| 摘要 |
PURPOSE:To reduce the tacking time while decreasing the number of times of head movement by detecting the signal at the position in the vicinity of an objective track before an instructed objective track position signals are detected and positioning the head based on the detection output. CONSTITUTION:An automatic tracking circuit 20 applies position control via an amplifier 22 and a head mobile mechanism 15 so that the magnetic head 8 is placed at a position where the reproduced RF signal of a preamplifier 16 is maximized. When the objective track midposition is B and adjacent points before and after one step are A, C, with a signal at the position B maximum, the head is moved in the order of A C B or C A B. If the position B does not show a maximum value, the discrimination forwarding the head to a larger point among A and C by 3d and reversing the head by 1d is repeated. Thus, the number of times of the movement of the head 8 is decreased to reduce the tracking time.
|
