| 摘要 |
<p>PURPOSE:To previously prevent the overflow or underflow of a RAM due to drop out, etc., on a tape occurring by controlling the feed speed of the tape by the output of a monitoring device which monitors the write address and readout address of the RAM. CONSTITUTION:The frequency fs of a sampling signal Ss when the drop out occurs is changed in pulse shape. The output Aw of a write address counter 42 generates the deviation of an address proportional to the area of a frequency noise in pulse shape shown in a hatched line part S2, and it is inverted by a coefficient multiplier 81, and is added on the output Ar of a readout address counter 62. The output of a full adder appears in a direction opposite to a hatched line part S1. A hatched line part S3 is sent to a control DAC 83, a synthesis circuit 76, a motor driving circuit 77, and a capstan motor 71, which varies the rotating speed of the motor. Therefore, the feed speed of the tape 1 can be changed. Thereby, the difference (Ar-Aw) of the value Aw of the write address counter 42 and the value Ar of the readout address counter 62 is converged to Amax/2.</p> |
