| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent a band limit malfunction at a high degree of modulation while maintaining immunity to interference. Ž<P>SOLUTION: This FM receiver is provided with: a second mixer 14 for converting an FM broadcasting signal into an intermediate frequency signal; an IF bandpath filter 15 connected to the latter part of the second mixer 14; an FM detector circuit 16 for detecting the intermediate frequency signal which has passed the bandpath filter; S meter circuits 22 and 23 for detecting a signal level of the FM broadcasting signal; and a control circuit 25 for controlling a passing band based on AC components superposed on an output signal of the S meter circuit 23 when the signal level of the FM broadcasting signal is small. The FM receiver is also provided with a load switching circuit 31 for changing a level value of the AC components to a direction in which the passing band of the IF bandpath filter 15 does not switch to a narrow band under a situation where disturbance waves do not exist, in response to a combination of the degree of modulation and the presence or absence of the disturbance waves. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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