| 摘要 |
The retrace pulse voltage developed by a horizontal deflection generator is applied to the primary winding of a flyback transformer. The voltage at an intermediate point of the flyback transformer high voltage winding is rectified and filtered to produce an intermediate, DC high voltage. A pulse forming circuit is coupled to a secondary winding of the flyback transformer to produce voltage pulses repeating at the horizontal deflection frequency. The amplitude of the pulses is parabolically modulated at a vertical rate. The amplitude modulated pulses are rectified and filtered to produce a parabolically shaped vertical frequency voltage. The voltage developed across another flyback transformer secondary winding is waveshaped by an LC resonant circuit to produce a sinusoidal or a substantially parabolically shaped horizontal frequency voltage. The intermediate DC high voltage and the parabolically shaped vertical and horizontal frequency voltages are summed to produce the focus voltage. |
