| 摘要 |
<p>PURPOSE:To regenerate a video signal while synchronizing completely with an audio signal by changing the frequency of a control signal for deciding the number of revolution of a drum by using frequency comparison based on the time information of a digital audio signal. CONSTITUTION:When the time information obtained from a digital audio data signal on a magnetic tape 21 is a large data, a change-over switch 14 is switched to a frequency divider 13 side by a time information read-out circuit 20. Thus, a frequency dividing signal dividing an audio sampling frequency fs to 1/L is supplied to a phase comparator 15. By the comparator 15, a phase comparing signal comparing this frequency dividing signal with the frequency dividing signal from the frequency divider 18 is outputted to a loop filter 16. By the filter 16, the output is outputted to a VCO 17. The one side output of the VCO 17 is frequency divided by the frequency divider 3 and supplied to a drum servo circuit 4. Then, when the reproduced time information is the small data, the switch 14 is changed over to the frequency divider 12 side by the circuit 20. Thus, the frequency dividing signal of the 1/S of the frequency fs is supplied to the comparator 15.</p> |
