| 摘要 |
PURPOSE:To shorten a channel selection time at the time of presetting operation, etc., by allowing a 1st tuning circuit to tune to the nearly intermediate point frequency of the passing bend of an intermediate frequency filter and making a 2nd tuning tune to the intermediate frequency of a received signal. CONSTITUTION:The 1st tuning circuit 7 is used first to tune a broadcast signal to the nearly intermediate point of the passing band of the intermediate filter 4 and then the 2nd tuning circuit 8 is used to shift the tuning point from the nearly intermediate point of the passing band of the intermediate frequency filter 4 to the intermediate frequency, thereby tuning to the intermediate frequency completely. Consequently, when the tuning point is searched for first, the tuning point is easily detected because of the nearly intermediate point of the passing band of the intermediate frequency filter 4 and then the tuning point is only shifted to the intermediate frequency, so a tuner is made to easily tune to the broadcasting signal in a short time.
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