| 摘要 |
<p>PURPOSE:To prevent a positioning signal from misdetection at the time of overwriting and to reduce tracking variation by suppressing the positioning signal recorded before being generated on a pilot signal reproducing position in a scanning track by a gate signal at the time of overwriting. CONSTITUTION:An output (RF signal) SR from a switching circuit 27 is supplied to a band pass filter 70 to be a filtering means, an output from the filter 70, i.e. a positioning signal or a PCM signal, is supplied to an envelope detecting circuit 71 to detect an envelope and an output from the circuit 71 is supplied to a comparator 72 to compare the signal with a reference value and to form a gate signal. The gate signal suppresses a positioning signal generated on a pilot signal reproducing position in a scanning track at the time of overwriting. Consequently, the positioning signal can be prevented from misdetection at the time of overwriting and the tracking variation can be reduced.</p> |
