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RADIO BROADCAST ARTHUR H. LYNCH, Editor 1925 WILLIS K. WING, Associate Editor DECEMBER, JOHN B. BRENNAN, Technical Editor Vol. VIII, No. 2 BEHIND THE EDITORIAL SCENES - new and enlarged RADIO BROADCAST has met with almost Cover From a Painting by Fred J. Edgars Design THEuniversal favor and its reception was even more hearty than the had dared In New York the Radio Enters the Club - publishers hope. City alone, Frontispiece supply of the November number was exhausted four days after How Radio Grew Robert H. Marriott 159 it was placed on sale. Copies of the number are so rare that we Up haven't more than three copies in the editorial offices for our own use. Letters from readers all over the have been most Tubes: Their Uses and Abuses - - Keith Henney 163 * country generous in praising the appearance and contents of the November - - - - number. The March of Radio J- H- Morecro/t 167 H. MARRIOTT, whose article, "How Radio A Five'Tube Receiver of Dual Efficiency ROBERTGrew Up" leads this issue, is one of the old men of wireless Glenn H. Browning 172 in the United States. He was the first president of the Insti- tute of Radio Engineers, was one of the first radio inspectors to be The Listeners' Point of View Kingsley Welles 177 appointed after the radio law of 1912 was passed. For a long time he was expert radio aide at the Bremerton Navy Yard, Short Waves A New Paradise for the DX Fan Washington, and is now a consulting radio engineer in New York. who writes about short in Edgar H. Felix 182 Edgar Felix, waves this number, was for several years publicity representative of Plans for the Third of the International Radio Broad' station WEAF in New York. Glenn H. Browning, who with his inseparable technical partner, Mr. F. H. Drake, has become cast Tests **.** Arthur H. Lynch 185 nationally known for the Browning-Drake receiver, describes a great improvement over the early model in this number. Both Plate Current Unit An Improved Supply Mr. Browning and Mr. Drake are familiar figures around the Roland F. Beers 186 famous Cruft laboratory at Harvard University, where much of their work has been done. The valuable current periodical As the Broadcaster Sees It - - - - Carl Dreher 191 surveys, made by E. G. Shalkhauser, the first of which appeared in our November issue, are continued in this number. Many The "Aristocrat" Receiver: Resistance'Coupled readers have written us saying that these condensed surveys of the articles in this and in our '*..*' - 196 important appearing magazine Amplification contemporaries are of great value to them. in Receiver How to Use Meters Your James Millen 198 January RADIO BROADCAST will contain an article by THEArthur H. Lynch telling how to build "RADIO BROADCAST'S New Fields For the Home Constructor Universal Receiver." The set he describes is an unusual and Keith Henney 201 very efficient combination of standard parts and it is doubtful if there is any receiver its superior in point of sensitivity and "Now, I Have Found" 206 quality. It is not a "freak" outfit in any sense. Kendall of will have an article about the of Tracing Radio Noises Clough Chicago principles A Ratchet Coil Winder audio amplification which is of particular interest. The author for the Roberts Circuit A Coupling Device weighs and casts aside some of the commonly accepted theories A File for Ideas of amplification. We believe the article will attract a deal Super-He'erodyne Noises great of attention. Wallace Checkii t* up on B-Battery Leakage Mr. John of Evanston, Illinois, will from A Vark meter for the Roberts Set now on write the "Listeners' Point of View." With his central Mr. Wallace is able to hear broadcast How to Eliminate Local Interference - - 212 location, offerings in almost every part of the United States and Canada. Our new broadcast critic is an versatile for he is a writer A List of Australian Stations 224 unusually person, Broadcasting of great charm and not a little wit. as well as an artist of consider- able In his his and humorous The Grid and Answers - - 226 ability. college days, drawings Questions "pieces" appeared in the Cornell Widow. Coil Placement in an R. F. Amplifier Precautions in Antenna Erection r ( T" HE advertising pages of the magazines of the "Quality Measuring the Resistance of Coil Units JL Matching Tubes and R. F. Coils Group," that is, the Atlantic Monthly, Harpers, Review of Reviews, Scribners, and the World's Worf; now contain only the A Key to Recent Radio Articles E. G. Shalkhauser 232 announcements of those radio manufacturers whose products have been tested and approved by the Laboratory of RADIO - - - Is Your Set a Blooper? 238 BROADCAST. Readers of those magazines who are not well versed in matters radio have the privilege of calling on the technical What Our Readers Write Us 244 staff of this magazine for help and advice. Doubleday, Page Sr Co. Doubltday, Page fir Co. BOOK SHOPS Doubleday, Page & Co. Doubleday, Page & Co. MAGAZINES TAYLOR BOOK OFFICES OFFICERS ("LORD & SHOP COUNTRY LIFE I PENNSYLVANIA TERMINAL GARDEN CITY, N. Y. NEW YORK: (2 Shops) F. N. DOUBLEDAY. President WORLD'S WORK I 38 WALL ST. NEW YORK: 120 WEST 32ND STREET GARDEN & HOME BUILDER (.GRAND CENTRAL TERMINAL A. W. PAGE, Vice-President RADIO BROADCAST NORTH STH STREET BOSTON: PARK SQUARE BUILDING ST. Louis: NELSON DOUBLEDAY, Vice-President SHORT STORIES [2234914 MARYLAND AVENUE CHICAGO: PEOPLES GAS BUILDING EDUCATIONAL REVIEW GRAND AVENUE RUSSELL DOUBLEDAY, KANSASAS CITY,rrrv t 920 SANTA BARBARA, CAL. Secretary LE PETIT JOURNAL j Jo6 WFST 4?TH STREET A. Treasurer EL Eco TOLEDO: LASALLE & KOCH LONDON: WM. HEINEMANN LTD. S. EVERITT, THE FRONTIER CLEVELAND: HIGBEE Co. TORONTO: OXFORD UNIVERSITY PRESS JOHN J. HESSIAN, Asst. Treasurer SPRINGFIELD, MASS. : MEEKINS, PACKARD & WHEAT DOUBLEDAT, PAGE & COMPACT, Garden Qity, ^[ew Copyright, 1925, in the United States, 'Newfoundland, Great Britain, Canada, and other countries by Doubleday, Page & Company. AH rights reserved. TERMS: $4.00 a year; single copies 35 cents. '54 RADIO BROADCAST ADVERTISER 157 // **> V.VG . oa in <Madio Emphatically Yes! Radio IS marching forward, this season as before. But it is marching in a new direction. Quality of Reception. the That is the big, new theme. And new Jewett Receiver is its inspiration. The Jewett Receiver Three simple controls provide dis- At last Radio commands a Receiver that is truly a tortionless reception and eliminate all receiver noises The most richly beau- Musical Instrument, by a manufacturer of experience tiful Receiver you have ever seen. in the musical instrument field. The Jewett Superspeaker Recom words cannot describe this new All that the name implies. Mere Jewett Quality mended by experts everywhere. of You must hear and understand. Reception. The Jewett Superspeaker Dealer let him Console So just visit an authorized Jewett and A handsome cabinet with Super- to that here is a new kind of Radio so prove you speaker performance. .different from the old as to create new standards and The Jewett Cone ideals. Faithful in tone and pitch regardless of heat, cold, or dampness. Semi-ad- dis- For the first time, B-Battery current and resulting justable. have been barred the tortion completely from speaker The Jewett Vemco Unit circuit. Makes a loud speaker out of your phonograph. You should know the story of this epoch-mark- Cabinet ing Receiver and its birth in the brains of our The Jewett Parkay straight-thinking young engineers who refused Puts the amateur on a par with the most exclusive cabinet worker. to admit that it couldn't be done. Ask us for it. The Jewett Micro-Dial "There Is No Substitute For The Best" Makes tuning 50 times as accurate. JEWETT RADIO & PHONOGRAPH CO. Fits any standard receiver. 5672 TELEGRAPH ROAD PONTIAC, MICHIGAN The Jewett Superspeaker Factories: Allegan, Michigan Pontiac, Michigan Highboy In Canada: Jewett Radio-Phonographs, Ltd., Walkerville, Ontario Houses any standard Radio set and built in. Export Sales Offices: 116 Broad Street, New York City all batteries. Superspeaker "Quality Broadcasting to Match Quality Products Special Wednesday Station WJR" WJR feature The Burroughs Hour, 9 to 10 p. m. 1925 Jewett Radio & Phonograph Co Tested and approved by RADIO BROADCAST RADIO ENTERS THE CLUB The installation at the Cornel! Club in 'Nfw Tor); City. The Western Electric super-heterodyne tfith peanut tubes is shown in the the top view at the left. A four-tube amplifier below intensifies the energy which is supplied to the loud speakers on panelled uialls of the various rooms. Employees of the Club are shown listening to the first test of the equipment. A public address system is also installed. Microphones picf( up the speeches mhich are carried to all parts of the club through the loud speakers RADIO BROADCAST VOLUME VIII NUMBER 2 DECEMBER, 1925 Grew Up Many Little Known Facts About Radio Development are Related Here Is the First of a Series of Articles on This Subject Written by a Pioneer in Wireless By ROBERT H. MARRIOTT First President Institute of Radio Engineers EPEATEDLY during the last one ers have received little compensation for pay. Some of those people need the money, hundred years, radio has been their work in the past and they are not in others do not; some are dead while those referred to as new, which has a position to collect now. The public still alive do not expect to realize anything had the result of making people owes a debt to many people which it cannot on their past labors. come to the conclusion that it must be new. The changes in radio development may This is, of course, very confusing, and is often be traced to unexpected causes.
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