Fixing wavy vertical lines in the NES video out

Does your NES has wavy vertical lines line a bunch of ellipses  all over the screen, like the photo at right? It's causes by a failing power supply. The 60hz AC signal is supposed to be filtered out by a pair of caps in the power + video silver box inside your NES, but if those caps fail you get noise like these lines, even though everything else works fine.


The caps that fail are both 100uf, one 10v and the other 25v. See photo below for the caps that need replacing. When I measured them one was essentially zero capacitance, and the other was within the capacitance spec but had about 1.5kohm ESR which is clearly nuts.


If you order replacements make sure you get one's that will fit in the box. It's quite a tight space. You might think about replacing the other two smaller caps in there since they are cheap and it's a bear to get into the space, because it's inside a soldered box that requires a lot of solder sucker and solder wick to get open. There are 3 tabs and 4 pins that need to be 99% clean of solder before you can open it. 

These are cheap caps, they should cost well less than $1 each. The larger cap would probably cost more like $5, but luckily seems to be fine (I didn't desolder it to check, but I can confirm that leaving it in did not hurt video performance at all).


The caps that need replacing:


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