| 摘要 |
A control system is described for use in a television receiver adapted to receive multi-band television signals and which has a direct-access type tuning system. In such a tuning system, the receiver employs at least one local oscillator, the output of which is applied to a prescaler for dividing down the frequency of the oscillator signal. Frequently, the oscillator signal fluctuates in amplitude as the oscillator is tuned from channel to channel and from one frequency band to another frequency band. To compensate for such amplitude fluctuations, the control system confines the amplitude of the oscillator signal to an amplitude range which the prescaler can reliably handle and applies the amplitude-controlled oscillator signal to the prescaler.
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