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Pioneer radio station 2XG, also known as the "Highbridge station", was an experimental station located in New York City and licensed to the DeForest Radio Telephone and Telegraph Company. It was the first station to use a vacuum-tube transmitter to make radio broadcasts on a regular schedule,〔From 1912 to 1917 Charles Herrold made regular broadcasts, but used an arc-transmitter. He would switch to a vacuum-tube transmitter when he restarted broadcasting activities in 1921.〕 and, on November 7, 1916, was the first to broadcast U.S. presidential election returns by spoken audio instead of Morse code.〔Examples of election results sent in Morse code for the 1912 Presidential election include "Harvard Wireless Club Gets Returns" (''Boston Post'', November 6, 1912, page 3, broadcast by the Charleston, Massachusetts Navy Yard station) and "News Was Spread All Over Pacific" (''Waterloo Times Tribune'', November 7, 1912, page 2, broadcast by the Navy's Mare Island, California station).〕 ==Pre-World War I history== Initially all radio transmissions used spark transmitters, which could only transmit Morse code messages. In 1904, Valdemar Poulsen invented an "arc-transmitter" capable of transmitting full audio, and in late 1906 Lee DeForest founded the De Forest Radio Telephone Company and began producing his own "sparkless" arc-transmitters. Between 1907 and 1910 DeForest made a number of demonstration entertainment broadcasts, and even spoke about developing news and entertainment broadcasting stations, but did not establish a regular service at this time.〔"Wireless 'Phone Transmits Music", ''New York Herald'', March 7, 1907, page 8.〕〔"Wireless Telephony by the De Forest System" by Herbert T. Wade, ''The American Monthly Review of Reviews'', June, 1907, pages 681-685: "the inventor believes that by using four different forms of wave as many classes of music can be sent out as desired by the different subscribers".〕〔"Grand Opera by Wireless", ''Telephony'', March 5, 1910, pages 293-294.〕〔"Radio Telephone Experiments", ''Modern Electrics'', May, 1910, page 63.〕 In 1914, DeForest's Radio Telephone and Telegraph Company established a laboratory at 1391 Sedgewick Avenue in the Highbridge section of the Bronx in New York City. Vacuum-tube transmitters had recently been developed, which were found to be superior to arc-transmitters for audio transmissions,〔''Father of Radio: The Autobiography of Lee de Forest'', 1950, page 243. DeForest noted that he had been "totally unaware of the fact that in the little audion tube, which I was then using only as a radio detector, lay dormant the principle of ''oscillation'' which, had I but realized it, would have caused me to unceremoniously dump into the ash can all of the fine arc mechanisms which I had ever constructed..."〕 and the company now concentrated on developing vacuum-tube equipment, including "Oscillion" transmitter tubes.〔''Ibid.'', page 332.〕 In the summer of 1915, the company received an Experimental license〔"Special Land Stations", ''Radio Service Bulletin'', July, 1915, page 3.〕 for station 2XG, located at the Highbridge laboratory.〔The "2" in 2XG's callsign indicated that the station was located in the 2nd Radio Inspection district, while the "X" signified that it held an Experimental license.〕 DeForest had not made any broadcasting demonstrations since 1910, however, he decided to showcase the capabilities of the new vacuum-tube transmitters by introducing regular broadcasts of concerts and news bulletins. There were no formal government regulations restricting broadcasting at this time, so the company was free to transmit these programs over 2XG. Arrangements were made with the Columbia Gramophone record company to broadcast phonograph records from their offices at 102 West 38th Street in New York City—the phonograph company supplied records in exchange for "announcing the title and 'Columbia Gramophone Company' with each playing".〔De Forest, page 337.〕 The debut program was aired on October 26, 1916,〔"Columbia Used to Demonstrate Wireless Telephone", ''The Music Trade Review'', November 4, 1916, page 52.〕 where it was announced that, beginning November 1, the "Highbridge Station" would transmit a nightly schedule of broadcasts featuring the Columbia recordings. The station's original audience was mostly amateur radio operators〔"DeForest Wireless Telephone", ''QST'', April, 1917, page 72.〕—Carl Dreher would later recall "The quality was quite good, and I used to listen to the station for hours at a time".〔''Sarnoff: An American Success'' by Carl Dreher, 1977, page 41.〕 Some of the programming was oriented for a more general audience. A highlight occurred on the night of the November 7, 1916 Wilson-Hughes presidential election, with the broadcasting of election returns that for the first time were in full audio instead of Morse code. This program consisted of bulletins supplied by the ''New York American'', interspersed with phonograph records.〔"Election Returns Flashed by Radio to 7,000 Amateurs", ''The Electrical Experimenter'', January, 1917, page 650.〕 Just before shutting down at 11:00 PM, the station announced that Charles Evans Hughes had won, however the next morning it was learned that late totals from California had tilted the election in Woodrow Wilson's favor. Another widely publicized program was a "radio dance" held by listeners being entertained in Morristown, New Jersey.〔"Dance to Wireless Music 40 Miles Off", ''New York Times'', December 31, 1916, page 4.〕 DeForest initially used these broadcasts to advertise "the products of the DeForest Radio Co., mostly the radio parts, with all the zeal of our catalogue and price list", until comments by Western Electric engineers caused him to eliminate the messages.〔De Forest, pages 337-338.〕 The broadcasts were suspended with the entry of the United States into World War One when, on April 6, 1917, all civilian radio stations were ordered shut down, and 2XG was silenced for the duration of the conflict. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Radio 2XG」の詳細全文を読む スポンサード リンク
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