I just did this mod as well, I bought Nor's dipswitch board but found out my cart had the ram errors (board was fine, BTW) Found a 5v source on the cart and added a jumper to the VCC pin. Before adding the jumper to the VCC pin had 1.3v output which is not enough. I figured this out because the VCC was outpin 5v when connected to the daughterboard that the 138 in 1 came with.
I hope Wu_swordsman has figured this out too.
pzlate, are you doing the sound fixes on that cart? If so I'm trying to that next but have questions, like how caps are needed etc.
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