| 摘要 |
In order to automatically set a predetermined frequency component of a voltage-controlled oscillator of a spectrum analyzer which is swept by a sweep voltage to a prescribed point of a frequency coordinate on a display device, the oscillator is connected into a phase control loop of a frequency synthesizer as its oscillator. This connection is by way of one switch position of a transfer switch, in which the tuning voltage supplied by a phase comparator of the control loop is supplied to a storage element and, in the other switch position, the phase control loop is opened and the output of the network connected to the storage element is connected to the control input of the oscillator. The network is controllable by way of a control voltage such that the stored tuning voltage may be supplied to the control input of the oscillator as a reference voltage for the sweep voltage.
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