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I've got an old Nintendo Game Boy, with a number of games for it. The problem is that most of these games don't load any more, and I suspect that's an issue with the contacts either in the unit, or in the game card.
Looking into the contacts on the game cards, a number of them have metal oxide marking on them, especially where the gold plating has worn away. The contacts on the Game Boy itself aren't faring much better.
Is there anything I can or should do to rejuvenate the contacts so I can use it again?