| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to read tape information even though a servo lock is disengaged during a high speed running by controlling a relative speed between a magnetic tape and a rotation drum. SOLUTION: When a tape speed is a certain double speed in tape running, the fluctuation of the tape speed is monitored (S001); and if the tape speed decreases beyond an allowable range where data playback is considered possible, then a control is performed to lower the relative speed reference in response to the decrease in tape speed (S002). Here, the relative speed reference is lowered, that is, tape speed reference information and drum number of revolutions reference information are lowered and the relative speed between the magnetic tape and rotating drum can be kept almost constant. |
