| 摘要 |
PROBLEM TO BE SOLVED: To reduce the cost and attain downsizing by decreasing the number of expensive SAW filters in a television receiver. SOLUTION: A trap circuit 7 is setup between a mixer 1 and a SAW filter 11. In receiving a television signal, a trap frequency is selected to be a video intermediate frequency of another channel adjacent to an upper frequency in an intermediate frequency band or its vicinity and to be an audio intermediate frequency of the other channel or its vicinity. In receiving an FM broadcast signal, the FM broadcast signal is frequency-converted into a chrominance subcarrier frequency in the intermediate frequency band or its vicinity and the trap frequency is selected to be nearly the middle between the video intermediate frequency and the chrominance subcarrier frequency in the intermediate frequency band and the video intermediate frequency in the intermediate frequency band or its vicinity, and the SAW filter 11 outputs a frequency-converted television signal or the FM broadcast signal.
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