Changhong color TV 2588K has sound and characters but no light - android

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I recently came across an interesting repair case involving the Changhong TV model 2588. This was a Toshiba-based two-chip TV that originally won a gold award when it was first launched. However, due to its complex design and high failure rate, it often developed some strange and hard-to-diagnose issues. One day, I encountered a Changhong 2588K unit that had sound and characters but no picture. The AV input showed a blue screen, and while playing VCDs, sometimes shaking the bottom plate would temporarily fix the issue. Initially, I suspected a cold solder joint, but the previous technician had already re-soldered the board multiple times, and everything looked perfect on the surface. After a careful inspection with a magnifying glass, I found that two wires connected to the P6 (VIDEO OUT) pin on the TA7680 board were loose, specifically outside of the TA7698 38. Once these connections were properly secured, the problem was completely resolved. Interestingly, this specific connection is not present in other models and isnâ€™t marked on the local schematic, which means this fault only occurs in the Changhong 2588 TV.

I also recall another unusual issue with this same model that I dealt with about eight years ago. It was quite funny at the time. The TV had a blue screen, no image, but still had sound and text. After extensive testing, I discovered that the C30 electrolytic capacitor (1ÂµF/50V) on the middle board had failed, and the parallel resistor of 560K had increased in value. I spent several sleepless nights trying to figure out what was going on, but eventually, I managed to solve it. These kinds of rare and unique faults are what make TV repair so challenging and rewarding. Each case teaches you something new, and sometimes, it's the smallest details that cause the biggest problems.

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