| 摘要 |
PROBLEM TO BE SOLVED: To provide a noise canceller of a simple configuration that can sufficiently enhance a noise cancellation effect. SOLUTION: This invention provides a noise canceller that cancels television audio diversity noise generated when the antenna of a television audio multiplex receiver is switched. When it is detected that the electric field of a received radio wave outputted from a diversity signal generating circuit 24 is weak, a changeover circuit 22 selects an output from a delay element 21 obtained by delaying an audio intermediate frequency signal by a period being an integer multiple of a period of a horizontal synchronizing signal for a period of presence of diversity pulses to switch the antennas for a predetermined period in place of the audio intermediate frequency signal, and the output selected by the changeover circuit 22 is subjected to audio FM detection. As a result, the phase continuity is maintained to attain demodulation of an audio signal and discrimination of a stereophonic signal, and the noise caused in the antenna switching by the diversity pulse can be cancelled.
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