| 摘要 |
PURPOSE:To cause dependency of the frequency accuracy of a low frequency oscillating circuit upon the accuracy of a high frequency oscillating circuit by comparing the phases of the high frequency oscillating circuit and the low frequency oscillating circuit, and selectively controlling the frequency of the low frequency oscillating circuit stepwise in accordance with the phase signal thereof. CONSTITUTION:The output signal of a low frequency oscillating circuit 2 is divided down to a 1-second signal fs by frequency dividing circuits 4a, 4b, and the time is displayed by a motor driving circuit 5 and a pulse motor 6. The output of the circuit 4a and the output of a high frequency oscillating circuit 1 are inputted to a phase comparator 3, and the on and off of the transistors 2i, 2j of the circuit 2 are controlled by the output of a T type FF, so that the oscillation frequency of the circuit 2 is changed over to 2 stages. As a result, the output signal fL1 of the circuit 2 is phase-locked within 1 pulse of the high frequency signal fH. |
