| 摘要 |
PURPOSE:To correct the distortion of a horizontal deflecting current by an extremely simple circuit configuration, and to eliminate the left and right pincushion distortion by providing a variable gain amplifier, and impressing a parabolic waveform signal amplified by this amplifier to a saturable reactor for modulating a horizontal deflecting current though a current amplifier. CONSTITUTION:A parabolic signal P outputted from a parabolic waveform generator 13 is supplied through a resistance 14A to a non-inversion input terminal (+) of an operational amplifier 14B for constituting a variable gain amplifier 14. When the parabolic waveform signal P is inputted to the variable gain amplifier 14, a parabolic waveform signal P' is obtained, and a current value is amplified by a current amplifier 15, and impressed to a vertical deflecting side winding 16a of a saturable reactor 16. When the parabolic waveform signal P' is impressed to the vertical deflecting side winding 16a of the saturable reactor 16, the amplitude value of a horizontal deflecting current IH flowing to a horizontal deflecting winding 17 is modulated in accordance with an amplitude variation of the parabolic waveform signal P', and a constricted distortion of the upper part of the display picture can be reduced. |
