| 摘要 |
PURPOSE:To always set approximately the inter-music space time at a fixed level in a reproduction mode by using a signal detecting the absence of the reproduction output of an audio signal and a subcode signal to perform the accurate control so that the inter-music space time is set at a prescribed level. CONSTITUTION:An audio signal S obtained by mixing L and R audio reproduction signals via resistances R1 and R2 is used as the input of a comparator 2. The comparison reference voltage Vref is used as the other input of the comparator 2. The comparator 2 sets an output A at H while S>Vref is satisfied and then set at L in the case of S<=Vref. Therefore, the presence or absence of the signal S can be decided by the H or L of the output A of the comparator 2 as long as the Vref is at a level where the signal S has no sound. Then the subcode signal read simultaneously out of a compact disk with the output A is supplied to a microcomputer 3 to perform decision and processing. Based on the result of decision, a disk driving system 4 and an optical pickup driving system 5 are controlled. Thus the production of an approximately fixed inter-music time is made possible for all the time. |
