| 摘要 |
PURPOSE:To make always the gain control voltage fixed according to the input voltage, by sampling the carrier signal by sampling pulses which hold always a fixed relation to the phase of the carrier signal. CONSTITUTION:Now, when the carrier signal is input to PLL15, the output wave having a frequency and a phase equal to those of the input signal is obtained from the output of PLL15. When pulse shaping circuit 17 is driven by this output wave, pulse shaping circuit 17 is triggerred by a prescribed level of the output wave to obtained. If pulse width shaping circuit 20 is triggerred by this trigger pulse, sampling pulses having a prescribed width required for sampling of the carrier signal are obtained. |
