| 摘要 |
PURPOSE:To simplify the constitution of a video disc player by synchronizing respectively a reproduced vertical synchronizing signal and a reproduced horizontal synchronizing signal to an external vertical synchronizing signal and an external horizontal synchronizing signal. CONSTITUTION:A phase locked loop PLL11 generates an auxiliary horizontal synchronizing signal FHS having a prescribed relation to a frequency of the external synchronizing signal. Then, a PLL control section 22 controls the PLL11 in response to the phase difference between the external vertical synchronizing signal FVO and the reproduced vertical synchronizing signal FV so as to change the relation between the frequencies of the signals FHS and FHO. Further, the phase between the signal FHS and the reproduced horizontal synchronizing signal FV is compared by a phase comparison section 17 and a drive control section 19 controls the rotation of a video disc based on an output of the result of the phase comparison. Then, the signals FH and FV are synchronized respectively by the external horizontal synchronizing signal FHO and the external vertical synchronizing signal. |
