Radio broadcast .. (1922-30)

RADIO BROADCAST WILLIS K. WING, Editor JUNE, 1926 «i KEITH HENNEY, Director of the Laboratory JOHN B. BRENNAN Technical Editor Vol. IX, No. 2 -fn Cover Design From a Painting by Fred ]. Edgars Frontispiece The Antenna of the London Broadcasting Station How New York Talks to London Edgar H. Felix The March of Radio /. H. Morecroft The "Radio Broadcast Lab." Circuit Keith Henney How to Pack Radio Sets for Shipment Stanley W. Todd Some Receivers in the $500 S. W. Contest * * .* •» Progressive Modifications in the Silver Model 1926 Receiver ' The Laboratory Staff The Listeners' Point of View John Wallace Cutting Out the Locals Howard E. Rhodes A Simple Radio Test Set ' Sid Goodwin Some New Apparatus * * » * * * How Wire Lines for Broadcasting Are Equalised "As the Broadcaster Sees It." Carl Dreher Drawings by Stuart Hay "Radio Broadcast's" Booklet of American and Cana' dian Broadcasters *.**•* Lawrence W. Corbett The "Radio Broadcast" Laboratory Information Sheets No. i. Regeneration No. a. Factors Governing Radio Reception No. 3. The Browning-Drake Receiver Data No. 4. The Browning'Drake Circuit No. 5. Transformers No. 6. Dielectric Constant No. 7. The New Tubei No. 8. Condensers "Now, I Have Found" A Wooden Stand to Hold a Machinist's Drill A Simple Cone Loud Speaker Adjustment A Winding Form for Roberts Low Loss Coils An Improved Radio Reproducer A Better Method of Winding Inductance Coil» The Correct Method of Wiring Insulators A Collapsible Antenna A Marker for Battery Leads Eliminating Oil Burner Interference The New "Radio Broadcast" Laboratory Service for Readers **•»•.* *^* Book Review ' ' Walter Van B. Roberts Practical Radio, by Moyer and Wostrel A Key to Recent Radio Articles E. G. Shaltyiauser Weather Forecast Transmissions A Neglected Angle of the Radiation Question Harold Jolliffe Letters from Readers ,,,'**'' no in 116 121 126 128 130 133 138 143 146 I48 153 166 172 175 176 177 181 182 185 BEHIND EDITORIAL SCENES MUCH interest has been aroused on both sides of the Atlantic by the press announcements of successful transatlantic radio telephony, combined with the regular wire line system. Aside from that other startling feat — the transmission of photographs by radio, it is doubtful if any radio achievement has attracted as much recent attention, or given rise to as much speculation about the future, as has this development in the transatlantic field. One of the first questions naturally asked is, " How is it done? " Edgar Felix's article, in this number, tells just what the technical background of this remarkable telephonic achievement is. Professor Morecroft explains in the leading article in "The March of Radio" this month just what the much-discussed crystal frequency control is, which should answer the questions of many radio experimenters. . . . On page in, appears an article on the "Radio Broadcast Lab." Circuit, which we guarantee will provide the experimenter with some constructional ideas of an altogether different sort from those he usually finds in radio publications. THE Listeners' Point of View this month contains the amusing and very true and keen observations of some of our best-known humorists, including the irrepressible Will Rogers. . . . Those who have had opinions without any actual facts about the "blanketing" effect of high power broadcasting stations will be interested in Howard Rhodes's article about tests made by the technical staff of RADIO BROADCAST in and around Bound Brook, New Jersey, the home of wjz. Particular attention is called to the complete list of Canadian and American broadcasting stations which is so arranged that it may be clipped out and kept for constant use in booklet form. The list is as complete and accurate as it is possible to make it. Another innovation appears in the RADIO BROADCAST Laboratory Information Sheets which, beginning with this issue, take the place of the former "Grid" department. The announcement of the expansion of the Laboratory services on page 175 should also be of great interest to our readers. THE July RADIO BROADCAST, on sale June ly, will contain an article describing the use and construction of a corn* bined high-quality amplifier and B current supply unit. There will also be other announcements of great interest to all those interested in short-wave work. A Radio Club of America paper, dealing with improvements in radio receivers, is also on the July schedule. Julian Aceves, research assistant to Professor Pupin of Columbia University, is author of the paper. Another article for the home laboratory experimenter, written by Keith Henney, will appear in an early number of RADIO BROADCAST and describes the use and construction of a useful heterodyne wavemeter, an instrument which is of great value around the laboratory of the home experimenter. Doubltday, Page & Co. MAGAZINES COUNTRY LIFE WORLD'S WORK GARDEN & HOME BUILDER RADIO BROADCAST SHORT STORIES EDUCATIONAL REVIEW LE PETIT JOURNAL EL Eco THE FRONTIER WEST Doubleday, Page Sr Co. BOOK SHOPS (Books of all Publishers') (LORD & TAYLOR BOOK SHOP PENNSYLVANIA TERMINAL (2 Shops) 38WALLST.AND |66WEST J2NDST. GRAND CENTRAL TERMINAL ( 223 NORTH STH STREET : 1 4014 MARYLAND AVENUE tf .vis.* PITV fs20 GRAND AVENUE KANSAS CITY, j ^ WEST 47TH STREET CLEVELAND' HIGBEE Co. SPRINGFIELD. MASS.: MEEKINS, PACKARD& WHEAT NEW YORK: Doubleday, Page &r Co. OFFICES GARDEN CITY, N. Y. 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