The first sound transmitted via a wireless or radio device is an unclear, often disjointed voice. Therefore the sound or music can not be transmitted over the radio. In 1903 Reginald Fessenden, an American, was able to transmit his voice on radio to a recipient a mile away. His voice was difficult to catch, because the electric magnetic waves that took him moved too fast.
In 1904 an Englishman named sir John Flemming invented the vacuum tube (empty). This tube is able to monitor the speed of radio waves. With this the sound becomes clearer. Then in 1906 Lee De Forest invented a radio tube called triode. With this tool it is possible to raise the sound.
In 1915 began sending voice via radio from Washington to Honolulu and Paris. The first radio station to deliver music to listeners located in Pennsylvania, Pittsburgh. The black record is sounded and the sound is transmitted over the radio. It happened in 1920. Now everywhere in the world we hear various sounds from the radio. In fact, young people are good at making their own radio. They set up an amateur radio.
Sumber: Kitab Emas"Penemuan-penemuan Dulu sampai Sekarang"
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