| 摘要 |
PURPOSE:To increase the audio quality of television audio, by enabling to switch the system into an intercarrier system at the channel switching, in a receiver with an audio demodultion circuit of the intercarrier system and split carrier system. CONSTITUTION:A mute pulse generated from a channel selection circuit 2' at channel switching is applied to a trigger terminal of a monostable multivibrator 49, the output is applied to amplifiers 27, 33 through an OR gate 42, the output signal of the amplifier 27 is muted and the circuit is switched to a demodulation circuit 30 of intercarrier system compulsively. Thus, an transient state of channel selection, shock sound generated when the response speed of a frequency discrimintion circuit 26 and a comparison circuit 41 is not quick can be eliminated. |
