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Heinrich Hertz detects and produces radio waves.
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First radio program of voice and music broadcast in the U.S. (by R.A. Fessenden)
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The cascade-tuning radio receiver and the heterodyne receiver are introduced.
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: Edwin Armstrong patents a radio receiver circuit with positive feedback. Part of the amplified high-frequency signal is fed back to the tuning circuit to enhance selectivity and sensitivity.
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FM radio is born, but only in mono.
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The UM decides it needs an FM station, and expresses a commitment to radio broadcasting.
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Television is born. FM is moved from its original home of 42-50 Mhz to 88-108 Mhz to make room for TV.
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Advertising is accepted on WCBN-AM.
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United States radio stations begin broadcasting in stereophonic sound.
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In Paris an experimental digital FM transmitter begins operation.