| 摘要 |
PURPOSE:To surely remove a crosstalk by obtaining the time difference of neighboring synchronizing signal on an adjacent track to a certain synchronizing signal at every one rotation of a disk, and supplying a reproducing video signal from the reproducing synchronizing signals through a notch filter to a demodulation circuit only for a constant time when this time difference passes. CONSTITUTION:After the time TH and (tH-TH) from the time when a horizontal synchronizing pulse is generated, during the constant period tauH, or after Tv and (tv-Tv)from the time when a veatical synchronizing pulse is generated, during the constant period EtV, a selection switch 5 is switched to the notch filter 6 side. The reproducing video signal is supplied to the demodulation circuit through the notch filter 6 and the horizontal and the vertical synchronizing pulses on the adjacent track are prevented from passing. Thereby, the crosstalk of these synchronizing pulses can be effectively removed, since during the reproduction of the horizontal and the vertical synchronizing pulse, the selection switch 5 is not switched by the operation of an AND gate 31, a reproducing operation is normally performed.
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