| 摘要 |
<p>PURPOSE:To make a head trace accurately in the middle of a track and to improve the playability by providing a subtractor for obtaining a difference between two sample circuits in their output signals to be a tracking error output. CONSTITUTION:The subject device possesses a switch circuit 101 capable of being turned on only during a reference pulse outputted by a reference signal generator 10, and is otherwise connected to a ground 12. The outputs of the heads 1a and 1b are inputted to synchronous signal detecting circuit 8, where two sample pulses in total are generated at the time of detecting a synchronous signal on a track by the synchronous signal detecting circuit 8 and after delaying it by a given period of time by a timing circuit 9. On the other hand, a tracking signal which is proportional to a crosstalk quantity with both adjacent tracks of the reproducing head is selectively detected out of the output signal of the heads 1a and 1b by a detection circuit 11. An output of this detection circuit 11 is sample-held by sample circuits 61 and 62 using the two sample pulses, and their difference is obtained by the subtractor 63 to be a tracking error signal (e). In such a manner, the recorded track can be traced on average in the middle by the head.</p> |
