RADIO BROADCAST WILLIS KINGSLEY WING, Editor OCTOBER, 1927 KEITH HENNEY EDGAR H. FELIX Vol. XI, No. 6 Director of the Laboratory Contributing Editor =* AMO7S[G OTHER THINGS. - - - - Cover Design From a Design by Harvey Hopkins Dunn MUCH is now being accomplished in the complete set SOfield that beginning with this issue, RADIO BROADCAST Station the Frontispiece The Most Powerful Broadcasting in World 340 will devote much of its space to reflecting the technical and other advances being made. The policy of this magazine remains as Now You Can Receive Radio Pictures - - Keith tienney 341 before, to present the news of radio surrounded by as much as of what the technical radio worker refers to as The March of Radio An Editorial possible "dope." Interpretation 344 And much "dope" there is in this complete set side of radio as Modern Radio Receivers are a Good Invest- The of Direct on the Danger Advertising Air articles which will in issues will ment The Month in Radio many appear following strikingly demonstrate. In all the other fields of radio endeavor Listening to World-Wide Broadcasting is Licenses and What They Mean which Near The Columbia Broadcasting Chain RADIO BROADCAST has covered heretofore the construction A Profound Study of Radio Law of radio receiving apparatus, laboratory experiments, short- - wave communication, from the technical and The 1928 "Hi'Q" Has an Extra R. F. Stage John B. Brennan 348 broadcasting program side, and many others which we have covered to Manufactured Receivers for the Coming Season - - - 351 the satisfaction of our readers, RADIO BROADCAST will be as active as before. The expansion in scope of our text pages is 1928 Radio Receivers of Beauty and Utility - - - - - - 352 directly designed to keep our readers in close touch with all sides of radio. The Neutrodyne Group ,,.,,,, 354 Servants of Your Light Socket - - - - 356 A"\ /"HERE is the radio experimenter who has not read of the W rapid progress of the transmission of photographs by Radiolas for 1928 ,,,,,, j^g wire and radio and hoped that he would soon be able to share in the fascination of this new and intensely modern field? For for . Some New Offerings the 1928 Season 360 the past few years, RADIO BROADCAST has watched the progress of the art, hoping that devices would be developed within the New Tube - Millen A Regulator James 363 scope of the amateur laboratory and pocketbook. The leading article on page 341 describes the background of the Cooley The Receiver - - - - - - 1928 "Equamatic" Julian Kay 364 "Rayfoto" system which in a very few weeks will be made available the of RADIO BROADCAST to the home A New Principle of R. F. Tuning David Grimes 367 through pages experimenter. To be able to construct a radio photograph re- Book Review - Car! Dreher 369 ceiver for less than $100 should appeal very strongly to the who are for new to do. Using Radio in Sales Promotion, by Edgar H. Felix experimental fraternity crying something Here, in a manner of speaking, it is. 1928 Loud Speakers - , , , . , j^o Should the Small Station Exist? John Wallace 372 pages of this issue are devoted to showing the "The Listeners' Point of View" MANYofferings of the set makers for the coming season. Later issues of this magazine will describe in greater detail interesting Your A. C. Set - - H. Felix Edgar 374 technical features of these many receivers from many manufac? turers. As the Broadcaster Sees It - Carl Dreher 376 Transformers and Chokes for Home-Constructing Power-Supply r > T" HOSE of a technical turn of mind will read with great Devices - - Homer S. Davis 379 J. interest David Grimes' story on page 567 describing the theoretical features of a radio receiving system which is one cf "Radio Broadcast's" Laboratory Information Sheets - - - - - 388 the most interesting that has come to our attention in many No. The Glow Tube No. Care of Power Units 109 Type 874 133 Supply moons. Articles to follow by Mr. Grimes will describe the No. 130 Data on Honeycomb Coils No. 134 Loud Speaker Horns circuit constants and information about the No. 131 Resistance-Coupled Amplifier No. 135 Closely Coupled Circuits practical system. No. 132 Resistance-Coupled Amplifier Circuit No. 136 Carrier Telephony Manufacturers' Booklets Available - - - - 394 Federal Radio Commission is making every effort to THEpopularize the use of the expression "frequency in kilo- Shall I - What Kit Buy? 396 cycles" instead of the familiar "wavelength in meters." It is hard for some, but one's in does to Recent Radio Articles going doing thinking kilocycles A Key .*<..>.. 398 remove serious from calculations. Ever since many complications - - its issue RADIO BROADCAST has "Radio Broadcast's" Directory of Manufactured Receivers 402 August, 1915, standardized the use of kilocycle designations, always printing at the same time, Making Radio Installations Safe Edgar H. Felix 410 the equivalent wavelength in meters. We are in sympathy with the wishes of the Radio Commission and invite the expression Book Review - 416 of our readers on this subject. Practical Radio Construction and Repairing, by Moyer and Wostrel WILLIS KINGSLEY WING. Doubleday, Page & Co. Doubleday, Page & Co, Doubleday, Page & Co. Doubleday, Page & Co. MAGAZINES BOOK SHOPS OFFICES OFFICERS all COUNTRY LIFE (Books of Publishers) GARDEN CITY, N. Y F. N. DOUBLEDAY, President WORLD'S WORK I LORD & TAYLOR BOOK SHOP NEW YORK: 285 MADISON AVENUE NELSON DOUBLEDAY, Vice-President GARDEN & HOME BUILDER \ PENNSYLVANIA TERMINAL (2 Shops) RADIO BROADCAST NEW YORK: -/GRANT CENTRAL TERMINAL BOSTON: PARK SQUARE BUILDING S. A. EVERITT, Vice-President SHORT STORIES J 38 WALL ST. and 5^6 LEXINGTON AVE. ' CHICAGO: PEOPLES GAS BUILDING RUSSELL DOUBLEDAY, EDUCATIONAL REVIEW 848 MADISON AVE. and 166 WEST 32NDST. Secretary LE PETIT JOURNAL ST. Louis: 223 N. 8TH ST and 4914 MARYLAND AVE. SANTA BARBARA, CAL. JOHN J. HESSIAN, Treasurer EL Eco KANSAS CITY: GRAND AVE. and 206 W. ST. 920 47TH HEINEMANN LTD. A. Asst. FRONTIER STORIES CLEVELAND: HIGBEE Co. LONDON: WM. LILLIAN COMSTOCK, Secretary "WEST SPRINGFIELD, MASS.: MEEKINS. PACKARD & WHEAT TORONTO: OXFORD UNIVERSITY PRESS L. J. McNAUCHTON, Asst. Treasurer OOUBLEDAT, PAGE & COMPACT, Garden Qity, X[ew Copyright, 1927, in the United States, Newfoundland, Great Britain, Canada, and other countries by Doubleday, Page & Company. All rights reserved. TERMS: $4.00 a year; single copies 35 cents. 338 RADIO BROADCAST ADVERTISER 339 strides made in the thing available if we do not make use of it. It past few years by the can now be utilized very simply. Radio artists, THEbroadcasting stations in editors and many musicians have expressed both bettering the quality of their pleasure and amazement on hearing the tone transmission have been remark- portrayal of symphony orchestras, as well as jazz able. The same principles have bands which Nature's Sounding Board has made been applied to the phono- possible. graph, resulting in the new rec- Nature's Sounding Board is known as the Lata ords and machines which are Balsa Reproducer. It is more than a "loud miles in advance of the older speaker." It is science's latest contribution to type. the musical art. It will make any good radio re- These improvements are now ceiver sound much more natural and pleasing. Lata Balsa Reproducer available to every listener-in. Lata Balsa Reproducers are available in com- Model 150, Price $50 However, there are some radio pleted, artistically decorated models ranging in receivers which will not reproduce price from $30. to $50. Kits are the wonderful music being broad- also available in two sizes. The fa- cast by the improved stations. mous Lata Unit, or electrical driv- By applying the same principles ing mechanism is now ready for to radio receivers which have delivery and is ideal for use with proved so helpful in the broad- the Lata Balsa Reproducer Kits. casting and phonograph fields it The accompanying illustration is now possible to make the most will give you some idea of the at- out of the broadcasting. By utili- tractiveness of the reproducer the scientific aids now avail- Everything necessary for the building of a to realize its tone zing modern three-stage resistance coupled am- superior quality able old and new receivers be plifier which may be applied to any re- must hear it. may ceiver. 59.00 you made to produce music which in The Lata Balsa Kits are com- every way resembles the original, There is as plete and may be assembled in a very short time by much difference between this new form of repro- anyone. No mechanical skill or electrical knowl- duction and the old as there is between the new edge is required to follow the simple instructions. phonograph and the old scratchy, squawky Once you have cylinder machine of yesteryear. heard this won- Resistance coupling simplifies receiver amplifier derful repro- construction and greatly reduces the cost. It is ducer no other recognized by leaders in the search for the best will satisfy you. tone quality as being the ideal amplifying system. The coupon be- It permits the passage of the very low notes and low is for your the very high ones with the same ease. It brings convenience in to the loudspeaker a true but greatly amplified ordering. Use it picture of what is picked up from the broadcast- today and you The number 2 station. re- Lata Balsa Kit and Reproducer ing will never unit assembled. You can duplicate this as- in a short is little in sembly very time by using this kit There use having this wonderful gret it. and complete instructions RETURN THIS COUPON- ARTHUR H. LYNCH, Inc. General Motors Bldg. 1775 Broadway BALSA ARTHUR H. LYNCH, inc. At 57th Street, New York City WOOD Gentlemen: General Motors Building REPRODUCER, Please send me the items checked, for which I enclose my Corp.