| 摘要 |
<p>PURPOSE:To execute tracking by generating a tracking error signal which can realize an off-track in a prescribed quantity by only one part, even if a tracking signal of one channel is omitted due to blinding of a head, etc. CONSTITUTION:At the time of a regular reproduction, a switching circuit 30 is set to an L side, and an output 22 of a first sample holding circuit 16a is inputted to a second sample holding circuit 16b through a differential amplifier 17. In such a case, a selector circuit 31 selects a second sampling pulse SP2, and the circuit 16b outputs a tracking error signal 24. At the time of after- recording, the switching circuit 30 goes to an H side, and an output 22a of an amplifier 29 is inputted to the circuit 16b through the amplifier 17. In such a case, the selector circuit 31 selects 9 third sampling pulse SP3, and the circuit 16b generates a tracking error signal 24d. In such a way, even if a tracking signal of one channel is omitted, tracking can be executed.</p> |
