| 摘要 |
PURPOSE:To eliminate the need for manual adjustment by discriminating a phase difference of a subcarrier of a reproducing signal to a phase of the subcarrier of a video signal for driving a VTR main body to cancel drift and jitter. CONSTITUTION:The 2nd switcher 6 changes over alternately a driving video signal 33 and a reproducing signal 39 of the VTR main body at each horizontal period by a gate signal 38 and outputs a video signal 40. A chrominance component is extracted from the video signal 40 by a high-pass filter 7 and a horizontal synchronizing signal 42 is formed by the 2nd synchronizing separator circuit 9. A phase comparator 12 samples the color burst of a chrominance signal 41 formed into a pulse and compares the phase to control a gate signal 43 to be positioned at the center of the waveform of the color burst. The phase of the color frame is controlled by an integration signal of the gate signal. |
