCESTER Yardville 154.13 COUNTY (N.J.) AGENCIES KO L82I 154.43 KAV708 KD L822 154.43 Woodbury (fire) 154 13 154.265 KBC661 Woodbury (police) 158.97

PENNSYLVANIA DELAWARE RIVER PORT COMMISSION P.D. STATE POLICE KEA651 KDN502 Philadelphia Camden, N.J. 158.79 42.62 KEF977 KFM497 Trevose Camden, N.J. 154.89 42.62 KGA518 Philadelphia, Pa. KGA990 Philadelphia 42.62 KGE905 158.79 KGA992 Lionville Philadelphia, Pa. 154.89 42.62 KGA999 Quakertown 42 ,62 KGD352 Spring BUCKS COUNTY (Pa.) AGENCIES City 45,14 KGD369 Media 42.62 KC1570 KG D370 Buckingham Mtn. Doylestown (police) 155.13 155.37 42.62 155.43 Turnpike: 155.67 155.55 155.91 159.21 KGF3I8 Doylestown (fire) 46.14 Main channel NEW JERSEY STATE POLICE CHESTER KEA8I0 COUNTY (Pa.) POLICE/SHERIFF Voorhees Twp. 44.62 44.66 44 94 KIZ567 W. 154.68 154.92 Chester 154.785 KEA814 Hightstown 44.62 44.66 44.94 154.68 155.445 DELAWARE COUNTY (Pa.) AGENCIES KEA8I8 Mantua Twp. 44.62 44.66 44.94 154.68 154.92 KDK667 Media (fire) 46.36 46,42 KEF823 S. Hampton Twp. 44.62 44.66 44.94 KGA905 Media (police) 39.82 154.68 154.92 KEA826 Edgewater Twp. 44.62 44.66 44.94 MONTGOMERY COUNTY (Pa.) POLICE 154.68 155.445 /SHERIFF KEA832 Trenton 44.62 44.66 44.94 KGA243 Eagleville 45.26 45.46 154.68 155.445 KGA243 KEA833 Woodstown Norristown 45.26 45.46 44.62 44.66 44.94 154.68 154.92 KEA834 BURLINGTON N. Hanover Twp. 44.62 44.66 44.94 COUNTY (N.J.) AGENCIES 154.68 155.445 Police - KEC848 Plainsboro 44.62 44.66 44.94 154.68 Marlton KFT545 155.445 155.49 KEC877 Bordentown Twp. 44.62 44.66 44.94 Mt. Holly KEE508 /KFR662 Riverside 155.49 154.68 155.445 KFR660 155.49 KED722 Washington Twp. 44.62 44.66 44.94 Willingboro KFR66I 155.49 154.68 154.92 Fire - KFX347 Hopewell 44.62 44.66 44.94 Beverly KDG405 154.68 155.445 154.22 (N.J. Turnpike: 154.83 155.19)

As the operator of the breadbox -size instru- Positive Feedback ment traces the blueprint or photo, 264 of the latest Texas Instruments integrated circuits Continued from page 10 (ICs) within the unit translate straight and curved movements of the plotting cross hairs In the construction field, calculating the into computerized number codes. The numbers amount of concrete needed to resurface a road are displayed as illuminated digits on the con- becomes as simple as tracing an aerial photo trol console and are transmitted to a computer of the route, eliminating the extensive ground card punch or an incremental tape deck. surveying normally required. "Before the new, low -cost TI integrated cir- 102 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER circuits among the three rows of illuminated numericals on the scaler's front panel. The circuitry computes one axis, then the second, then the third, and repeats -all so quickly that to the human eye, the three rows of numerals seem to be changing simultaneously. "This time -sharing of circuitry gives equipment designers an important new area for cost - saving," he said. In MicroMetric's case, time- sharing cuts many logic circuits by a factor of 17, and failure -prone connections within the system by a factor of three.

Reader Mail Department. This Editor receives considerable mail requesting a source for vintage tubes of the pre -war era. (Naturally, I mean World War II.) Well, Arcturus Electronics Corp. has been lucky enough to acquire over 9800 obsolete tubes of 1925 -1930 vintage. These tubes have been added to their inventory of other hard -to- obtain types, which, on the evi- dence, many of our readers would be interested f in obtaining. Does Arcturus have the vacuum tube you want? There's only one way to find out Converting graphic material like this electronic -write, requesting a listing of available tubes circuit into computer language is as easy as tracing Both appear in their mid -1969 cata- digitizer plus prices. lines with MicroMetric Corporation's new it's yours for the asking. Just drop a the drawing on the log, and system. As the operator traces to Arcturus Electronics Corp., Dept. Texas Instruments integrated postcard plotting table, 264 St., Union City, N.J. 07087. Be the scaler cabinet (left) convert JS, 502 22nd circuits within that you read about h in SCIENCE drawing coordinates into digital language for sure to say storage on computer cards or tapes. MicroMetric's AND ELECTRONICS. a innovative use of recent TI circuits resulted in less than oil sealer which is 25 percent less expensive, 011 Down There! A helicopter- transported as large as a third as heavy and less than a fourth device developed by Sinclair Oil's available. prospecting less- capable scaling equipment formerly Tulsa Research Center has been used successfully in the muskeg areas of the Arctic North methods cuits were available, a comparable digitizer Slope of Canada where conventional have been too expensive, too slow, too are both slow and costly. The device, mounted would Helicopter large and too unreliable for most users," Mr. on a quadrapod, is known as the a spokesman for MicroMetric, said. Dinoseis system. It is used in locating under- Elisher, contain "The scaler we've developed is 25 percent less ground geologic structures which may expensive, less than a third as heavy and a fourth oil or gas. in appearance, the as large as less -capable two- dimension scalers Resembling moon vehicles it. Dinoseis quadrapods are sturdily constructed which preceded from one "In addition, the higher speed of the new TI yet light enough to be transported transistor- transistor logic (TTL) microcircuits shot point to another by helicopter. wider range of possible applications," The Helicopter Dinoseis system is composed open up a energy "For example, interferometer systems of a 24 -inch diameter expandable seismic he said. between the legs for measuring large precision- machined metal generator chamber suspended on the ground. A parts can now count at rates exceeding 300,000 of a quadrapod and resting confined mixture of oxygen and propane is ex- cycles per second. spark, could not count above 50,000 ploded in the chamber by an electrical "Older systems the ground second. But the high -speed TI cir- driving the bottom steel plate against cycles per seismic waves into operate at 5 million cps -well above and imparting high -frequency cuits easily rock formations. the requirement for this application. This high the earth to subsurface and shorter pro- Reflected waves were recorded on analog speed means greater accuracy operations, for interferometer users. seismic equipment in the Canadian duction times recorded on digital "There's a common computer practice called but the same could be Mr. Elisher said. "In most in- seismic gear. 'time sharing'," to serve five ex- several companies sharing a A control module, equipped stances, it means and oxygen which computer whose calculating speed is -so ploder units, carries propane single generators, a compressor to great that ownership of the computer could fuel the seismic alone. provide air used in a recoil system and a gen- not be justified by one company and the MicroMetric erator for power for the control system "Time- sharing as applied to (Turn page) scaler, however, refers to the sharing of certain radios. 103 OCTOBER- NOVEMBER, 1969 Positive Feedback

Continued from previous page

The eight seismic energy generators are fired simultaneously by radio from the recording unit, and may be pulsed each 10 seconds. In the Canadian operations, the helicopter moved eight quadrapods and their Dinoseis ex- ploders, two control modules, recording equipment, and personnel one -half mile from one shot point to another in 17 minutes. "We are extremely gratified by results on these initial operations," F. R. Fisher, head of the Research Center, said. "Mechanical operations were excellent, data quality was compar- A member of the IBM Speech Synthesis able and cost was significantly lower than the Laboratory showing a sound spectrogram of the conventional dynamite and shot -hole phrase "allow young Willie." The spectrogram method. illustrates We are encouraged to believe the Helicopter the three lowest formants of speech, indicated by the dark, Dinoseis seismic exploration system will pro- horizontal bars. The vide the answer addresses for the three formants are stored by a to the logistical and economic computer and problems of conducting used to vary the three formant seismic work in the generators required for speech synthesis. remote areas of the world." The formant generators filter the "Hi There, complex Big Boy! ", said in a sexy voice waveforms obtained from a broadband may mean source. nothing more to an IBM engineer Each consists of an attenuator between than the two punch card that programmed it. It's amplifier -type integrators, plus a feedback all because cir- some IBM engineers developed an cuit. Attenuation, determined by the experimental digital ad- device that helps improve the nat- dress from a computer, is obtained by turning uralness of synthesized human speech. on different transistors which modify amplifier The new device -called a formant generator gain. All frequencies, however, are not attenu- -has application in machine -to -man voice com- ated equally, and the frequencies selected vary munication devices. Computer -based systems with the amount of attenuation. The least- atten- using formant generators could be used to pro- uated frequencies, returned to the input by the vide stock market quotations, telephone infor- feedback circuit, determine the frequency range mation assistance and satellite commands. of the generated formant. The formant generator is a digitally tunable It'll be a long time before the female oper- filter which simulates resonances in the human ator's voice at the other end of a telephone line vocal tracts (formants) during speech. Three is computerized. So dream on, lads, while our of the formant generators, each covering a spe- dreams may still be real. cific frequency range, are used to simulate the three lowest resonances of the human vocal Pure H20. A water purification system utiliz- tract. These devices are also modified and used ing ozone has been developed for the in the same speech mil- synthesizer to simulate nasal lions of homeowners, farmers and small com- (such as "m" and "n ") and fricative (such as mercial businesses who derive their water from "f ", "v" and "sh ") sounds. (Fricative- that's a the 15- million wells in America and other pri- word you don't fool with!) vate sources. Many of these wells contain un- Information on the components of speech is desirable impurities and as time goes by the used to design the controls for the formant gen- situation gets worse. erators. These are initially fluctuating wave- Ozone reportedly oxidizes forms-subsequently from water harm- converted to digital data ful pollutants such as sulphur, bacteria, virus, -which determine the frequencies and ampli- and many other kinds of impurities. It is also tude of the sounds produced. One source of reputed to keep pipes such information and plumbing free of is sound spectrograms. blackening and damaging corrosion, This information, after and it digitizing, is stored eliminates the tastes and odors of sulphur and by a computer. It is then used to vary the fre- other unpleasant quencies substances. Ozonator Corpo- of the three formant generators in ration of Batavia, N. Y., creators complex combinations of the system, to simulate the rapidly also maintains that water purified with ozone shifting formants of human voice. These for - contains no residual taste or odor that is the mants are combined with the output of other case with conventional chlorine or other chemi- speech sound generators and filters- fricative, cal equipment. nasal, hiss and "buzz "-to produce recognizable, Ozone is an activated oxygen "spoken" sounds. molecule, formed when air is charged by electricity. It is 104 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER reports the purifier to as that fresh smell after a Ozonator Corporation familiar in nature and self -regulating. Ozone is unstable, and when be completely automatic lightning storm. to add or replace, no a household water supply it There are no chemicals bubbled through and it is uncondi- with and oxidizes existing im- backwashing is necessary, readily combines Since air and electricity purities. tionally guaranteed. only raw materials, there is a minimum Ozone's purification properties have been are the many of maintenance. The Ozonator unit is compact, known for hundreds of years. Paris and from Germany have used easy to install, and operates inexpensively other cities in France and outlets. municipal water since the early standard household electrical ozone to purify system is fine, if all you the development of the Ozonator This water purification 1900s. Until of water. However, industry system, however, ozone was too need is a glass Corporation be solved with major sea-water to produce for application to house- needs can only expensive plants. hold water purification. purification

modulators, etc.-greatly simplify those mys- terious techniques that all too many'technicians Bookmark shy away from. The author shows how to really to work-even Continued from page 13 get that dusty alignment gear how to use it for troubleshooting purposes. The book starts right out by unscrambling revealing both the usual everyday color TV troubles, as those tough "brightness" problems, into once in a blue cures for dozens of elusive troubles in a num- well as those tough dogs run style sense service bench ber of familiar chassis. Following the same moon. Here are common through for solving all sorts of color TV of treatment, the content progresses approaches horizontal oscil- troubleshooting problems, many of them adapt- horizontal deflection systems, techniques. lators, high -voltage regulator systems (shunt, ed from well -established B&W de- a textbook, On the Color TV feedback, and pulse -controlled), vertical Definitely not chroma IF Service Bench tells how to tackle specific prob- flection systems, video amplifiers, circuits, color killers and lems in a logical, professional way. Moreover, circuits, color sync color demodulators. The the author clearly explains how the operation burst amplifiers, and a number of post- repair of each circuit is affected by specific faulty final chapter describes have to be an engi- techniques which make the difference between components. One doesn't receiver and use the information; simple "patching up" and restoring a neer to understand copy, write boiled down to essentials, including to like -new operation. To get your it's all Books, Blue Ridge -cut facts evolved from numerous case his- directly to the publisher. Tab clear tell him the of Book- tories. The reader will find the step -by-step Summit, Pa. 17214 and alignment instructions -RF, IF, chroma, de- worm sent you.

1.111,w11,11,w111111YMIwIIMwMUMIS

BCC today transmits 556í/z hours of radio Stamp Shack programs each day, the various ones intended for domestic, international and particularly Continued from page 8 mainland China reception. This is possible by the use of ten 50 -KW transmitters. In addition to the stations in Taipeh, BCC operates facilities blue waves emanate to cover the entire area of in ten other Formosan cities to form what is the vignette. These represent stereo FM, a serv- called "The Mandarin Network." ice that was introduced to China on the anniversary occasion. What's Nowt The Space City Cover Society, Box 53545, Houston, Tex. 77052, has been preparing and processing commemorative covers in connection with the liftoff and landing of virtually every NASA Spacecraft. Collectors interested in such souvenir covers may write to M. Allen Banks, the society's director, for details. One of the more useful books which collectors should own is "Identify Your Stamps," China by Ervin J. Felix. It is available from the Whit- 40th Anniversary man Publishing Co., Racine, Wis. 53404, at Postal $2.50. Its 260 -pages are packed with answers to Administration which constantly confound beginners Issue questions 1968 (and some veterans). 105 OCTOBER- NOVEMBER, 1969 New Products Continued from page 17

Ratel 550 AM /FM /Multiplex Receiver and will lock onto a station even in low reception areas. There is a smoked -glass dial and brushed Heathkit GD -28 8 -Track Stereo Tape Player gold face plate. Price is $299.50 and you can write for further specs to Martel Elec- tronics, Heath says it should only take about 6 hours 2339 S. Cotner Ave., Los Angeles, Calif. 90064. to put together. The GD -28 comes with a walnut -grained polyurethane cabinet and necessary connecting cables and operates from 120 Pro Transceiver for Hams volts. Price in kit form is $59.95 from the Here is a brand -new transceiver from Heath Co., Benton Harbor, Gal- Mich. 49022. axy, the GT -550, complete with a line of accessories. The Galaxy GT -550 is a 5 -band SSB Lazy Private Listening unit designed for either mobile or fixed station use by amateur If you're just too tired to get radio operators. Really com- up and cross pact, 111/4 x the room to adjust controls while enjoying 123/a x 6 im, and weighing only your 17 lb., it has 550 watts stereo headset, Allied has a unit for you. SSB power, 360 watts The CW. Price of the GT -550 Allied Stereo Headphone 'Remote Control, is $449.00. The Gal- Model H -879, permits a listener to adjust the volume of one or two headphones from his chair. The unit has an on -off switch for speak-

Galaxy GT -550 Transceiver axy accessories include: the LA amplifier at $495.00, the RF console at $69.00, the remote VFO at $75.00, and Allied Stereo Headphone Remote Control H -879 the speaker console at $19.95. Available optional accessories are: AC ers, two volume power supply, mobile power supply, phone controls and standard 1 /4 -in. patch, CW filter, VOX headphone jacks. The headphones plug into the accessory, calibrator, remote control which mobile mounting bracket, and a floor -board connects with low- priced adapter. cable to the amplifier or receiver. For a brochure with complete specs Size of Al- on the line write lied's H -879 is 23/4 x 4 x 2 in. and the price Galaxy Electronics, 10 S. 34th is St., Council Bluffs, Iowa $9.95. A 25 -ft. roll of cable costs $1.60. In all 51501. Allied stores or by mail from Allied Radio Antennas, Corp., 100 No. Western Ave., Chicago, Ill. to the Rear! 60680. Model TLM is an antenna trunk lip mount which requires neither drilling nor defacing of your vehicle. The clamp and antenna Just Give Us the FAX base support are constructed from 1/4-in. Distributed by Martel Electronics, carborized this is the plated steel and the mount cover is grey Cycolac Rotel 550 AM /FM /Multiplex receiver, which plastic. Easily gets installed in seconds on the rear a rating of 70 watts IHF. The 550 has or side of any automobile front -end tuning, trunk lip, TLM will individual bass and treble give lowest SWR and minimum controls for each channel, noise. The as- loudness control for sembly includes New -Tronics' break -cable boosting extreme highs and adap- lows at moderate tor with all connections factory soldered plus listening level, and a wide power bandwidth. a special coax cable retainer to protect it The tuner is designed for both when AM and FM the trunk lid is closed. Model TLM will accom- 106 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER measure modate a wide selection of antennas with the contact. Thermy will electronically from °F to 400 °F or from 3/s -in. base. No special tools required. temperatures -60 standard with a $8.95 and inquiries should be directed -50 °C to 200 °C, used in conjunction Price is get tem- Dept., New- Tronics Corp., 15800 Com- quality voltmeter or multitester. You to Sales of ordi- merce Park Dr., Brookpark, Ohio 44142. perature data beyond the capabilities nary mercury thermometers because its two 40-in. long leads and its 11/2-in. long steel probe tip permit entry into heretofore inaccessible areas. A sensitive thermal unit inside the probe increases in resistance as it cools, lowers in resistance as it heats. When you use Thermy with a multitester, hold the probe tip against an object for a quick resistance read -out. A conversion scale is provided to translate ohms to F or C degrees. In a protective case, Thermy is priced at $14.95, and for more info write Mura Corp., 355 Great Neck Rd., Great Neck, N.Y. 11021.

New -Tronics TLM Trunk Lip Mount

Take Your Component's Temp? Just a mite bigger than a fountain pen, Thermy is a handy new sensing device that quickly gives accurate temperature readings of any solid or liquid with which it is placed in

"Sorry, the number you have dialed is permanently out of order!"

Mura Corp. Thermy 11 11

not crack the circuit in a reasonable time, Univox Super Fuzz Box we must make an educated guess. First off, there is a clipper such as found in all fuzz - Continued from page 72 boxes. Then there appears to be self- oscil- lation triggered by positive feedback above by the EX- For example, Fig. 1 is EXPANDER off; a predetermined level, as set this is a Fig. 2, about 1/4 EXPAND; Fig. 3, 1 EX- PANDER control. Finally (and triggered by PAND and 'Fig. 4, 3/4 EXPAND. (Full ex- far -out guess), a multivibrator pansion is bearable only by Martians.) The the positive and negative peaks of the basic two -position TONE switch provides either waveform provides the impulses. the basic type of fuzz effects such as rep - The Univox Super -Fuzz is priced at including one connecting cable and k resented in Figs. 1 to 4, or the impulse ef- $24.95, fects as in Figs. 5 to 7. a 9 -V battery. For additional information How It Works. Since the circuit types write Lafayette Radio Electronics Corp., and schematic of the Univox is one of the Dept. S, III Jericho Tpke., Syosset, N.Y. world's best kept secrets, and since we could 11791. 107 OCTOBER- NOVEMBER, 1969 other. Then MWARS moves to 7258 and Ham Traffic ECARS moves to 7253. The practical Continued from page 77 value of this nation -wide emergency setup was first proved when a mobile in Georgia encountered a serious erating privileges, each of us should do a automobile accident and couldn't raise any- share of getting rid of the hooligan ham one in his area to call the police. The West who has become noteworthy enough to be Coast group heard his calls, however, and an mentioned in the FCC's official report. And Arizona station called that state's Highway condemnation on the air won't do it- that's Patrol, which had hot -line communications merely stooping to this alley cat trend which with Georgia authorities. we're trying to wipe out. But total ostra- This story brings up the question: why cism of any ham who doesn't behave himself don't hams have more emergency monitor- on the air can be effective. Make a firm reso- ing frequencies set aside for just such oc- lution to have nothing to do with a fellow currences? Actually, this is an old idea whose behavior on the air is open to ques- which has been tried many times, but it has tion. Once he runs out of people to talk to, only been a success over a wide area since he will mend his ways. these 40 -Meter groups got interested. Instant Emergency Network. Some For many years in the past, the ARRL scoffers say that hams no longer can be designated a frequency in each band, both really effective in providing emergency com- phone and CW, for "National Calling and munications. But an ever -growing group on Emergency Frequencies." For a while, the 40 -Meter phone is proving this just isn't so! League's Official Observer corps was re- These fellows and gals have set up a full - quested to send post cards to casual users time emergency net that spans the U.S. from of these frequencies, notifying them of the coast to coast. And they keep it operating voluntary plan to keep these frequencies every day of the week and almost around clear for emergency calls. the clock! The beauty of the thing is that However, the idea never really caught on. the net is organized so it can be strictly an Everybody agreed it sounded good, but few easy -going -type operation. However, it can operators made the effort to make the idea be instantly switched into a brisk, efficient work. Now, though, with the leadership emergency net when the need arises. and enthusiasm shown by these three re- At a time when idle rag chewing seems gional emergency nets, the idea of full -time to be taking over the low phone bands, these emergency frequencies is gathering momen- operators are showing the world they have tum again. a serious interest in using their ham rigs for Maybe you're interested? If so, listen in work, not just for play. on 7255 kHz for a while to learn how they You've read about the West Coast Ama- operate. They'll be glad to have you join teur Radio Service (WCARS) in this column them. And if you're on a trip with a 40- before. That net has been operating since Meter mobile rig in your car, try monitoring 1963 on 7255 kHz. Its main function has this frequency as you drive along. been to provide the system for mobiles en- countering traffic accidents, fires, or other emergencies to be able to notify the proper authorities through operators who monitor this frequency at home. Western highways carry a lot of traffic, and sometimes help is quite a ways away in the wide open spaces. Result is that this net has helped a lot of people in trouble over the years. Last year, the Mid -Western Amateur Radio Service (MWARS) went into operation to serve the same function in the middle of the country. Now this year the East Coast Amateur Radio Service (ECARS) went into operation. All three nets operate on 7255 kHz except when propagation con- "High voltage was my problem." ditions cause them to interfere with each

108 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER Their Time Is Your Time Continued from page 51

As with most Down Under stations, listeners will find our early morning hours best. Gen- erally, its 10 -kW transmitters on 5.425 and 7.515 MHz are audible after 1200 GMT. Before that, your best bet is 12.005 MHz. Our list shows a broad cross section of some of the standard time stations now on the air. Some are sure bets; others will really try your skill, patience, and -you guessed it-luck. With the time services you can never be sure what will pop up next. Just about everyone has heard the "tock, it is, you're in for a good tock, tack" of WWV -the big U.S. time sta- But whatever fion. Tune 'em in and send a report today. time!

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"Before his (Marconi's) invention . . . Famous. Patents ether borne communication traveled some eighty miles. He lengthened the arc to Continued from page 78 6000. Whether or not this was 'inventive' legally, it was a great and beneficial achievement. Today, forty years after the event, the on for years, finally The court battle dragged Court's decision reduces it to an electrical Court in 1943. Nearly reaching the Supreme mechanic's application of mere skill . . . was granted, the 40 years after the patent "By present (1943) knowledge it would in the land found Marconi's highest court be no more. School boys and mechanics patent claims invalid. now could perform what Marconi did in wise old men of the Supreme But even the 1901. But before then wizards had tried In a split Court couldn't agree completely. and failed." e decison, three of the judges strongly dis- agreed with the majority. Tuning patent are Mr. Justice Rut- Copies of Marconi's Four-Circuit One dissenting judge, available for fifty cents each from the U.S. Patent ledge, attacked the decision of his colleagues Office, Washington, D.C. 20231. In ordering, give with the statement: the number of the patent -No. 763,772.

off. If you try to adjust the converter during Police Convertor a slack part of the day, it may be minutes calls all in- Continued from page 43 or even an hour between -for tents and purposes the band might appear dead. Just because you can't tune in a signal and hunt for the stations-and hope they don't assume the converter isn't working. come on while you're tuning. Sometimes better reception may be obtained on different parts of the FM band; for example, you may get better reception with the radio tuned to 90 MHz than to any other frequency slot in the band. Once you have the vhf band tuned in, experiment with the radio's tuning and R1's adjustment. Using the Converter. Keep in mind that police and fire calls, are not broadcast continuously as are the broadcasts from AM radio stations. These FM transmissions are of short duration and then the carrier goes 109 OCTOBER- NOVEMBER, 1969 on the moon, and they have not been swal- The Skies Above Us lowed by dust. Continued from page 45 * Why don't the youngsters in astronomy wait, before they rush into print, for at least Now, astronomers have discovered tha one second thought -about lunar surface a star close to the center of the Crab Nebula dust, quasars, pulsars, and so on -so they is changing in brightness at the rate of once can sacrifice immediate notoriety in favor in a thirtieth of a second. This star must of possible studiously- studied chance for be the "villain of the piece." This is the immortality? remnant of the star which, about four thou- The history of all sciences points up the sand years ago, "blew its top." necessity of plodding along until no "bugs" Almost everyone today knows that an remain in the theory and its fulfillment. If atom consists of positively- charged particles Isaac Newton could wait more than 20 years (protons) plus an equal number of neg- before announcing his law of gravitation in atively- charged particles (electrons) to make 1686, our modern astronomers can wait a the atom electrically neutral. If the elec- year or two before cluttering trons up our tech- and the protons are smashed together nical journals with fast -judgment pronounce- because of intense gravitational attraction, ments, later to be demolished. they ¡make neutrons. These neutrons will It was Kepler who demolished, once not give off visible light but, around them, for all, the Ptolemaic (earth- centered) compressed hy- into a hard ball, may be a few pothesis of planetary motions, which had normal atoms. been the law from 1500 years earlier. These "neutron stars" may be much heav- There are many mysteries awaiting our ier and denser than our sun or any matter explanation in this universe of ours. Let no we know or can imagine, yet be only 10 one think that, from a few miscellaneous miles or so in diameter. Such an unbeliev- observations, he can arrive at a complete ably dense ball may spin on its axis in a explanation, especially when it blithely over- fraction of a second and, if one side is throws reasonably -established physical laws brighter than any other part, the flickering derived from decades or even a lifetime of of a pulsar may be explained, say the experts. observations, correlations, and conclusions. The crux of * the matter is: have we How incompetent will seem many would -be found in the faint star near the middle of geniuses when their snap -judgment rushings the Crab Nebula an example of these col- into print will be demolished by those who lapsed, exceedingly -condensed, hypothetical come after. neutron stars? There were the "quasars," objects which, like the pulsars, were discovered by radio telescopes. Instantly, some astronomers, especially the younger and young middle - aged ones, had instant explanations for these new -found objects, and their "explanations" fell, one -by -one, by the wayside. After several years, we don't yet know whether the quasars are near -by objects of reasonable radiation or enormously distant objects vio- lating all of our previously- derived laws of nature, including impossibly -high emission of energy and impossibly -fast apparent ve- locities of recession -faster than the velocity of light. Too many young astronomers and physi- cists want to get too quickly into the act. We might compare this with what Dr. Thomas Gold, a few years ago, said about "The die is the surface of the moon -that it was an cast, the book is written, to be read now or by posterity, I ocean of dust, and any man who care not which. stepped It can well await its reader. on it would be drowned Has not God and smothered by waited six thousand years for an observer dust. We have landed ?" many Surveyor probes The words of John Kepler from his last book. 110 SCIENCE AND ELECTRONICS, formerly RADIO -TV EXPERIMENTER c wssFeo C% GC1'iGt lCiCv FOR BIGGER PROFITS! NEW CAREER OPPORTUNITIES! READ AND REPLY TO THESE CLASSIFIED ADS

in the next available issue Classified Ads 65C per word, each insertion, minimum 10 words, payable in advance. To be included 10th. Address orders to C. D. of SCIENCE & ELECTRONICS (formerly RTV -Exp.) copy must be in our New York Office by Sept. Wilson, Manager, Classified Advertising, SCIENCE & ELECTRONICS, 229 Park Avenue South, New York, N. Y. 10003. ADDITIONAL INCOME INVENTIONS WANTED RADIO & TELEVISION MONEY-Sparetime Opportunity Panel- WE either sell your invention or pay THOUSANDS AND THOUSANDS of ists At Home Wanted By New York Re- cash bonus. Write for details. Universal types of electronic parts, tubes, transis- searcher. Leading research firm seeking Inventions, 298 -5 Marion, Ohio 43302. tors, instructions, etc. Send for Free Cat- people to furnish honest opinions by mail alog. Arcturus Electronics Corp., MRT, from home. Pays cash for all opinions MISCELLANEOUS 502 -22nd Street, Union City, N. J. 07087. rendered. Clients' products supplied at no For information write: Research 669, cost. "ADULT" Books, Magazines . Free POLICE-Fire-Aircraft-Marine-Ama- Mineola, N. Y. 11501, Dept. 633 -SE. illustrated catalogue! State age. (Send teur calls on your broadcast radio! Free stamp.) Clifton's, Box 1068 -M9, Saugus, catalog. Salch Company, Woodsboro EEI4, MAKE Your Classified Ad Pay. Get Calif. 91350. Texas 78393. "How To Write a Classified Ad That worth $2.00 Pulls." Includes certificate KNIVES 101 Imported Novelty Knives. RADIO & TV Tubes 330. Free Catalog. toward classified ad. Send $1.25 to C. D. Diego, Wilson, Science and Mechanics, 229 Park Catalogue 506. Friedmar Imports, Box Cornell, 4217 West University, San Avenue South, New York, N. Y. 10003. 533 -EE, Montebello, Calif. 90640. California 92105. OPPORTUNITIES MONEYMAKING OPPORTUNITIES RECEIVING & INDUSTRIAL TUBES, BUSINESS TRANSISTORS, All Brands-Biggest Dis- Technicians, Hobbyists, Experi- by Mailorderl EASY -to -start rubber stamp business counts. I MADE $40,000.00 Year home in spare time. Make up to $16.50 an menters- Request Free Giant Catalog and Helped others make money! Start with free. Write Zalytron, 469 Jericho Turnpike, Box 318 -T, hour without experience. Facts Save! $10.00 -Free Proof! Torrey, to: Roberts, 1512 Jarvis, Room CR- 105 -A, Mineola, N. Y. 11501. Ypsilanti, Michigan 48197. Chicago, Illinois 60626. Police fire radio dispatchers. FREE Book "990 Successful, Little - For- HEAR + Known Businesses." Fascinating! Work COMMERCIAL Chemical Products Catalog of exclusive "confidential" offi- N. Y. mulations. Catalog $1.00 (Refundable). cial police /fire dispatcher stations. Call home! Plymouth 311 -J, Brooklyn, Polychemical, 2411 Northeast 136 Lane, signs! Frequencies! Send stamp. Commu- 11218. Miami, Fla. 33181. nications, Box 56 -RT, Commack, New York 11725. 1000 GOLD STRIPE Name and Address LEARN Secrets That Make You Rich: Labels, 500 SEASONS GRIse.IING LA- $2.00 Book. Guinn, 1)669, 78 Tubmill, Mil- TUBES BELS. 500 PERSONALIZED PHONO- ford, Delaware 19963. GERMAN and JAPANESE - GRAPH Record Labels $1.00 each or three Parts. Send $1.00 for Price List. The for $2.89. SPLENDID GIFTS, 15772 Matthews Company, Box 151, Lawton, NORTHLAWN, Dept. SM -10, DETROIT. PERSONAL Oklahoma 73501. 48238. MICH. DE- SUBMINIATURE LISTENING "DISTANCE Crystal Set Construction" EDUCATION & INSTRUCTION VICES, low priced, high performance - Handbook-500. "Coil Winding" -500. Cat- direct from manufacturer. Dealers Wel- 12041 -H Sheridan, Gar- come. Audiotronix, RT -8, 156 Fifth Ave- alog. Laboratories, SCHOOL of Occult Science, P.O. Box nue, New York, N.Y. 10010. den Grove, Calif. 92640. 13372, New Orleans, La. 70125. ELIMINATE Debts Without Borrowing! SUPER Distance AM Broadcast Recep- ELECTRONIC COMPONENTS Particulars Free. Helper, 10639 Riverside, tion, "Music Magnet" Kit $2.95. Informa- No. Hollywood, Calif. 91602. tion 25d. Rand Laboratories, Winthrop, FREE CATALOG Over 80 different solid Maine 04364. state electronic products. New Electronic STOP Smoking this Book presents Medi- Kit, ppd. See complete line cal and Psychological Method. Refund Strobe $9.95 Laury, 41886 -A Debra, C.B. BUYERS' Guide-A new magazine of Bowman solid state products at your Guarantee $2.00. for the buyers of Citizen's Band Electronic local authorized dealer. Bowman Elec- Elyria, Ohio 44035. Equipment. Send $1.25-includes Postage tronics, Inc., 155 East 1st Avenue, Roselle, to C. B. Buyers' Guide, 229 Park Avenue N. J. 07203. PRINTING, MIMEOGRAPHING & South, New York, New York 10003. MULTIGRAPHING GIFTS THAT PLEASE STAMP COLLECTING 250 EACH -letterheads, statements, en- FREE distinctive gift catalog. Renwell velopes and business cards. Send copy (up Company, 5305 Wellington, Chicago. Ill. to 5 lines) and $17.75 to The Wrightway, FREE 121 Flag Stamps With Approvals. 60641. 404 East Green, Champaign, III. 61820. W -B Stamps, Wilkes -Barre, Penna. 18703.

THERE IS NO CHARGE FOR THE ZIP CODE- PLEASE USE IT IN YOUR CLASSIFIED AD For Greater Classified Profits WHY NOT TRY THE NEW combined classified ad medium Your classified ad will appear in SCIENCE & MECHANICS MAGAZINE as well as in a minimum of four other SCIENCE & MECHANICS PUBLICATIONS. Write now for information to C. D. Wilson, Manager, Classified Advertising, SCIENCE & MECHANICS, 229 Park Avenue South, New York, N. Y. 10003.

OCTOBER -NOVEMBER, 1969 Join "THE TROUBLESHOOTERS" They get paid top salaries for keeping today's electronic world running

Suddenly the whole world is going elecironic! And behind the microwave towers, push-button phones, computers, mobile radio, television equipment, guided missiles, etc., stand THE TROUBLESHOOTERS -the men needed to inspect, install, and service these modern miracles. They enjoy their work, and get well paid for it. Here's how you can join their privileged ranks- without having to quit your job or go to college in order to get the necessary training.

112 "SCIENCE 'AND ELECTRONICS, formerly RADIO-TV EXPERIMENTER getting new lessons in Laser Theory and Application, usT THINK how much in demand you would be if you Microminiaturization, Single Sideband Techniques, Pulse Jcould prevent a TV station from going off the air by Theory and Application, and Boolean Algebra. a transmitter ...keep a whole assembly line repairing In addition, there is complete material on the latest by fixing automated production controls...pre- moving troubleshooting techniques including Tandem System, a bank, an airline, or Y9ur government from making vent Localizing through Bracketing, Equal Likelihood and mistakes by servicing a computer. serious -Split Division, and In- circuit Transistor Checking. whole industries depend on Electronics. When Half Today, are special lessons on servicing two -way mobile or emergencies occur, someone has got to There breakdowns radio equipment, a lucrative field in which many of our take over, and keep things running. That calls move in, students have set up their own businesses. for one of a new breed of technicians -The Trouble- shooters. Your FCC License -or Your Money Back! expensive mistakes or delays, Because they prevent Two -way mobile work and many other types of trouble- a title to match. At Xerox and they get top pay -and shooting call for a Government FCC License, and our called Technical Representatives. At IBM Philco, they're training is designed to get it for you. But even if your Engineers. In radio or TV, they're the they're Customer work doesn't require a license, it's a good idea to get one. Broadcast Engineers. Your FCC License will be accepted anywhere as proof need to break into the ranks of The What do you of good electronics training. You might think you need a college Troubleshooters? And no wonder. The licensing exam is so tough that don't. What you need is know- how -the degree, but you two out of three non -CIE men who take it fail. But our TV service technician has -only lots more. kind a good training is so effective that 9 out of 10 CIE graduates with Think With Your Head, Not Your Hands pass. That's why we can offer this famous warranty confidence: If you complete a license preparation course, of The Troubleshooters, you'll have to be ready As one you get your FCC License -or your money back. to tackle a wide variety of electronic problems. You may not be able to dismantle what you're working on -you Mail Card for 2 Free Books it "in your head." You'll have must be able to take apart Want to know more? Send for our 44 -page catalog de- Electronics to understand the engineer- to know enough scribing our courses and the latest opportunities in Elec- diagrams, and calculate how ing specs, read the wiring tronics. We'll send a special book on how to get a at any given point. the circuits should test Government FCC License. Both are free-just mail the this can be much simpler than you think. Learning all bound -in postpaid card. If card is missing, use coupon it without setting foot in a class - In fact, you can master below. room...and without giving up your job! For over 30 years, the Cleveland Institute of Electron- ENROLL UNDER NEW G.I. BILL at home. We've ics has specialized in teaching Electronics All CIE courses are available under the new G.I. Bill. If developed special techniques that make learning easy, you served on active duty since January 31, 1955, or are for G.I. even if you've had trouble studying before. Our AUTO - in service now, check box on card or coupon PROGRAMMED* lessons build your knowledge as easily Bill information. and solidly as you'd build a brick wall -one brick at a time. And our instruction is personal. Your teacher not Cleveland Institute only grades your work, he analyzes it to make sure you of Electronics are thinking correctly. And he returns it the same day CIE Ohio 44114 received, while everything is fresh in your mind. 1776 East 17th Street. Cleveland, Always Up -To -Date r To keep up with the latest developments, our courses Cleveland Institute of Electronics Street, Cleveland, Ohio 44114 are constantly being revised. This year CIE students are 1776 East 17th Please send me without cost or obligation: 1. Your 44 -page book "How to Succeed in Electronics" describing can the job opportunities in Electronics today, and how your courses WCOLLEGE -LEVEL prepare me for them. FCC License." NE COURSE IN 2. Your book on "How To Get A Commercial in ELECTRONICS I am especially interested o Electronics El Broadcast O First Class ENGINEERING Technology Engineering FCC License for men with prior experience El Electronic o Industrial CI Electronics Electronics Engineering in Electronics. Covers steady - Communications state and transient network theory, solid state physics Name I.IEASF ..iNll and circuitry pulse tech - niques, computer logic and Address mathematics through calcu- 7ip lus. A college -level course for City State men already working in Elec- t Check here for G. I. Bill information. EX-34 I tronics. I J Reg. U.S. BUILD 20 RADIO Pot. Off, CIRCUITS AT HOME only with the New Improved 95 PROGRESSIVE RADIO "EDU -KIT "B A Practical Home Radio Course Now Includes * 12 RECEIVERS * No Knowledge of Radio Necessary * 3 TRANSMITTERS No Additional Parts *SQ. WAVE GENERATOR * or Tools Needed * SIGNAL TRACER * EXCELLENT BACKGROUND FOR TU * AMPLIFIER SCHOOL Training * SIGNAL INJECTOR INQUIRIES INVITED Electronics Technicians Since 1946 * CODE OSCILLATOR * Sold In 79 Countries FREE EXTRAS YOU DON'T HAVE TO SPEND 'SET OF TOOLS HUNDREDS OF DOLLARS FOR A RADIO COURSE The SOLDERING IRON "Etlu -Nit" Offers you an outstanding PRACTICAL HOME rock- bottom price. Our Kit is designed RADIO COURSE at a ELECTRONICS use to train Radio & Electronics Technicians, I TESTER of the most modern methods of home training. You will learn making PLIERS- tion practice and servicing. THIS IS A COM,xLCiE radio theory, construc- CUTTERS You will learn how to build radios, RADIO COURSE IN EVERY DETAIL. VALUABLE DISCOUNT CARD In using regular schematics; how to wire and CERTIFICATE OF MERIT service radios. You with solden TESTER Punched metal chassis as well as latest development)lof Priinted or INSTRUCTION MANUAL You will learn the basic principles of radio. You will Circuit chassis. HIGH FIDELITY GUIDE QUIZZES RF and AF amplifiers and relators, Construct, study and work with TELEVISION BOOK RADIO and practice detectors. rectifiers, test equipment. You TROUBLE code, using the Progressive Code Oscillator. You ill learn SHOOTING BOOK troubleshooting, using the Progressive Signal Tracer, Progressivewill learn and practice MEMBERSHIP IN RADIO TV CLUB: gressive Dynamic Radio & Electronics Signal Injector, Pro- CONSULTATION ing instructional material. Tester, Square Wave Generator and the accompany- SERVICE FCC You AMATEUR LICENSE TRAINING receive training for the Novice, Technician and General PRIVTED AmateuwillLicenses. You Classes of F.C.C. Radio CIRCUITRY will build Receiver, Transmitter, Square Wave Generator, Code Oscillator, Signal Tracer and Signal Injector circuits, and learn how receive an excellent background for television. to operate them. You Absolutely no previous Hi -Fi and Electronics. knowledge of radio or required. The "Edu -Kit" is the product of many years of teaching and engineering experience. SERVICING LESSONS provide you with The ' Etlu -Kit" ill a basic education in Electronics and Radio, worth many times the . low You price you pa The Signal Tracer alone is orth more than the Brice will learn troubleshooting and of the kit. servicing in a progressive manner. You will practice repairs on the sets that THE KIT FOR EVERYONE you construct. You will learn symptoms and causes Of trouble in home. portable You do not need the slightest background ages and backgrounds have and car radios. You will learn how to In radio or science. Whether you are inter- used the "Etlu successfully use the professional ested in Radio & Electronics because -Kit' in more than 79 coun- Signal Tracer. the ant you tries of the world. The Etlu -Nit" has been unique Signal Infector and the dynamic an interesting hobby, a well paying carefully designed, step by Radio & Electronics Tester. While you business or a job With a future- you will find make mistake. stela. so that are learning in this practical the 'Etlu -Nit" a worth -while investment. The Edu -Nit" you cannot taketeach yourself at own will be able to do many a repairalob for Many thousands of individuals of all rate. No instructor is necessary. your swillti neighbors, Charge fes which far exceed the price of the "Etlu- Nit." Our Consultation Service PROGRESSIVE TEACHING will help you with any technical prob- METHOD lems you may The Progressive have. Radio "Etlu -Nit" is the foremost iluc,Ilicoal radio kit in the world, and is universally accepted as the standard In the fields of iI,ctronics Klit" uses the modern educational principle training. The "Ed,:. learn schematics, of 'Learn by Doing." Therefore you construct, study theory, practice trouble shooting-all in a closely Integrated FROM OUR MAIL BAG gram designed to provide an easily-learned, thorough and interesting pro- You background in radio. begin by a mining the various radio parts of the "Edu- Kit." You J. Stataitis, of 25 Poplar PI., Water- function, theory ansk. wiring of these Then then learn the set parts. you build a simple radio. With this first bury, Conn., writes: I have repaired you will enjoy WIStening to regular broadcast stations, learn theory, practice several sets for my friends. and made and trouble -shooting- Then you build a more testing ' and techniques. advanced radio, learn more advanced theory moneThe Edu-Kit" paid for Itself. Gradually. in a progressive manner, and at your own rate, you was ready to spend $240 for a Course, find yourself constructing more advanced multi -tube radio circuits, will but Ir found your ad and sent for Drofessional Radio Technician, and doing Work like A Kit." your Included in the 'Edu -Kit" course are Receiver, Transmitter, Code Magna. Tracer, Square Wave Generator Oscillator, Signal Utah: Etlu breadboard" and Signal Injector Circuits. These are not unprofessional "The Kits arewonderful. ere periments, but genuine radio circuits, constructed by m of I am sending you the questions and also wiring and soldering professional an we for on metal chassis, plus the new method of radio construction known the them. I have been n as "Printed Circuitry." These circuits operate on our re ular AC Radio for the last Seven years, but like or DC house current. 0 work with Radio Kits, and Radio like to THE build Testing Equipment. I en- "EDU -KIT" IS COMPLETE joyed y minute I worked with the You receive different skits; the Signal Tracer works will all parts and instructions necessary to build twenty different radio and fine. Also electronics circuits, each guaranteed like to let you know that 1 to operate. Our Kits contain tubes, tubesockets, vari- feel proud Ol becoming a member of your able, electrolytic, mica, ceramic and paper dielectric condensers, resistors, Radio -TV Club." hardware, tubing, punched metal chassis, Instruction tie strips, selenium rectifiers. Manuals, hook -up wire, solder, Robert L. Shuff, 1534 Monroe Ave., coils, volume controls and switches, etc. Huntington. W. Va.: Thought I would In addition, you receive Printed Circuit materials, drop you a few lines say special tube sockets, including Printed Circuit chassis, to that I re- hardware and instructions. You also receive a useful ceived my Etlu -Kit, and was really amazed professional electric set of tools, a a bargain Tester. soldering iron, and a self- powered Dynamic Radio and Electronics that such can be had at such The "Edu -Kit" also includes Code a price. I have already Started e- in addition Instructions and the Progressive Code Oscillator, pairing to F.C.C. Radio Amateur License training. You radios and phonographs. My will also receive lessons for friends a really surprised to see me Fidelity and Quiz Book. You get into the swing of it So quickly. The tion Service, re ive Membership in Radio -TV Club. Free Consulta- Trouble- shooting Tester Certificate of Merit and Discount Privileges. You receive that comes with instructions, etc. Everything is yours to keep. all parts, tools, the Kit is .ally Swell. and finds the trouble, if there Is any to be found," Progressive "Edu -Kits" Inc., 1186 - Broadway. Dept. 556 NN, Hewlett, N. Y. 11557 UNCONDITIONAL MONEY -BACK GUARANTEE---- - Please rush my Progressive Radio "Edu -Kit" to me, as indicated below: PRINTED Check one box to indicate choice of model CIRCUITRY Regular model $26.95. At no increase Deluxe in price, the "Edu -Kit" model $31.95 (same as regular model except with now includes Printed Circuitry, You build and superior parts a tools plus valuable Radio & TV Tube Checker). Printed Circuit Signal Injector, a unique servicing Check one box to indicate manner of payment instrument that can detect malty I enclose full payment. Radio and TV troubles. This revolutionary Ship "Edu -Kit" post paid. new r] I enclose $5 deposit. technique of radio construction is new Ship 'Edu -Kit" C.O.D. for balance plus postage. becoming Send me FREE additional popular in commercial radio and information describing "EduKit." TV sets. Name A Printed Circuit is a special insulated chassis on which has been deposited a con- Address ducting material which takes the place of wiring. The various parts are merely plugged City & State in and soldered to terminals. Zip Printed Circuitry is the basis of modern PROGRESSIVE "EDU -KITS" INC. Automation Electronics. A knowledge of this 1186 Broadway, Dept. subject is a necessity today for anyone in- 556 NN, Hewlett, N. Y. 11557 terested in Electronics.