| 摘要 |
A tuning system for a television receiver includes a channel number generator coupled to nominal tuning memories, fine tune memories and slope factor memories. The memory outputs are coupled to a corresponding plurality of comparators which are also coupled to counters for deriving pulse-width modulated (PWM) signals corresponding to tuning information stored in the memories. The PWM signals are supplied to a tuning voltage generator where they are combined to produce the tuning voltage for the tuner. The information in the slope factor memories is based upon the slope of the tuning curve corresponding to the selected channel number. The final tuning voltage consists of the nominal tuning voltage combined with the product of the fine tune voltage and slope factor.
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