| 摘要 |
An intermediate frequency input circuit is connected between output ends of a frequency mixing circuit and input ends of an intermediate frequency amplifier circuit. The intermediate frequency input circuit includes a pair of input ends (11,12): a pair of output ends (11,14); parallel resonance circuit (4,5), which is connected between the pair of input ends, resonating with an intermediate frequency of a selected channel; a series circuit, which is connected between one of the pair of input ends and one of the pair of output ends, including a first trap circuit (6,7) for trapping an intermediate frequency component of an upper adjacent channel and a first resistor (11); a series circuit, which is connected between the other of the pair of input ends and the other of the pair of output ends-, including a second trap circuit (8,9) for trapping an intermediate frequency component of a lower adjacent channel and a second resistor (13); and a parallel circuit, which is connected between the pair of output ends, including a third resistor (14) and a capacitor (15). <IMAGE> |
