| 摘要 |
PURPOSE:To prevent the pitching of a picture, by taking out specific head switching pulses different in V sink position in the tape moving section and by changing the delay time of a pseudo V pulse delay circuit by these pulses. CONSTITUTION:A signal indicating the rotation phase of a rotary head cylinder 1 is applied to an FF2 for head switching to generate a head switching pulse (b). This pulse (b) is delayed by a monostable multivibrator 13 for pseudo V sink where the delay time is varied, and the delay pulse is mixed as a pseudo V sink with a reproduced video signal by a mixing circuit 14. Pulses are extracted from pulses (b) in the order predetermined in an output time (a) of a motor driving memory 5 by a frequency division processing circuit 15. That is, the second pulse (c) and the third pulse (d) are extracted and are applied to the monostable multivibrator 13 for pseudo V sink, and in this time, the delay time of the monostable multivibrator 13 for pseudo V sink is changed by the time variation of the reproducing V sink. |
