STEREO SEPARATION CONTROL DEVICE FOR FM TUNER

摘要

PURPOSE:To facilitate a stereo separation control, by setting the subsignal demodulation gain larger than the main signal demodulation gain for an IC-formed stereo signal demodulating circuit. CONSTITUTION:A stereo demodulating circuit 66 is formed into an IC, and the main signal and subsignal demodulation gains are set at a certain value each only by the component element inside the IC. The subsignal demodulation gain is set larger than the main signal demodulation gain. The gain ratio is set so that the highest separation is obtained in case a stereo signal of a normal phase distribution is applied to the input of the circuit 66. The input signal is supplied to the circuit 66 after receiving a compensation of phase at a high band through a low pass filter 64. Thus the variance is reduced for the gain of a low-band signal.