| 摘要 |
PROBLEM TO BE SOLVED: To automatically correct a deviation from a desired reception frequency of an oscillation frequency of a local oscillation circuit even in the case of reception of a disturbance signal, in an FM radio receiver. SOLUTION: For example, an OSC 106 is oscillated as an oscillation frequency according to adjustment of a capacitor bank 107 and a varicap VR1. Then, a reception signal generated by a mixer 103 is converted to an IF signal by an IF circuit 104. In the case that a frequency of the IF signal cannot be obtained at this time, an oscillation frequency of the OSC 106 artificially measured by a counter circuit 110 is compared with a standard value which is standardizes on the basis of an N value and a standard width setting value by an operation circuit 113 and is held in a standard value holding circuit 114, by a comparison circuit 115. When it is determined by a determination circuit 116, on the basis of the comparison result, that the oscillation frequency of the OSC 106 is not within a prescribed frequency range, a VR2 control circuit 117 finely adjusts a varicap VR2, in order to correct the deviation. COPYRIGHT: (C)2008,JPO&INPIT
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