100% true. I had an arcade with a crane machine and quite often I would walk past it to see 200 credits on the display.

I was well aware of this from "back in the day" - it was such a problem that LAI added a small board with an antenna that would disconnect the mains for a few seconds and re-boot the machine if it sensed a spark, thus zeroing any credits.

If you have ever seen this board in one of your arcade machines now you know what it is for.

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