Focus voltage regulation circuit for cathode ray tubes

摘要

A voltage supply circuit for cathode ray tubes in which a horizontal drive pulse is supplied to a flyback transformer and a flyback pulse to be derived from the flyback transformer is supplied as a cathode voltage, a grid voltage and an anode voltage for a cathode ray tube, to provide a focus voltage regulation circuit for cathode ray tubes is disclosed wherein the flyback pulse to be derived from a part of the flyback transformer is rectified to obtain a direct current voltage which is in turn varied for application as a cathode voltage and/or a grid voltage or superimpose onto the anode voltage so that a potential difference between the cathode voltage, the grid voltage and the anode voltage is variably and relatively regulated.