PURPOSE: To prevent a horizontal synchronizing part from being missed and the resulting horizontal displacement of a reproducing picture by lowering the center frequency of frequency modulation signal for the period corresponding to the horizontal synchronizing part of a composite image signal.
CONSTITUTION: A pulse which is kept high level only for the period before and after a leading-edge of a horizontal synchronizing signal of the composite image signal is supplied to a switch circuit S from a pulse generating circuit 9. The switch circuit S is turned on during the high level of the pulse, a capacitor C2 is connected, and the frequency characteristics are lowered. Therefore, if a pseudo- bit (q) exists on a bit at a part of the disc corresponding to the leading-edge part of the horizontal synchronizing signal, the level of the signal corresponding to that pseudo-bit (q) is lowered, which prevents the affect of the pseudo-bit (q).
YAMADA KAZUO
IBARAKI KOJI
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