NES has wavery video???

[Wolfshadow]

I acquired an NES from ebay that was listed as 'for parts' and tested it, and she worked, much to my delight. She plays fine, but the video is not crisp... There are wavery lines distorting the image horizontally... It doesn't seem to effect game play but I'm not sure what it is that is causing this... It reminds me of the voltage screws on a DS lite to control screen flicker... any ideas, anyone??

[celerystalker]

If I was guessing, I'd think a bad resistor maybe. There's probably a section of badly regulated current on the path to the video out. Just a guess.

[Pikkon]

I would recap the motherboard or maybe it's the psu.