| 摘要 |
PURPOSE:To execute the tracking without fail by measuring the head shifting quantity from the counting of a driving pulse to a stepping motor and discriminating whether or not the measuring shifting quantity is in the prescribed range with the track center as a reference when a designating track is ideally recorded. CONSTITUTION:From a CPU 7 to a step motor driving circuit 8, a driving pulse P2 is supplied, a step motor driving circuit 8 to receive the driving pulse P2 drives a four-phase stepping motor 3 with a two-phase exciting system and a reproducing head 2 is shifted only by 8.3mu per pulse through the head feeding mechanism not shown in the figure. In the CPU 7, a counter 9 to count the driving pulse P2 and measure a head shifting quantity is built. When the inversion of the head shifting is repeated two times, in which the previous and present level difference is reference level difference DELTAV or above, after the peak decision is executed once, the tracking is completed after the reproducing head is returned to the position which comes to be the maximum level.
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