| 摘要 |
PURPOSE:To output a stable signal of necessary frequency by controlling the frequency of a low-frequency oscillator on the basis of the phase difference between an output signal and an input reference signal, and converting the frequency of the output of the oscillator by the output of another oscillator. CONSTITUTION:The voltage-controlled oscillator 6 of relatively low frequency outputs a signal of frequency (f) whose frequency and phase are controlled by the output voltage of a loop filter 3, and it is multiplied by a mixer 7 by a signal of frequency f0 that a fixed-frequency oscillator 8 outputs. Then, a signal of (f0+f) and a signal of (f0-f) appear at the output of the mixer 7. A band-pass filter 9 allows the signal of (f0+f) to pass and outputs it. |
