一台东芝288D6C 彩电伴音和图像的清晰度及色彩均正常,但有行小扭故障。特征是:图像的垂直部位都有左右小扭曲,画面顶部扭曲程度明显严重,越到下边故障程度越轻。行扭属程度轻微行失步故障,是一少见比较难查找的“软”故障,涉及到开关电源、中放 AGC、同步分离、AFC 等多方面的电路。从故障现象特征分析,伴音正常无嗡声,不是 S 形大扭曲,可排除开关电源存在故障的可能性;行失步程度较轻,电视强、弱信号时故障程度不变化,再排除中 A Toshiba 288D6C color TV sound and image clarity and color are normal, but a small twisting line fault. Characteristics are: the vertical part of the image has a small twist around the top of the screen was significantly worse degree of distortion, the more down to the lower the degree of fault lighter. The line of slight degree of torsion is a step out of line fault, is a rare and difficult to find “soft ” fault, involving switching power supply, put AGC, synchronous separation, AFC and other aspects of the circuit. From the symptom characteristics of the analysis, the normal no-sound no-sounding, not S-shaped distortion, can rule out the possibility of switching power supply failure; row out of step less degree, the TV strong, weak signal does not change the degree of failure, and then excluded