Dual mode automatic fine tuning

Details Dual mode automatic fine tuning Dual mode automatic fine tuning

1979-08-17

1981-11-10

Wolff, John H.

Facsimile and static presentation processing

Facsimile

Specific signal processing circuitry

H04N 544

Patent

active

043001653

ABSTRACT:
A digital staircase search is provided for the automatic fine tuning (AFT) control of a television receiver to extend the range of fine tuning. The staircase search generator is of digital construction to provide the capability of holding the level of search voltage obtained when the picture carrier is detected and to realize discrete steps of tuning voltage change, each step being within the pull-in range of the AFT. The search signal generated has each step of the staircase of opposite polarity so that sweep of the tuning voltage is bi-directional. The absence of a picture carrier activates operation of the search mode and disables the automatic fine tuning control. Upon detection of the picture carrier a harmonic of the horizontal sync pulses in the detected carrier is converted to a control signal which disables the search process and enables operation of the automatic fine tuning control. The automatic fine tuning control operates from the step of the staircase held upon search termination.

REFERENCES:
patent: Re27329 (1972-04-01), Mayle
patent: 2910530 (1959-10-01), Clark
patent: 3584141 (1971-06-01), Fujiwara
patent: 3610817 (1971-10-01), Bridgewater
patent: 3715495 (1973-02-01), Takezaki et al.
patent: 3949158 (1976-04-01), Rzeszewski et al.
patent: 3965288 (1976-06-01), Yamada et al.
patent: 3967057 (1976-06-01), Tsukamoto et al.
patent: 4025953 (1977-05-01), Sideris
patent: 4038689 (1977-07-01), Rzeszewski et al.
patent: 4041535 (1977-08-01), Rzeszewski et al.

Affiliated with

Also associated with

Rating

Dual mode automatic fine tuning does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Dual mode automatic fine tuning, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dual mode automatic fine tuning will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2364795