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Radio Digest, 1924-1925

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Radio Digest, 1924-1925 B64714 6 DEC 271924 Aerial Aids for Christmas Set Buyers—J. E. Owen; New Het-duo-gen Circuit; "X" Wire—Key to Neutrodyne Success ; Details of $1,000.00 Gold Award Set Radio Di EVERY m= PROGRAMS TEN I CENTS REG. U. S. PAT. OFF. & DOM. OF CANADA \/,J YT Copyright 1924 VOl. -A.1 By Radio Digest Publishing Co. SATURDAY, DECEMBER 27, 1924 No. 12 NEW SET—FIND OF YEAR HET-DUO-GEN TUNES EITHER COAST EASILY Selectivity C. E. Brush Uses Six Tubes in Decidedly New Hook-Up —Tells How to Build Meet the Het-duo-gen! The set that really brings in what you want when you want it has come to light at last. A complete surprise be- cause its development is so different from the lines along which most ex- perimenters were known to be working. Combining the advantages of the hetero- dyne with regeneration on two tubes, C. E. Brush, of Chicago, has achieved a degree of selectivity that is almost miraculous. The sensitivity seems con- sistently to equal that of an eight tube PHONE CONNECTION super-heterodyne while the volume from three stages of audio frequency ampli- fication is more than enough for dancing. LONDON -NEW YORK A large loud speaker is required to handle it. Once the circuit is explained and the NEW STATION READY FOR operation understood, it all seems so simple that one wonders why it hasn't SERVICE NEXT YEAR been done before. Cost? The cost to (Continued on page 2) Will Use 4,000,000 Watts Power for Transoceanic Talking—Toll Charge Approximately $25 LONDON, Eng.—It is not only possible, but absolutely certain that in a year's time, any man in England can pick up the ordinary telephone in his house and speak to a friend in New York. This new scientific stride will be a great help to a number o f people, particularly business men who are making regular trips to Europe. Many trips will undoubtedly be saved. This will be possible when the long disance Radio station of the British post- office at Rugby is completed. Eight giant masts cover an area of 800 acres. Tower- ing 820 feet above the ground, each of the masts is in the form of a tripod and weighs 200 tons. Use 4,000,000 Watts Power The power plant will be the greatest of its kind in the world. Over 400, 10,000 watt tubes will be used for this service. They are built of fused copper and glass to permit their cooling by water. Thanks to Radio, the ordinary telephone subscriber will be able to communicate with any vessel in mid-ocean. This has been tried experimentally with wonderful success on boats crossing the English cha tinel. The station will be used to com- nlcate with Rocky Point, Long Island, and when it is completed, anyone in fland can telephone to anyone in New fork >ii a charge of about $25 for a llmll r of minutes. RADIO DIGES T—Illustrated December 27, 1924 TO FIND $10 00 GOLD AWARD SET! ENTHUSIASM ANSWERS CALL $1,000 GOLD AWARD SET CONTEST RULES This contest opens at once and built around dolls, finger rings, will close on Saturday, January hats, etc., will not be considered. 17, 1925, at midnight. All sets re- 8. Sets desired are those based on FOR BEST ORIGINAL HOOK-UP ceived up to that time will be an original circuit or part of cir- entered. cuit that functions better than The thousand dollars in gold circuits commonly in use. Orig- Radio Digest Contest, Open to All, Stirs Radiophan will be divided into the follow- inality is one of the prime con- ing prizes First, $500v 00; Second, siderations. $250.00; Third, $100.00; Fourth 9. Entrants who are not awarded Interest—Many Sets Already Entered—Speed to Ninth inclusive; $25.00 each. prizes, but whose sets are con- In the event of a tie, the full sidered worthy of constructional Necessary in Submitting Receivers. amount of the prize tied for, will description in Radio Digest, will be awarded to each tying con- be paid at regular manuscript testant. rates. once. It will not be held longer than With only seven days in which to Contest is open to all Radio- 10. Entrants must guarantee to absolutely necessary to make compari- their sets in since the announce- phans, whether or not subscrib- Radio Digest exclusive publica- send sons. ers to Radio Digest Illustrated. tion rights of all descriptions of ment last week of the Radio Digest Some of the most radical Radio im- A neatly drawn hook-up diagram their sets. The exclusive pub- $1,000.00 Gold Award Set contest, sev- provements have come from Radiophans and short description (200 words) lication rights will be in force of entries have already made who did not know what they had done, eral score of the salient features of the set for all sets winning or picked for but recognized the fact that they had their appearance at this office! should be enclosed in separate later description in Radio Digest. something better than ordinary. The surprise of all came when five letter advising set is being 11. Judges not interested in manu- Many important inventions in use to- sets were submitted on the day the shipped. Entrants do not need facturing will be selected by day were only accidents when first con- appearance to be authors or writers. Radio Digest to make the awards. December 20 issue made its ceived. Sets must be sent insured pre- The award of prizes will be based on the newsstands. Perhaps your set contains such an acci- paid express or insured parcel on: Selectivity, range, volume, Evidently the contest has taken the dent? post. All sets, including winners, quality of reproduction, simplic- Radiophans by storm. Everyone seems Perhaps out you have thought some- will be returned insured collect ity of operation, constructional interested and willing to co-operate with thing new in circuits? to entrants. feasibility, economy of construc- this publication to determine whose re- Judges to Be Announced Soon ceivers contain the most important con- Radio Digest is not to be held tion, minimum re-radiation, uni- Several world-renowned leaders and or loss versality, practicability. tribution to the Radio art. responsible for breakage Radio inventors have been invited to sit Radio clubs have written for particu- in transit. Pack sets carefully. 12. Ship sets and address corre- as judges in the Gold Award Set contest. Mark boxes and contents plainly spondence to the Gold Award Set lars. Their acceptances Newspapers have asked for more in- are being awaited. with name and address of sender. Editor, Radio Digest Illustrated, formation regarding the award. Every precaution is being taken to in- Tubes and batteries need not be 510 North Dearborn street, Chi- tubes are cago, 111. All controversies will Telegrams and letters direct to Radio sure the fair selection of the winners. sent unless matched essential to operation. be decided by the Gold Award Digest indicates that interest is booming The contest is on! Who will win the or novelty sets are not Set Editor, whose decision will in every section of the country. $1,000.00? Freak enclosed in or be final. Remember Shipping1 Instructions Only those who submit entries will be desired. Sets Emphasis must be placed on the manner taking advantage of this ' great oppor- to be used in shipping entries to Radio tunity. It may be the turning point in Telegraphic communication by Radio Digest. Read carefully rules 5 and 6 in someone's life. It may make a Radio NEW SET—FIND OF YEAR the list given on this page. manufacturer or inventor out of a man or established between Beirut, Syria, and (Continued from page 1) Careful packing may be the cause of woman who has never considered him or Belgrade, Jugo-Slavia, has recently been build is remarkably low, one set winning out over another, be- herself as even a cog in this rapidly pro- made available for commercial uses much lower than a "super." The 23-plate variable cause of damage incurred by the poorly gressing, but still infant, industry. through • an ordinance issued by the condenser and three good quality audio packed one. January 17 is the finishing line. Hurry! French high commissioner for Syria. Do not send novelty or freak sets built frequency transformers are the principal items in the list of parts. in miniature houses, dolls, finger rings, Controls are symmetrically arranged tie pins, etc. Read rules 7 to 8. on Remember that you need not know how the panel and het-duo-gen is attractive, as well to write articles in order to enter your as being the most efficient ever tested. Two het-duo-gens were tried out set. Ability as an author has no weight CONTENTS to be sure in awarding the prizes. Draw a hook-up that location had nothing to Radio Digest, Illustrated, Volume XI, Number 12, published Chicago, Illinois, December 27, 1924. Published it with short explana- do with the results. diagram, send a weekly by 'Radio Digest Publishing Company, 510 N. Dearborn Street, Chicago, Illinois. Subscription rates, yearly, tory letter to the Gold Award Set Editor, Five Dollars; Foreign Postage One Dollar additional; single copies Ten Cents. Entered as second class matter Goes Through Locals pack your set entry carefully and send at the postoffice at Chicago, Illinois, under the Act of March 3, 1879. Located within a mile of two of Chi- it separately prepaid, insured, to the Gold cago's most powerful northside broad- Award Set Editor, Radio Digest, 510 N.
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