| 摘要 |
In a circuit arrangement including at least one control loop composed of a controllable oscillator for producing an a.c. output signal whose frequency is a function of the value of a control signal thereto, a frequency/d.c. signal converter connected for producing a d.c. output signal which is a function of the frequency of the oscillator output signal, and a signal comparator having two inputs and an output, with one comparator input receiving a signal corresponding in value to the converter output signal, and the oscillator receiving a control signal corresponding to the signal at the comparator output, the circuit arrangement further including an a.c. signal source, and a second frequency/d.c. signal converter connected for producing a d.c. output signal which is a function of the frequency of the a.c. signal produced by the source, with the other comparator input receiving a signal corresponding in value to the second converter output signal. An adjustable signal control arrangement is connected between the output of the second converter and its associated comparator input for applying to the associated comparator input a signal which differs in value from and varies in proportion with the output signal from the second converter.
|
