| 摘要 |
<p>PROBLEM TO BE SOLVED: To attain the accurate and elaborate servo control of a tape running at a super low speed without being affected by the external disturbance. SOLUTION: This controller consists of a capstan for driving the running of the tape, a means for detecting the tape speed by detecting the number of FGs from there, and a phase servo control means for receiving the control signal read out from the tape to be reproduced and controlling the servo of the capstan. Then the phase servo control means is furnished with a reference clock signal of a specific period, a phase reference signal of a specific pulse width synchronized with the reference clock signal, an LS reference clock signal of N times period as high as the reference clock signal, and an LS phase reference signal of a specific pulse width synchronized with the LS reference clock signal, and when the phase difference between a reference control signal (XCTL signal) of the phase servo and the LS phase reference signal is within a prescribed range in some one signal among reproduction control signals (PBCTL signals) at the time of tape reproduction, the feedback phase control is carried out with the unmultiplied phase reference signal to the PBCTL signal other than the XCTL signal subject to phase deviations within a prescribed value.</p> |
