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Raymond A. Litke (1920-1986) was an American electronic engineer, the inventor of a practical wireless microphone, and the first to patent the wireless microphone. He was born and raised on a farm near Alma, Kansas, but spent most of his adult life in San Jose, California. ==Wireless microphone== Litke invented a wireless microphone in 1957 while employed as an electronics expert at San Jose State College. His supervisor challenged him to invent a microphone to use in educational presentations which would be free of wires. Litke’s wireless mike resembled a silver tube with “a microphone at the top, a transmitter in the middle and its battery power supply at the bottom.”〔San Jose News. September 10, 1960〕 It was 6 inches long, 1 inch in diameter, and weighed 7 ounces; the device had a broadcast range of up to a half-mile. Two types of mikes were available: lavalier and hand-held. A companion receiver, weighing 17 pounds, completed the portable sound system.〔Alma Signal-Enterprise. November 10, 1960.〕 Although Litke prototyped the wireless microphone in 1957, he did not file for a patent until May 8, 1961. U.S. Patent No. 3,134,074 was officially granted on May 19, 1964. His microphone is sometimes also called the “Vega-Mike” after the Vega Electronics Corporation which first manufactured it as a product. Vega sold other electronics items and tapes developed by Litke.〔〔Alma Signal-Enterprise. February 26, 1981.〕 Litke's wireless microphone was first tested at the Olympic trials held at Stanford University in 1959.〔 Next, the American Broadcasting Company (ABC television) tested the microphone at the Democratic and Republican Conventions in 1960.〔San Jose Mercury News. September 10, 1960.〕 Candidates John F. Kennedy and Richard Nixon were among the first celebrities to use the Vega-Mike. TV anchor John Daly praised Litke's invention on the ABC television news broadcast in July 1960. Daly introduced it to Americans with the words: "This is a Vega-Mike" and went on to explain it "is a wireless microphone, six inches long... without any wires of any kind...." Daly pointed out it could be used to broadcast "within the (convention) hall or outside... without the inconvenience of interconnecting microphone cables...."〔〔ABC News. July 1960.〕 Even the Federal Communication Commission was impressed with it. The FCC gave him 12 frequencies instead of the one he was seeking.〔 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「Raymond A. Litke」の詳細全文を読む スポンサード リンク
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