DEFLECTION SYSTEM SUCH AS FOR TELEVISION RECEIVERS INCLUDING A SWITCHED MODE VERTICAL (FIELD) DEFLECTION CIRCUIT

摘要

VERTICAL DEFLECTION CIRCUIT First and second controllable switching stages are respectively coupled between a source of horizontal retrace pulses and a capacitor connected across a vertical deflection winding. A modulator is coupled to the switching stages for controlling the timing of conduction thereof relative to the timing of the horizontal retrace pulses. One switching stage charges the capacitor in one polarity with pulses of current of gradually decreasing amplitude and duration during a first portion of the vertical trace interval and the other switching stage charges the capacitor in the opposite polarity with pulses of current of gradually increasing amplitude and duration during a second portion of the vertical trace interval. The capacitor supplies scanning current of first and second polarities to the vertical deflection winding during respective first and second portions of each vertical trace interval. The energy for producing the vertical sawtooth scanning current is thus derived from horizontal (line) scanning pulses which are coupled to the vertical deflection winding.