Published by Experimenter Publishing Company, Inc

Radio News for May, 1929

Volume 10 May, 1929 Number 11

ARTHUR H. LYNCH, Editor -in -Chief C. P. MASON, Associate Editor JOHN B. BRENNAN, Jr., Laboratory Director C. WALTER PALMER, Director Information Service

Contents of This Issue Aviation and Radio The Hammarlund- Roberts "Junior Hi -Q By Arthur H. Lynch 985 ' 29" By Leslie G. Biles 1009 Giant Speaker of Four -Mile Range By -Pass Resistors for Series-Filament By C. Sterling Gleason 986 'Operation By J. H. Arnold 1011 Public- Address Systems By J. E. Smith 988 The "A.C. Screen -Grid DX-er" What's New in Radio 992 By Robert Ilertzbcrg 1012 Radio "Mysteries" and Other Audio More About Harmonics of Long -Wave Effects 994 Broadcast Stations 1015 Increasing Selectivity in a Receiver Wavemeter Hints for the Short -Wave By C. Walter Palmer 995 Listener By A. Binneweg, Jr. 1016 How to Deal with "Man -Made Static" The Service Man 1018 By Tobe Deutschmann 998 Radio Wrinkles 1020 Choosing Between Volume -Control Meth- The Constructor's Own Page 1022 van ods By Ashur A. Sommers 1000 List of Broadcast Station Calls 1024 How to Build the New York Times On the Short Waves 1026 Short --Wave Receiver By F. E. Meinholtz 1002 RADIO NEWS Laboratories 1028 The Radio Beginner -A "Hartley" R.F. I Want to Know By C. W. Palmer 1029 Broadcast Receiver By B. B. Bryant 1006 4p Radio Book Review By H. M. Bayer 1052

IN THE FORTHCOMING ISSUES

For our June and following issues RADIO NEWS has In preparation. among others, the following articles of interest to our constructors: A NEW BROWNING CIRCT:IT. Professor Glenn H. Brown- A NEW TYPE OF SUPERHETERODYNE. This receiver. ing. co- inventor of the famous Browning- Drake. has de- the last achievement of the late R. E. Lacault, inventor of veloped new receiver employing the new U57-224 A.C. the Ultradyne. will appear in the near future, and be screen -grid tubes. On trial of this set in Boston, nine found of special interest. Pacific Coast stations were received on the loud speaker. It A MODERN SINGLE- CONTROL SCREEN -GRID RE- is designed to work with the new Millen "Velvetone" ampli- CEIVER. John B. Brennan, Jr.. formerly Technical Editor fier. A series of exclusive articles, covering the mathe- of "Radio Broadcast." will describe another very interesting matics, design and construction of this remarkable set will receiver especially adapted to present -day requirements In appear in the next few issues. home entertainers. THE " ELVETONE" 245 -TYPE AMPLIFIER, the first to SHORT -WAVE TRANSMITTERS. At the request of many use the new UY -245 A.C. 254 -colt power tube. designed by readers. RADIO NEWS will resume publishing articles on James Millen, will appear in June. It cives remarkable this subject, beginning with a low - powered (201A) outfit volume and quality with a 245 push -pull stage, and furnishes to give the amateur modest start at low cost. -B for a receiver. also "A -C" power AVIATION RADIO EQUIPMENT. The remarkable recent THE "EVERYMAN A.C. SCREEN -GRID FIVE," by Zell developments of apparatus of this type will be exploited Bowls, will be so described that it may be readily con - in the next few issues of RADIO NEWS; the Improved structed either as complete receiver or ss a tuning unit Radio Beacon. one of the most important adjuncts of com- to operate a separate power amplifier. mercial dying. will be described in the June kaue.

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