| 摘要 |
PROBLEM TO BE SOLVED: To save power consumption during constant standby reception, to suppress the generation of local spurious interference, to simplify a shield structure, and to make this device compact and light in weight by adopting a single conversion system. SOLUTION: A down-stream signal from a CATV input terminal 11 is switched through a high-pass filter 100 to UHF band, VHF HIGH band, and VHF LOW band circuits by input selecting circuits 101, 102, and 103. For example, at the time of the UHF band channel reception, the UHF band system from the input selecting circuit 101 to a mixing circuit 113 is operated, while other systems are not operated. The UHF band signal is tuned for respective channel by a high frequency amplification input synchronizing circuit 104 and amplified, and a received signal is derived by a high frequency amplification output circuit 110 and converted into an intermediate frequency signal by a mixing circuit 113. Also, frequencies higher by intermediate frequencies of 44 MHz is supplied to each band local oscillation circuit 116, 117, and 118.
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