| 摘要 |
PURPOSE:To attain the positioning of a head to a reference track with high accuracy by using a position detector to decide the position of the head to the reference track and then applying the servo control to perform the positioning of the head to the reference track. CONSTITUTION:When a power supply is applied, an MPU 14 resets an internal track counter and sends a positioning mechanism 16 toward the outer circumference of a servo pattern until a position detector 17 is actuated with no servo control applied. When the detector 17 detects a reference track, the reproduction output of a magnetic head 9 is sent to a data processor via a head amplifier 10. At the same time, the start timing for servo action is sent to the MPU 14 through a synchronizing signal detecting circuit 11. The MPU 14 receives error signals from servo tracks 1 and 2 via a peak holding circuit 12 and an A/D converter 13 according to a servo pattern. Then the MPU 14 moves a position control motor 15 and holds the head 9 on a track. |
