I always make a label telling when the battery was swapped in an unpopulated area on the board, typically on the left side. For GBA games, I stick the label on the back side of the PCB instead, since it's unpopulated on that side. This way if people question when the battery was changed last, they can tell, and by who. Quick and easy turnaround to make a few bucks.
(And yes, I'm wearing rainbow pajamas that are 2x too big for me.)
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(And yes, I'm wearing rainbow pajamas that are 2x too big for me.)
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