Revised List of Broadcasting Stations The "Brief- Case" Single -Tube Loop Set Why Life is Interesting to a ,s Nod Commercial Operator "Neutrodyne" Receiving System Dry Cells and WD-11's Transmitting and Receiving with the Same One -Tube Set ;"1"14!.-c 17111# .,,, 25 Cents Published by DOUBLEDAY, PAGE & CO. Garden City, N. Y. www.americanradiohistory.com -,....armenan.rminSaW7M1.-MVAr- Tubes for Every Requirement Vacuum tubes are used for two distinct individual purposes in a receiving set -as DETECTORS and as AMPLIFIERS. The qualifications of a tube for these two uses are so different that for maximum efficiency tubes of entirely different design must be used. This point was one of the chief considerations of the research engineers who designed Cunningham tubes in the great laboratories of the General Electric Company. After years of research and experimental work, the Cunningham C -300, a SUPER -SENSITIVE DETECTOR, the Cunningham C -301, a DISTORTIONLESS AMPLIFIER, and the Cunningham C -301A, a LOW FILAMENT CURRENT AMPLIFIER, were developed. These three tubes, now nationally recognized as standards for all types of receiving sets, are responsible for the highly perfected results obtainable in radio phone reception. TYPE C -300 TYPE C-301A Super- Sensitive Amp. Fil- Current DETECTOR$500 Amplifier and Detector The trade mark GE is the guarantee of these quality tubes. Each tube Cunningham tubes are is built to most rigid Patent Notice - covered by patents sp_cifications. dated 11 -7 -05, 1- 15 -07, 2- 18 -08, and others issued and pending. Licensed for amateur, experimental, and entertainment use in radio commu- nication. Any other use will be an infringement Home Office: 248 First Street Eastern Representative: San Francisco, Calif. 154 West Lake St., Chicago, Illinois * Tested and approved by RADIO BROADCAST * www.americanradiohistory.com RADIO BROADCAST ADVERTISER TT IS but natural that Kennedy Receiving Sets i are found in the finest homes. The same ap- preciation of artistry that is responsible for beauti- ful home surroundings sees in a Kennedy a fitting example of craftsmanship that belongs with the finest. Again-the clarity of reception, freedom from extraneous noises, and greater elimination of inter- ference made possible by a Kennedy appeals to the true lover of music and the finer things of life. The long range places the music of the continent within your reach. And last -the owner of a Kennedy. knows that That the Kennedy "Universal" will it. possession set is a wonderful example of others admire Its reflects good mechanical excellence is shown taste and judgment. by this interior view. It can be made to detect, regenerate or oscillate over its entire range of ilrrange with your local dealer 200 to 25,000 meters. for demonstration, or write us direct for descriptive literature. /111 Kennedy Regenerative Re- ceivers are licensed under llrnt- strong U. S. Patent No. 1,113.- THE COLIN B. KENNEDY COMPANY 149. SAINT LOUIS SAN FRANCISCO *KENNEDY i7h»cRayac y `of'2adio * Tested and approved by RADIO BROADCAST * www.americanradiohistory.com Radio Broadcast ARTHUR 11. LYNCH, EDITOR CONTENTS FOR MAY, 1923 Herbert C. Hoover, Secretary of Commerce Frontispiece THE MARCH OF RADIO 3 A SINGLE -TUBE LOOP SET IN A BRIEF -CASE WALTER VAN B. ROBERTS 16 CONFESSIONS OF AN UNMADE MAN R. O. JASPERSON 20 Drawings by Thomas E. Monroe RADIO AS A RENT INDUCEMENT ALLISON EURAY 22 THE "HAM" SET OF AN OLD SHIP OPERATOR ZEH BoucK 23 THE TUNING TROUBLES OF MESSRS. GALLAGHER AND SHEAN - A. G. CLARK 28 TRANSMITTING AND RECEIVING WITH THE SAME ONE -TUBE SET FREDERIC W. PROCTER 29 HAVE YOU HEARD THESE STATIONS YET? 33 SUPPLYING BROADCASTING LIKE GAS OR ELECTRICITY GRAYSON L. KIRK 35 THE "NEUTRODYNE" RECEIVING SYSTEM KIMBALL H. STARK 38 AN S O S IN THE JUNGLE OF INDO -CHINA LELAND L. SMITH 42 ADDING TWO STEPS TO YOUR AERIOLA SENIOR JACQUES H. HERTS 52 WHAT CAN BE PATENTED? ROGER SHERMAN HOAR i5 Drawings by Thomas E. Monroe LISTENING TO A BROADCAST PROGRAM A fHOTEL BELLEVUE, SAN FRANCISCO 6o A RADIO CODE WITH ELEVEN MILLION VARIATIONS S. R. WINTERS 62 AMONG THE "HAMS" 64 ALL BOY SCOUTS, ATTENTION! 66 WHY LIFE 1S INTERESTING TO A COMMERCIAL OPERATOR A. HENRY 67 THE BROADCAST RECEIVING CONTEST-RULES AND PRIZES 73 SIX -INCH DRY CELLS AND WD -11 TUBES E. E. HORINE 74 REVISED LIST OF ALL U. S. AND CANADIAN BROADCASTING STATIONS 78 THE GRID-QUESTIONS AND ANSWERS 79 NEW EQUIPMENT 88 Copyright, 1923, by Doubleday, Page & Co. All rights reserved TERMS: $3.00 a year; single copies 25 cents r. N. DOUBLEDAY, Pres. ARTHUR W. PAGE, Vice -Pres. NELSON DOUBLEDAY, Vice -Pres. RUSSELL DOUBLEDAY, SeC'y. S. A. EVERITT, Treas. JOHN J. HESSIAN, Asst. Treas. DOUBLEDAY, PAGE & CO. THE WORLD'S WORK COUNTRY LIFE THE GARDEN MAGAZINE SHORT STORIES EDUCATIONAL REVIEW HEALTH BUILDER CHICAGO: People's Gas Bldg. GARDEN CITY, N. Y. NEW YORK: 120 W. 32nd Street L BOSTON: Tremont Bldg. LOS ANGELES: Van Nuys Bldg.. a www.americanradiohistory.com Exidé BATTERIES Uniform current cuts out the noise EVERY radio amateur knows how disastrous battery noises are to clear receiving. You can avoid this an- noying interference by getting the bat- tery that insures a steady flow of fila- ment current. That battery is the Exide Radio Battery. This specially designed radio battery does its work uncomplainingly, and never requires much attention. The rasping, snarling noises often caused by fluctuating current in ordi- nary batteries do not exist in the Exide Bat- tery. It delivers uniform filament current for every type of vacuum tube. You can count on the Exide for dependable, long -lasting service. Exide Batteries are used in a majority of the government and commercial wireless stations and in every industry where a battery's re- sponse to the call of duty must not fail. Any dealer in radio equipment will sell you an Exide Radio Battery, or you can get one at the nearest Exide Service Station. THE ELECTRIC STORAGE BATTERY CO. Philadelphia, Pa. Service Stations Everywhere Branches in Seventeen Cities * Tested and approved by RADIO BROADCAST * www.americanradiohistory.com Q Paul Thompson HERBERT C. HOOVER, SECRETARY OF COMMERCE The White Radio Bill failed at the last session of Congress, but the radio world is now looking to Secretary Hoover to make the best of a bad situation by regulating wavelengths in so far as his present authority allows www.americanradiohistory.com RADIO BROADCAST Vol. 3 No. I Mav. 1923 INV Iiirr The _March of Radio WHAT RADIO BROADCAST IS TRYING TO DO THIS is our first anniversary number. Much of our present radio development is The twelve issues of RADIO BROAD- directly traceable to that. geoup of electrical CAST which have preceded this repre- experts whom we call, for lack of a better sent twelve efforts to give you the name, "amateurs-." There are those who very best magazine we could make. would terminate the activities of these experi- It is evident that no uncertain policy, no waver- menters, but in our opinion such a procedure ing of ideals, and no subordination to any selfish would be not only unjust, it would be folly, for interest can lead to the highest usefulness of this certain of the amateurs' activities are con- or any other publication. We believe that you ducive to great benefits to radio. will be interested in a brief statement, at this Concerning broadcasting, this phase of our time, of just what we stand for, what we have game is at once the most interesting . and been trying to do, and what interests RADIO popular. Broadcasting has done mre to ad- BROADCAST will continue to serve. We believe: vance radio in the last two or three years than That the most important function of radio all the efforts of previous years. Of course, is to make life safe at sea; there is much to be desired in broadcasting as That closer and more friendly relations we find it to -day. We need improved trans- between the United States and other nations mission, better programmes, adequate wave- can and should be fostered by means of radio length regulation, fewer high -power broadcast- communication; ing stations,a more satisfactory distribution of That in broadcasting we have a tre- transmitting stations, a reasonable standard- mendous force which, properly directed, may ization of apparatus. be a means of incalculable and universal We have consistently endeavored to promote good; and that every effort should be made regulation of a helpful character. As you to see that this force is fairly and intelligently know, you and we have campaigned together used for the benefit of the greatest number. for legislation designed to bring about the It is our intention to continue a policy changes necessary for better broadcasting. which is consistent with these beliefs. First, Thus, you will see that last, and always, we are for "Better Radio." We RADIO BROADCAST is, in a make mistakes, but believe that those who do sense, not our magazine -it not make mistakes, never make anything. Al- is yours. We are but players though you may not always agree with the ideas on a stage, interpreting to the we express, you can always be sure that we best of our ability for you, believe what we say and that we make every our audience, without whom effort to state the facts clearly and justly. there would be no play. www.americanradiohistory.com Radio Broadcast As the Radio Corporation Sees the communication with the principal foreign countries, Patent Situation making the United States the great centre and leading factor in world radio communication. To TI I E following letter from General Har- achieve these ends it has been obliged to coördinate bord, President of the Radio Corpora- the inventive genius of many individuals.