Circuit for changing the vertical position of a frame in wide-screen television

摘要

A circuit for eliminating the vertical line-jump phenomenon which is produced by instability in the servo control in the VCR fast-forward or still-frame operating modes comprises a vertical pulse delay device 101 for delaying the vertical pulse from a vertical and horizontal oscillator 100 for the period of a particular number of horizontal lines; a vertical driver section for converting the delayed vertical pulse delivered by the vertical pulse delay 101 into a vertical sawtooth-wave pulse and for correcting the converted vertical sawtooth-wave pulse in accordance with the vertical position signal fed back to the input; a vertical deflection amplifier section for amplifying the corrected sawtooth-wave pulse supplied by the vertical driver section 102; a vertical position detector section 105 for detecting the vertical position of a frame due to the signal supplied by the vertical deflection amplifier section 103 via a vertical deflection coil (V-DY) 104; a microcomputer 106 for controlling the function of the vertical pulse delay 101 and of the vertical driver section 102; and a feedback of the signal supplied by the vertical position detector section 105 and a vertical position control section 107 for controlling the vertical changeability of the position of a frame by controlling a signal, fed back from the vertical position detector section, in accordance with the control signal from the microcomputer. <IMAGE>