Trash picked this plasma for parts and found it had some bad solder joints. It powered on after reworking most of the boards and seems like it may even work.
The symptoms is, when showing a picture of bright (mostly white) intensity (within the affected area only) a vertical strip 2 3/4" wide will begin to fuzz out (just to the right of samsung logo, 16 3/8" from screen edge), and soon turns black (from top to bottom). Changing to a darker scene immediatley ater will cause the black stripe to fade back in (it fuzzes and clears up again) and it starts working just fine....
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