| 摘要 |
<p>PURPOSE:To decrease the servo recovery time by closing a tracking servo when the synchronizing signal detection level of a track to be traced reaches a prescribed level or above so as to restore a tape feed speed command giving nearly the half speed of the normal reproducing speed to the normal speed. CONSTITUTION:When the synchronizing signal detection level reaches a prescribed level or below, a processing section 19 brings a tape speed command VCMD to nearly a half speed of the tape feeding speed at the normal reproduction, generates a switching signal CHS to make a switch 20 open the tracking servo loop and superimposes a prescribed offset voltage V0 on the voltage VCMD. Thus, the capstan motor is driven at the speed being nearly a half of the normal speed. When an address is traced at a track TB actually to a track TA to be traced while the servo is disabled at a time T1, a recognized track number is coincident with a number traced actually at the time T2 to apply the track servo. Then the processing section 19 allows the switch 20 to close the servo loop thereby bringing the tape speed command to the normal speed command.</p> |
