Finally, starting in 1894, Guglielmo Marconi began to pursue the idea of building a wireless telegraph system based on Hertz wave (radio). Marconi implements a patented system.In the early twentieth Century, the radio transmitted information of the radio system was a continuous code. Initial efforts to develop a system for amplitude modulation for sound and music have been demonstrated in the 1900 to the year of the year, but few have been successful in the years since the year of the year 1906. The accelerated development of World War I gave all radio communications, and in the vacuum tube era today, the first application to the address book. An important change in the development of electronic amplifiers is the testing of a broadcast from a professional device. After the war, commercial radio began in 1920s, becoming an important medium for quality entertainment and journalism.
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