Samsung pn51d450a2d horizontal lines on the screen

[andy]

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[MRX37]

Originally Posted by andy

I recently worked on a Samsung plasma which black horizontal lines running through the picture (mostly in the top half of the screen). Unfortunately, it was caused by a bad plasma panel.

There seemed to be a manufacturing error where the ribbon cables were bonded to the glass. The ribbon cables connect to fine metal traces on the glass (possibly silver). The traces are covered with an insulating coating to protect them except for the area that is bonded to the ribbon cables.

Unfortunately, they left a gap between the edge of the ribbon cables and the insulating coating. The silver traces in this area are exposed to the air are erode over time (possibly electromigration, or oxidized from ozone generated by the high voltages). On my set you could hear and see arcing across some of the open traces.

It looks like Samsung had intended to seal the gaps with silicone, but it only covers the backs of the ribbon cables, and misses the gap.

That seems to be what the issue here is. The Y buffer board tests good. Meaning the IC's don't have any shorts far as I can tell. On youtube there are videos showing how to test for shorts. I did that and found none.

Unless there's another simple test I can do then I'm just gonna assume it's the panel.