| 摘要 |
PURPOSE:To enhance the S to N ratio as well as lower the distortion by giving the switching to the stereo composite signal in synchronization with the subcarrier and thus extracting the signal with suppression of the signal component including the information of the unnecessary channel. CONSTITUTION:The switching operation is given to stereo composite signal IN in synchronization with subcarrier 5, and the switching amplification is carried out via switching circuits 6L and 6R the gains of which change alternately. Thus the output is extracted with suppression of the signal component including the unnecessary channel information to the signal component including the necessary channel information. Base on this extracted output, operation 10L is given to the suppressed stereo composite signal to negate the signal component including the unnecessary channel information. Thus the signal component including the necessary channel information is extracted. |
