| 摘要 |
<p>PURPOSE:To reproduce an accurate control signal by switching at least one of an input resistor of an amplifier and a load resistor depending on a time corresponding to a specific position of a tape to converge the mean DC value of the reproducing signal in a shorter time. CONSTITUTION:A control circuit 8 outputs an output pulse S3 corresponding to a specific position on a tape by an output signal S2 and FG signal obtained from a pulse generator 7 and representing the running amount of the tape. The switches 12, 16 are turned on when the signal S3 is at H level and in this case, resistors 10, 11 and resistors 14, 15 are connected in parallel respectively. Thus, the mean DC value of the reproducing signal is converged rapidly according to the time constant when the switches 12, 16 are connected is set smaller than the time constant decided by the reproduced signal waveform and the tape lower limit speed, thereby reducing the period until the output signal S2 of the comparator 3 outputs again a pulse corresponding to a reproduced CTL signal.</p> |
