ocr: RADIO WAVES MICROPHONE ANTENNA OSCILLATOR AMPLIFIER Ap)))))) - RADIO BEAM = - - - SOUND SIGNAL TRANSMITTER RADIO DETECIOR LOUDSPEAKER As sound signal can be sent through the air in the form of radio waves. The electrical signal from a microphone modulates a radio wave, produced by a device called an oscillator. When the resulting wave hits an antenna, it produces an electric current. A detector recovers the electric sound signal and a loudspeaker produces a copy of the original sound.
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