| 摘要 |
PURPOSE:To obtain a reference signal which has a frequency equal to the burst frequency and has a phase shift quantity set to a prescribed value, by sending an input phase information signal to a phase shifting circuit after making the frequency lower than the reference signal and shifting the phase. CONSTITUTION:A reference video signal REF-V applied to a terminal 4 is supplied to a synchronizing signal separating circuit 32, and a horizontal synchronizing pulse PH is separated, and a gate pulse signal PG is formed by pulse formation in a circuit 33. A burst signal separating circuit 34 is controlled by this signal PG, and a burst signal SB is supplied to a phase comparator 25. Meanwhile, the signal of an oscillation frequency 4fsc of a voltage control oscillator VCO21 of a phase lock loop 30 is divided in frequency dividers 22 and 35, and a signal SA of a frequency fsc/2 is sent to a phase shifting circuit 36 and has the phase shifted by a monostable multivibrator signal 36a. An output SE is sent to the comparator 25 as a signal SD by a gate circuit 37 when the gate pulse PG functions, and this signal SD is compared in phase with the burst signal SB. |
