| 摘要 |
PURPOSE:To extract reproduced data without malfunction by sampling satisfactorily data even when the data is in want of periodical synchronizing signals. CONSTITUTION:A horizontal synchronizing signal separated in a horizontal synchronizing separator circuit 8 is made to have a pulse (b) of a width T by a monostable multivibrator 50. The pulse of the width T is delayed by (1H+tau) by a delay circuit 52, and pseudo horizontal synchronizing signal (c) is obtained. A phase comparator circuit 10 compares rising edge timing of a correction horizontal synchronizing signal (d) with that of an output signal of a divider 18, and obtains outputs (f) in accordance with the time difference of these signals. Thus the device is constituted so that a psuedo horizontal synchronizing signal after approximately tau period has expired can be used for the part being short of horizontal synchronizing signals; therefore a PLL will not be disturbed substantially. Consequently sampling errors due to a lack of horizontal synchronizing signals can be prevented.
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