| 摘要 |
A receiver has an amplifier for amplifying a TV broadcast signal. A mixer mixes the amplified signal with an oscillation signal corresponding to a channel selection signal and generates a low frequency signal. A bandpass filter generates a signal having an amplitude corresponding to the low frequency signal. Electric field intensity filtering circuits filter the low frequency signal. A subtractor calculates a difference between the output from the filtering circuits and the output from the bandpass filter to generate a difference signal which is negatively fed back signal to the amplifier when an amplitude of the difference signal is larger than a predetermined value. The signal from the filtering circuit is the negative feed back signal when the amplitude of the difference signal is not larger than the predetermined value. An AGC signal corresponding to an electric field intensity of the output from the mixer is inputted to the amplifier.
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