HIGH VOLTAGE FLUCTUATION DETECTION CIRCUIT FOR TELEVISION RECEIVER

摘要

PROBLEM TO BE SOLVED: To detect accurately actual high voltage fluctuation to correct an apparent amplitude change on a picture tube screen due to a high voltage fluctuation of a television receiver. SOLUTION: A high voltage fluctuation signal generated by a flyback transformer focus block 2 and a screen capacitor 6 and detected from a ground side output terminal of the focus block 2 is a signal whose high frequency component is attenuated in comparison with actual high voltage fluctuation and given to a circuit converting a frequency characteristic of the detection signal, in which the amplitude is corrected. Or a resistor is inserted between a screen voltage output terminal of the flyback transformer 1 and a screen terminal of a picture tube so as to set a cut-off frequency of the low pass filter proper for detecting a high voltage fluctuation.