| 摘要 |
PURPOSE:To reproduce sound signals of high quality through an inter-carrier system by removing an amplitude modulating component and a frequency modulating component included in a video signal. CONSTITUTION:Video intermediate frequency (VIF) obtained from a VIF circuit is divided into 1/10-1/100 frequency by limiter and dividing operations of a divider circuit 14. At that time, both amplitude and phase modulating components included in a video component are reduced. An output from the circuit 14 drives a synchronous generator 15, which generates a signal synchronizing with the output frequency of a tuner 12 and including no amplitude modulating and phase modulating components. The output of the generator 15 is mixed with the output of a sound IF amplifier circuit 16 by a mixer 17 to be converted into the 2nd intermediate frequency, which is demodulated by a demodulator 18, obtaining the sound signals of high quality including no noise. |
