| 摘要 |
<p>PURPOSE: To precisely and surely attain tracking control by reproducing a synchronizing signal having a specified digital signal and detecting the reproducing timing of the synchronizing signal for rotation of a drum. CONSTITUTION: A servo controller 10 controls a drum motor 4 so that a drum pulse signal DPG outputted for the rotational position of the drum 1 is synchronized with a servo reference signal 13. A regenerative signal 17a is outputted in a period when the signal 13 is an H to be supplied to a data reproducing circuit 20, and the circuit 20 outputs it to the controller 10 as reproducing level information 15. A low frequency signal strobe pulse 36 is generated at the timing when a reproducing head P0 passes through a dotted line A, and detects a regenerative signal level of a low frequency signal LS recorded on a track T1. When the head P0 is shifted in the direction of Z in a tracking state, a timing counter value 14 increases. The controller 10 controls the rotation of a capstan motor 5 so that the counter value 14 becomes the vicinity of the value corresponding to a tracking shift amount zero.</p> |
