| 摘要 |
<p>PURPOSE:To eliminate the disturbance of a reproduced screen during the operation to find the tracking optimal point by changing an equalizer characteristic between a period in which a tracking phase is shifted and a period after the fixation of the tracking period. CONSTITUTION:While a control circuit 25 finds the optimal tracking position by shifting the tracking phase, since it compensate the characteristic of an FM-modulated regenerative signal with the use of an equalizer circuit 16B, even when the level of the regenerative signal is decreased during the period, a reverse phenomenon is hardly generated, and the safe reproduced screen without the disturbance can be obtained even during the tracking control until the discovery of the optimal point. In addition, after the optimal tracking phase is discovered, since the characteristic of the regenerative signal is compensated by using an equalizer circuit 16A at a characteristic to improve the frequency characteristic of a video signal after demodulation, the quality of the normal screen is not damaged. Thus the disturbance of the reproduced screen during the operation to find the tracking optimal point can be eliminated.</p> |
