| 摘要 |
PURPOSE:To ensure the proper switching between the stereo-monaural reproduction through a simple constitution and thus to secure good S/N at all times by turning on the stereo-monaural switch circuit when the levels of the pilot signal and the IF signal are more than the prescribed levels respectively. CONSTITUTION:Stereo-monaural switch circuit 22 is inserted between subcarrier signal generator circuit 24 and stereo demodulator circuit 40 and then supplies the output of pilot signal detector circuit 29 and rectifier circuit 30 supplied with the IF signal to circuit 22 in the form of the control signal. And circuit 22 is turned on only when the levels of the pilot signal and the IF signal are more than the prescribed levels respectively. In this way, the intensity of the received wave can be detected assuredly through a simple constitution. Accordingly, the proper switching is ensured between the stereo and monaural reproduction with good S/N. |
