Title:
TUNING DEVICE
Document Type and Number:
Japanese Patent JPS58104518
Kind Code:
A
Abstract:
A tuning control system includes a pulse converter for converting a digital word to a corresponding pulse signal having pulses the width or frequency of which represents the magnitude of a tuning voltage associated with a respective channel. The pulse signal is applied to a filter which produces the tuning voltage. An automatic fine tuning (AFT) voltage is generated by an AFT discriminator in an IF section and also applied to the filter to modify the magnitude of the tuning voltage to correct for any frequency deviation of the IF signal. To make the response of the tuner to changes of the AFT voltage more uniform for different channels, the AFT voltage is applied to the filter through a switch which is selectively closed in response to the pulses of the pulse signal so as to change the effective amplitude of the AFT voltage applied to the filter as a function of the channel selected.
Inventors:
BIRII UEZUREI BEIYAAZU JIYUNIA
Application Number:
JP20837182A
Publication Date:
June 22, 1983
Filing Date:
November 26, 1982
Export Citation:
Assignee:
RCA CORP
International Classes:
H03J5/02; H03J7/04; H03J7/08; (IPC1-7): H03J5/00; H03J5/24; H03J7/08
Attorney, Agent or Firm:
Satoshi Shimizu