| 摘要 |
PURPOSE:To perform the reproduction of a normal voice signal, by switching a clock and the operating speed of a generating means corresponding to the transmission speed of the reproducing digital signal, from a reproducing digital signal. CONSTITUTION:When the operating speed of the generating means is switched, the frequency of the clock outputted from the generating means is also switched corresponding to the above switching, and the clock synchronized with the reproducing digital signal can be obtained at every transmission speed of the reproducing digital signal. For example, the transmission speed of a digital signal A arrives at speed fm twice as that of a normal speed, the free oscillation frequency of a VCO17 becomes a frequency near fm by the impression of a voltage V of low level from a change-over switch 6. Thereby, the output of the VCO17 can follow to the digital signal A, whose transmission speed is doubled, and similarly as in a case of normal transmission speed, it is possible to fetch the digital signal A correctly at the leading edge of the clock (phi) at a D-FF15. |
