| 摘要 |
PURPOSE:To obtain a reproducing state similar to the state at normal operation by making the time axis of an output of a variable delay line at the special reproduction discontinuous for a period corresponding to a 1/2-wavelength of a chrominance subcarrier so as to prevent a new time error. CONSTITUTION:An NTSC signal including the time error is introduced to a variable delay line 2 at the normal reproducing state and a burst is extracted at an output terminal 7. The burst is compared with a reference frequency 12 so as to detect a time axis error and the delay time of the variable delay line is controlled by a frequency proportional to its detected voltage to eliminate the time axis error of the video signal appearing at the output terminal 7. Then, in reproducing a video signal one frame before or after while being skipped, the output of the variable delay line is made discontinuous by the output of a trigger FF for a period corresponding to the 1/2-wavelength of the chrominance subcarrier. Thus, the chrominance subcarrier is continuous as a result and no distortion is generated within the delay circuit, allowing to operate the circuit as if the operation were the normal operation. |
