Changhong color TV H2535K line pushes power supply filter failure causing interference failure - Database & Sql Blog Articles

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The Changhong color TV model H2535K experienced an issue where the power supply filter caused interference and faults in the image display. The image showed visible interference, as shown in the attached pictures. During the repair process, it was observed that the interference changed with the brightness level, and the position of the interference varied accordingly. When the acceleration voltage was reduced, the fault disappeared. As the acceleration voltage increased, the interference moved from the center to the top and bottom of the screen, splitting into two bands that moved up and down. At this point, the middle part of the image appeared normal. Since the fault seemed to be related to a slight high-voltage ignition, the initial assumption was that the problem might be due to issues with components such as the high-voltage package or the CRT socket. However, after replacing these components, the fault remained unchanged. Further checks were performed on the ABL circuit, the acceleration electrode, B+ voltage, field power supply, and line vibration power supply filters, but none of these replacements resolved the issue. Upon careful observation of the faulty image, it became apparent that the problem might be related to the horizontal sync circuit. When the power supply filter capacitor for the horizontal deflection was replaced, the interference disappeared completely.