| 摘要 |
PURPOSE:To execute a tracking control exactly, by sample-holding an envelope detection signal of a reproducing FM signal, making its output pass through an A/D converter, and executing a prescribed operation processing. CONSTITUTION:A signal reproduced from video signal 3a, 3b is inputted to a sample holding circuit 8 through a preamplifier 5, a BPF 6 and an envelope detecting circuit 7. The signal sampled at every horizontal synchronizing signal is inputted to a microcomputer 10 through an A/D converter 9. On the other hand, a signal from a pulse generator 11 is supplied to a reset terminal of a counter 13 whenever the video heads 3a, 3b track a recording track, and its output is inputted to the microcomputer 10. Subsequently, a head position data is supplied to bimorph elements 2a, 2b through a D/A converter 17 and a driving circuit 18. In this way, the tracking control is executed exactly. |
