| 摘要 |
PURPOSE:To avoid the effect of an AM intermediate frequency amplifier at FM reception by applying a bias voltage to an AGC voltage for AM at FM reception to reduce the gain of the AM intermediate frequency amplifier. CONSTITUTION:A voltage of a variable resistor 64 is fed to a switch circuit 32 at AM reception to apply muting at AM reception. On the other hand, a switch 36 is changed over to the position of a contact F at FM reception to constitute a power supply 73, this voltage is fed to a mixer circuit 42 and an intermediate frequency amplifier 46 as an AGC voltage and the gain is reduced. Thus, the muting at FM reception is applied. |
