| 摘要 |
PURPOSE: To obtain the same bit length, so far as the recording frequency and the recording time length are equal, regardless of the recording and recording positions by making a channel clock variable corresponding to the recording and reproducing positions. CONSTITUTION: As the result of operation by an operating circuit 15, a frequency dividing ratio is set by a frequency-dividing ratio circuit 21. The frequency dividing ratio is set so that the ratio is larger on the inner surface and smaller on the outer surface. The value 1/N at the frequency-dividing ratio circuit 2 becomes the frequency of 1/N at a circuit 22. The clock at 1/N and the clock from an oscillator are inputted to a phase comparator 17. The output of the phase comparison is inputted to a VCC circuit 19 after passing a loop filter 18. The frequency dividing ratio of the clock signal of N times is changed by the recording position of a recording mechanism system to an original glass board. So far as the inner and outer frequencies are equal, the same bit length can be obtained. |
