Radio Broadcast (Nov. 1925-Apr 1926)

246 RADIO BROADCAST ADVERTISER Super adio Receiver 5 Tubes 2 Dials $56 Licensed Under Reactodyne Agreement At last — true beauty is combined with scientific design so that results never before expected are now easily achieved. Loose, extravagant claims are not made for this set, which must be seen and heard to be appreciated. Results Undreamed of Now Secured Employs a radically new principle — inductive reaction. Housed in a handsome' compact, solid walnut cabinet with black bakelite panel engraved in deep goldProduces full rounded tones with all their color and shading. Oscillations automatically controlled. Use of low loss S. L. F. Condensers and highly developed Solenoid R. F. Transformers results in tremendous power without disturbing squeals, while simple controls, only two, regulate the thunderous volume to fairylike whispers, if desired. Send for circular giving engineering details why the Superadio is so far ahead of present day conceptions. Tested Tubes Now Possible With the Superadio Dynometer Remember — you can now buy TESTED tubes — where the Superadio Dynometer is on the job. This meter is direct reading. Measures the amplification factor, plate impedance, and mutual conductance of any radio tube. Extremely easy to operate. Tests three tubes per minute. Special Model S-2 Amplifier $30. Jobbers and Dealers Write for details on the Dynometer, and our liberal selling proposition. Be the first in your town to sell TESTED tubes. Superadio Dynometer equipped with phones and plug. Price $120. (Patents Pending) De WITT -La FRANCE CO., Inc. 54 Washburn Ave., Cambridge, Massachusetts Boston Representative: Chicago Representative: Martin, Hartley & Dewitt Sales Co., 99 Bedford St. William A. Welty & Co., 36 So. State St. This is a good lime to subscribe for RADIO BROADCAST Through your dealer or direct, by the year only $4.00 DOUBLEDAY, PAGE & CO. GARDEN CITY, NEW YORK Mexican Crystals "The Catwhisker's Delight" The BEST, bar none. For Crystal sets, "Silver Galena."' For Reflex sets, "Placerite." Once tried, always used. a 40c Each, 3 for $1.00 ^ Special for DeForest, 50c 70,000 users. You are next. Dtalers write H. D. HATFIELD & SON 1762 Vermont Ave. Hollywood California BROADCAST CONTROL OPERATORS who read Carl Drehers's discussion in the September Radio Broadcast on "Microphone Placing in Studios," should not miss "Additional Notes on Microphone Placing" to be printed in the January magazine. Weste57Kttdio%S! 134-136.WInnkeSt.Cliicogo.Ill. if Tested and approved by Radio BROADCAST ~if charged listeners-in which will be the equivalent of nearly five dollars. At the present time my company is running the broadcasting stations in this city and local companies are doing the same in the other towns, but that will cease of course when the new Broadcasting Company (now in course of formation) is ready. The reception of American stations here is achieved nightly using only single "valve" sets, and loud speaker volume using one stage of radio, detector and two of audio. I have heard kgo, kpo, kfi, and others using a Kennedy Model XV Receiver and have logged any number of "Yanks" on a low loss set of my own construction. I am at the present time building a Radio Broadcast Phonograph receiver as described in your paper. I expect great results from it and no doubt you will be pleased to hear how I get on with it. This quarter of the globe is excellent for reception as is evident by the long distance records made by New Zealanders. At the time of writing we are expecting the arrival of the American Fleet here and I have already heard their "sigs." from Lieutenant Schnell's short wave set. The "star" on your advertisements means a lot to us here in New Zealand. We cannot tell what is the latest apparatus and whether all the goods one sees advertised are what they are supposed to be, but in buying for this firm I have never once fallen in when guided by the "star." We have up to the present only handled small quantities of goods but we anticipate an increased volume of business this year. Thordarson, Belden, Na-ald, Peerless, Daven, Bell, Walnart, and Federal are amongst the lines we handle and we are satisfied that they are the best. So you can see what a valuable guide your paper is to us who "have no mother to guide us", as it were. We all enjoy your column "As The Broadcaster Sees It" — it is a scream. Wishing you all the success you deserve with your excellent paper. Very truly, yours, R. J. Haggett Wellington, New Zealand. The O'Connor Frequency-Changer THE O'Connor Frequency-Changer, which was described fully in the J une and August, 1925, Radio Broadcast, has caused much comment, and we have received numerous letters from readers who have had success with this circuit. By its use it is possible to convert any existing receiver to a super-heterodyne, and thus increase range and selectivity. Used in combination with a neutrodyne receiver it is possible to efficiently reduce the number of tuning controls to two, instead of the usual three. Here is a letter from an enthusiastic constructor. Editor, Radio Broadcast Doubleday, Page & Company, Garden City, New York. Sir: I have read with interest the controversy relative to the O'Connor Frequency-Changer, and as to its being a dud I can give evidence to the contrary. 1 have one of the first ones made in this territory and what it did to my five-tube neutrodyne is more than satisfying, in selectivity and volume and distance, and 1 had what was considered an exceptional set before. Atlantic City, Elgin, Providence, and Pittsburg come in between two degrees on the dial, and with no interference. Detroit and Toronto come in within half a degree on the dial, also with no interference. 1 am getting Fort Worth nightly now, and practically all stations above 500 watts in power. Very truly, yours, C. F. Rodgers, Conneaut. Ohio.