| 摘要 |
A synchronizing scheme for use in color video recording systems which employs two voltage controlled oscillators, the first being phase locked to the color burst of the incoming video signal in recording, but operating as a freerunning oscillator on playback, and the second being locked to the horizontal sync of the incoming video signal in recording and of the jitter-affected off-tape video signal in playback. The first oscillator, through the medium of frequency dividers, generates the color subcarrier and supplies the motor and servo references to the recorder, and the second oscillator serves as a clock for a sync generator producing a sync pattern. This sync pattern is used for controlling the impressing of fresh sync information on the video signal in recording, and the reinsertion of the color burst in the off-tape signal in playback, and also for providing the trisequential driving pulses required by the trisequential color processing circuitry. The sync pattern is also used to drive and synchronize an external video source, for example, a camera. |
