Picture tube screen grid potential control

Details Picture tube screen grid potential control Picture tube screen grid potential control

1985-02-26

1987-09-08

Blum, Theodore M.

Electric lamp and discharge devices: systems

Cathode ray tube circuits

Cathode-ray deflections circuits

315383, 358243, H01J 2952, H04N 568

Patent

active

046926690

ABSTRACT:
A transistor with its collector connected to a point near the screen grid in the resistor network which feeds voltage from the high voltage rectifier of a picture tube to the screen grid electrode and its emitter connected to ground has two control circuits connected to its base electrode. The first control circuit (56) is a threshold circuit responsive to a voltage proportional to the beam current of the picture tube for making the control transistor provide a short circuit between the picture tube screen grid and ground, and thereby preventing a burnout when there is persistent excessive beam current. The second control circuit (58) acts on the base electrode of the control transistor to set the screen grid voltage of the picture tube at a desired value in normal operation, for example in accordance with the pulse width of a train of pulses of settable pulse width.

REFERENCES:
patent: 4042858 (1977-08-01), Collette et al.
patent: 4488181 (1984-12-01), Haferl

Affiliated with

Also associated with

Rating

Picture tube screen grid potential control does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Picture tube screen grid potential control, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Picture tube screen grid potential control will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2160397