| 摘要 |
<p>A phase controlled oscillator comprises a first sweeping oscillator producing an output voltage controlled by a control input signal and a first sweeping signal within a limited output voltage amplitude, a second sweeping oscillator which producesa second sweeping signal having an amplitude smaller than that of the first sweeping signal supplied to a phase locked loop, the phase relation of input and output signals of the second sweeping oscillator being selected such that it stops oscillation when the loop is in a locked state, and a control circuit adapted to hold the output voltage of the first sweeping oscillator. With this construction, it is possible to stably pulling into synchronism in the frequency changing range of the voltage controlled oscillator even when the holding-in range of the phase locked loop is narrower than the frequency changing range of the voltage controlled oscillator.</p> |
