Circuitry for demagnetizing the mask in a color picture tube

Details Circuitry for demagnetizing the mask in a color picture tube Circuitry for demagnetizing the mask in a color picture tube

1989-07-11

1992-03-03

Pellinen, A. D.

Electricity: electrical systems and devices

Control circuits for electromagnetic devices

Systems for magnetizing, demagnetizing, or controlling the...

315 8, H01F 1300, H04N 929

Patent

active

050937553

ABSTRACT:
A circuit for demagnetizing a mask in a color picture tube of a television receiver, in which a resistor with positive temperature coefficient is applied to the input alternating current when the receiver is turned on. A bridge rectifier is connected with one terminal, to a first pole of the alternating current source, via the demagnetizing coil that is mounted on the picture tube, and the resistor. The bridge rectifier has another terminal connected to a second pole of the alternating current source. A variable electronic switch interconnects the direct-current output terminals of the bridge rectifier. The variable electronic switch is controlled to continuously decrease current flowing through the demagnetizing coil to zero. For this purpose, a controlling voltage is obtained from a winding in a horizontal-frequency synchronized power-intake stage by flyback rectification. A feedback circuit is connected to a delay network and to the variable electronic switch for opening the latter completely after a time interval determined by the delay network.

REFERENCES:
patent: 3582721 (1971-06-01), Hoorn et al.
patent: 3733524 (1973-05-01), Cooksey et al.
patent: 3784868 (1974-01-01), Shinkai et al.
patent: 3955115 (1976-05-01), Manske
patent: 4445072 (1984-04-01), Fredres
patent: 4710697 (1987-12-01), Tardy

Affiliated with

Also associated with

Rating

Circuitry for demagnetizing the mask in a color picture tube does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Circuitry for demagnetizing the mask in a color picture tube, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Circuitry for demagnetizing the mask in a color picture tube will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-276540