| 摘要 |
PURPOSE:To stabilize operation by a method wherein the current meter of the system demodulating the phase modulation signals of supersonic waves caused by Ka rma n whirl the initial set value of the voltage control phase deviation circuit is initially set on the optimum value through the reset circuit. CONSTITUTION:The supersonic waves phase modulated by Ka rma n whirl become one imput V5 of the phase comparator 6. The voltage control phase deviation circuit 8 generates the signals V4, wherein the phase deviation angle from the oscillation signals V1 is controlled according to the output voltage V7 of the loop filter 7, becomes the other of the comparator 6 constituting the phase synchronous loop. The phase synchronous point of said loops are existing in plurality each 2pi. The transistor 51 constitutes a reset circuit turning ''ON'' immediately after the power source Vcc is made and V7 is equal to + input voltage of 13. When said reference voltage is set at the set voltage value corresponding to the center of the minimum deviation angle and the maximum deviation angle of the circuit 8, even at the time of making as well as of building-up of the power source Vcc the voltage V7 shift to the voltage corresponding to the nearest synchronous deviation angle to quickly synchronize in phase. |
