Timing of deflection waveform correction circuit

摘要

A video display apparatus has a controllable, synchronized switch to control current conduction in an inductance. Responsive to a switching signal, a modulator switches the conductive states of the controllable switch. A signal generator is coupled to a source of retrace pulses, for generating at an output a horizontal rate sawtooth signal. The sawtooth signal comprising a first ramp of duration within the first half of the retrace pulse and a second ramp of duration equal to the trace interval. A source of a modulation signal is coupled to a means for generating the switching signal. Responsive to the modulation and sawtooth signals the means generates the switching signal having a first polarity which inhibits conduction in the switch and a second polarity which enables conduction in the switch. The first polarity of switching signal commences within the first half of the retrace interval and the second polarity commences within the remaining time of the horizontal interval.