Stray emission reduction circuit

摘要

The most popular method for reducing stray emission effects in a cathode ray tube is to install a bleeder resistor at the flyback transformer of the tube. Such a bleeder resistor is, however, quite expensive. Therefore, the stray emission reduction circuit according to the invention differentiates the H pulse when the TV set is switched from "on" to "standby" which results in a higher duty cycle of the control transistor, implying a lower duty cycle of the horizontal output transistor HOT. This results in a lower voltage at the tuning capacitor and hence lowers the flyback peak voltage at the anode. This results in a drop of the EHT voltage.