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Chairman of the Board 19.10- POPULAR ELECTRONICS is pu'.dished monthly by Ziff -Davis 1954 et the Post 'Jence. Chicago, Illinois. 1053), t 64 E. Lake St., Chicago 1. III. Entered as second class matter August 27, all foreign L.S. and possessions, and Canada Pan -American Union Countries $3.50: otter SUBSCRIPTION RATES: One year countriesCna $3.00l 3 August, 1955 AmericanRadioHistory.Com AUGUST 1955 POPULAR VOL. 3- NUMBER 2 EDITOR OLIVER READ, W1ETI MANAGING EDITOR O. P. Ferrell ELECTRONICS TECHNICAL EDITOR H. S. Renne Registered L. S. Putout 011ue FEATURE EDITOR Norman Eisenberg CONTENTS ASSOCIATE EDITORS M. C. Magna Charles Tepfer Automatic Factories E. G. Louis 21 ART EDITOR A. Reich Electronic Fish -Finders 27 J. CONTRIBUTING EDITORS Behind the U.L. Label E D. Morgan 31 J. T. Frye L. E. Garner, Jr. H. Bennett R. P. Turner Science Meters a Heart Muscle 34 R. Legge H. Pollack "Mr. Meticulous" Makes Transistors 37 H. S. Brier "Over the ART DEPARTMENT Horizon" Transmission 39 Frank Sayles (Director) TV for J. A. Golanek M. Whelpley Parking Lots 41 ADVERTISING DEPARTMENT Using the CdS Photocell Marvin Lubin and Wallace Samuelson 42 NEW YORK (MU 7-8080) Lingo of the Schematic L. L. Osten -Adv. Dir. George Berry 44 Wm. G. McRoy-Adv. Mgr. Positive T. Suito Flash -Gun Tester Harvey Pollack 46 Build Your Own Applause CHICAGO (AN 3.5200) Meter Louis E. Garner, Jr. 47 James Weakley Checking a Typical Clock Radio. H Leeper 52 LOS ANGELES (Mich. 9856) Build John E. Payne -W. J. Fitzgerald Your Own Geiger Counter Probe Carter Robertson 54 Electronic FF'DAl- "Whistler".. Rufus P. Turner 57 Jig Makes Solder Gun Tips Z Copyright 1955 Harvey Pollack 62 (AB Rights Reserved) The $1.60 Signal Generator Frank H. Tooker 64 /NG & Carl Jerry. John T. Frye 66 ZIFF -DAVIS Printed Circuitry for R/C Paul F. Runge 74 Thin PUBLISHING COMPANY -Skin Chassis Cuts Costs Richard C. Saunders 90 W. B. ZIFF (1898.1953) FOUNDER POPULAR ELECTRONICS Audio and Hi-Fi Section Also Publishers of RADIO & TELEVISION NEWS Disc and Tape Review Bert Whyte 77 Editorial and Executive Offices Birth of a Loudspeaker 79 366 Madison Ave., New York 17, N.Y. Distortion in Hi -Fi Equipment (Part 3) Norman H. Crowhurst 82 PRESIDENT B. G. DAVIS What Is an Audio Watt?. Eugene F. Coriell, Major, USAF 84 VICE -PRESIDENTS Square -Wave Converter... Howard J. Carter 86 H. J. MORGANROTH M. FROELICH SECRETARY-TREASURER DEPARTMENTS G. E. CARNEY MANAGER From the M. Ed. of POP'tronics 8 CIRCULATION M. MICHAELSON Letters from Our Readers 10 BRANCH OFFICES The Chicago 64 E. Transmitting Tower Herb S. Brier 68 (1), Lake St. Los Angeles (1 4), Stotler Center, Ama- Touring with Roger Legge 70 900 Wilshire Blvd. Tuning the Short -Wave Bands Hank SUBSCRIPTION service: Bennett 71 All communications concerning mute Iptlonn should be addressed to Cir- R/C Notes 73 crculation Dept.. 64 E. lake St.. Chicago I . Ill. 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