| 摘要 |
In an oscillator circuit having an output oscillator in a phase-locked loop, certain problems occur in achieving a high adjustment accuracy of the desired frequency because the influence of the characteristic of the voltage-control oscillators in a circuit driving a phase discriminator in the phase-locked loop is included in the frequency adjustment. To obtain an oscillator circuit with faster and more accurate adjustment of the frequency in each case desired, a difference frequency measuring arrangement (26) with a counter (33) is provided which, on the one hand, is connected to the output (13) of a voltage-controlled reference frequency oscillator (14) and, on the other hand, to the output of a frequency standard (29). The difference frequency measuring arrangement (26) is followed by a computer (22), one output (21) of which is connected to a digital/analog converter which precedes the reference frequency oscillator (14). The computer (22) contains a further output (22) for coarse adjustment, which is connected to a frequency divider circuit (5) in the phase-locked loop (1), and an input input (36) for selecting the respective frequency. The oscillator circuit provides for accurate and fast adjustment of frequencies with relatively little circuit complexity. <IMAGE>
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