| 摘要 |
PROBLEM TO BE SOLVED: To obtain an FM radio receiver for improving receiving quality by preventing the influence of a frequency of an adjacent station which can disturb a receiving frequency. SOLUTION: The FM radio receiver is provided with a control circuit 13 for shifting a local oscillation frequency when the level of a sound signal obtained by demodulating an intermediate frequency signal obtained by converting the frequency of a received radio wave to be output is not higher than a prescribed level and switching a selected desired frequency to a prescribed frequency, a circuit 12 for detecting electric field strength of the switched prescribed frequency, a counter 11 for counting IF count values of the intermediate frequency signal when the detected electric field strength is equal to and greater than the prescribed level, and an AGC control part 10 for adjusting the gains of a frequency converting part 3 and an intermediate frequency amplifier 7 on the basis of an output of the control circuit 13, returns the switched prescribed frequency to the selected desired frequency, selects a narrow-band pass filter 5b and lowers the gain of the AGC control part 10 when the IF count value is within a prescribed range from the prescribed frequency. COPYRIGHT: (C)2007,JPO&INPIT
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