I'm wanting to start making reproduction cartridges, and, after some research, I've some questions:
I'd like to make an Earthbound cart, and looked for donors in http://www.nesreproductions.com/ , and MC Kids, which I have, is compatible, IF a battery mod is made. I've tried to look up info and tutorials, but found nothing. Of course I could get a compatible one, but NES carts in Brazil are quite expensive compared to US, and ebay shippings are too high.
So, what is this mod? Is it expensive or complicated to make? Is there any tutorial.
Any help is appreciated, thanks in advance!!