| 摘要 |
<p>PURPOSE:To enable a reproducing head to perform normal tracking by generating a pseudo CTL signal from a time code signal even when a CTL signal cannot be read by clogging of a CTL head. CONSTITUTION:A signal (f) is made by delaying a sync.word detecting signal (e) obtained by inputting a CTL signal (d) into a sync.word detecting circuit 4 by a delay circuit 5 by a prescribed time. At this time, the CTL signal (d) and the signal (f) are set to coincide with each other in leading edge. Then, either of the signals (d) and (f) is given to a phase comparator circuit 3, and is compared with a leading edge of a phase reference signal (a) in phase, so that a phase error signal (g) is obtained in correspondence to a phase difference. Thus, the presence of the CTL signal is decided, and when the CTL signal is no, a changeover is automatically made to the pseudo CTL signal generated from the time code signal. By this method, the tracking of the reproducing head can normally be performed.</p> |
