| 摘要 |
<p>PURPOSE:To prevent capstan servo from getting disorder by supplying no signals to the capstan servo at a time when the variation in the level difference between crosstalk due to the pilot signals of both neighboring tracks is large. CONSTITUTION:When the tracking is stable i.e. Q output of an FF D11 is at an L-level, an AND gate D14 turns off. At this time, if the level difference between the crosstalks due to the pilot signals of the both neighboring tracks is double or three times of the level of an ATF error signal, an AND gate D13 turns off even though a pilot signal for on-tracking is correctly detected because the output of a comparator A10 comes to an L-level. Therefore, a sample pulse GP1 outputted from a controller and timing generator D8 is not impressed to an S/H circuit A11, hence, at the same time, a track shifting length is not outputted to the capstan servo as an ATF error signal. This means that the disorder of the capstan servo because of the interference of a pilot signal remaining after erasing due to an over write, can be prevented.</p> |
