Electric lamp and discharge devices: systems – Cathode ray tube circuits – Cathode-ray deflections circuits
Patent
1988-04-08
1989-01-03
Blum, Theodore M.
Electric lamp and discharge devices: systems
Cathode ray tube circuits
Cathode-ray deflections circuits
358 10, H01J 2970, H01J 2976
Patent
active
047959487
ABSTRACT:
In a video display apparatus having a service mode of operation, a vertical deflection circuit includes a vertical deflection winding coupled to a DC blocking capacitor. An output stage is coupled to the vertical deflection winding at an output terminal. A vertical sawtooth voltage generator is coupled to a driver stage for driving the output stage at a vertical rate in a sawtooth manner to generate a sawtooth deflection current in the deflection winding and for establishing a DC operating voltage level at the output terminal that charges the DC blocking capacitor. The sawtooth generator includes a second capacitor that, during normal operation, is charged in a sawtooth manner via a resistor for developing a sawtooth signal. A service mode switching circuit is coupled to the resistor for asserting the service mode of operation by preventing the charging of the second capacitor via the resistor. A DC feedback loop maintains the DC blocking capacitor charged during the service mode.
REFERENCES:
patent: 4272777 (1981-06-01), Fitzgerald
patent: 4694226 (1987-09-01), Wilber
patent: 4731564 (1988-03-01), Pan et al.
A technical manual, "The CTC 85 Color Chassis Technical Manual" dated 1977, pp. 35-44 and deflection and power supply drawing.
A technical manual "RCA CTC 136 Color Television Basic Service Data" dated 1986, pp. 1-16 to 1-20, cover sheet and a schematic drawing.
U.S. Application RCA Docket No. 84,965 entitled, Deflection Current Correction Circuit, in the name of J. A. Wilber, the applicant of the above captioned patent application, and filed concurrently herein.
Blum Theodore M.
Henig Sammy S.
Laks Joseph J.
Rasmussen Paul J.
RCA Licensing Corporation
LandOfFree
Vertical deflection circuit with service mode operation does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Vertical deflection circuit with service mode operation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vertical deflection circuit with service mode operation will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2170172