| 摘要 |
PURPOSE:To realize a stable control for the number of rotations of a recording medium, by recording the digital signal comprising the synchronous and data signals with a modulating system of the synchronous signal part different from that of the data signal part and then demodulating the above-mentioned synchronous signal during the reproduction. CONSTITUTION:An audio signal I is converted into a digital signal through a PCM modulator 1. Both the digital signal received a PCM plus a synchronous signal are delivered to the side of output (c); while a signal showing the period of the synchronous signal is produced at the side of output (b). The signal of output (c) is supplied to a modulator 2 and an FM modulator 3. Then a pilot signal (d) delivered from an oscillator 5 is gated by the signal of output (b) via a gate circuit 4, and the output signal (c) receives an FM modulator by a burst signal (e). |
