| 摘要 |
A clock signal generating circuit for a television receiver, which generates a composite synchronizing signal and a masking signal for controlling the operation of the circuit, the composite synchronizing signal including at least two partial signals. The circuit includes a voltage controlled oscillator for generating an output oscillation signal having a predetermined frequency, a source for supplying a reference voltage corresponding to a predetermined center frequency of the oscillation signal to the oscillator, a phase comparator for comparing the phase of the oscillation signal output from the oscillator with the phase of one of the two partial signals and generating a phase error signal corresponding to the difference in phase between the oscillation signal and the one of the two partial signals for adjusting the frequency of the oscillation signal, a circuit responsive to the masking signal for interrupting the comparison by the phase comparator for a period of time corresponding to the period of another one of the two partial signals, a switch for interrupting the supply of the reference voltage to the oscillator during the period when the mask circuit is interrupting the comparison, and a device for maintaining the voltage supplied to the oscillator at a level corresponding to the voltage supplied at the time of the interruption by the switch and the mask circuit.
|
