| 摘要 |
PURPOSE:To eliminate the need for a compensation circuit for waveform distortion by supplying as a reference signal a video signal, obtained by demodulating part of a transmission output, to the control circuit for a transversal waveform equalizer. CONSTITUTION:A signal received by receiving antenna 9 is separated into sound and video signal components by input filter 10, frequency converter 11 and sound- picture separator circuit 12. The video signal, after passing thorugh demodulator 13, transversal waveform equalizer 14 and modulator 15, is mixed with the sound signal by synthesizer circuit 16. Further, the composite signal is supplied to transmitting antenna 21 by way of frequency converter 17, power amplifier 18, output filer 19, and directional coupler 20. Then, part of the output of directional coupler 20 is demodulated by demodulator 22 into a video signal with a sound trap, which is supplied to control circuit 23. Control circuit 23 compares a fixed waveform in the video signal with a previously-fored waveform and then controls transversal waveform equalizer 14 according to the comparison result, thereby eliminating a ghost and waveform distortion. |
