| 摘要 |
PURPOSE:To normally obtain right and left stereo outputs whether an FM demodulation characteristic in a tuner is a normal S-curve characteristic or an inverse one by switching the inversion or non-inversion of a demodulation sub-signal or a demodulation main signal in accordance with the demodulation polarity of the FM demodulation circuit of a main signal. CONSTITUTION:An FM stereo signal received by a tuner 11 is demodulated by an FM demodulator 131 inside the tuner and inputted to an FM stereo processing circuit 12. When the tuner receives a sound multiplex signal, one demodulation sub-signal SUB output is supplied directly to one input terminal (a) of a switch SW1 and supplied to the other input terminal (b) of the switch SW1 through an inverting circuit 132. The other demodulation sub-signal SUB output is also supplied directly to one input terminal (b) of a switch SW2 and supplied to the other input terminal (a) of the switch SW2 through an inverting circuit 133. Thus, whether the FM demodulation characteristic in the tuner is the normal S-curve characteristic or the inversion one, the right and left stereo outputs can be normally obtained. |
