| 摘要 |
<p>A deflection switch (Q1) of a horizontal deflection circuit (250) is coupled to a retrace resonant circuit (100) that includes a horizontal deflection winding (LH) and a first retrace capacitance (C1). A flyback transformer primary winding (W1) is coupled at a junction terminal (collector of Q1) of the deflection switch (Q1) and the retrace resonant circuit (100). A second winding (W4) of the transformer (T1) is coupled to an ultor voltage power supply (556). To provide side pincushion correction, a second switch (Q2), having a conduction time that is phase modulated during horizontal retrace at a vertical rate in parabolic manner, is coupled between ground and a terminal (50) of the retrace resonant circuit (100) remote from the flyback transformer primary winding (W1). The second switch (Q2) is conductive during the entire trace interval and is turned-off at a controllable instant during the first half of the retrace interval. When the second switch (Q2) is nonconductive, a second retrace capacitance (C2) is interposed between the flyback transformer primary winding (W1) and the retrace resonant circuit (100) to prevent load variation in the second winding (W4) of the flyback transformer (T1) from causing raster distortion.</p> |
