new in box apparently.... 
annoyingly I bought this so I could record a few bits from the unit to help with the emulation (it's already dumped) and maybe see if there's any way to run custom code on it as I think there's internal ROM (although it's a pads, not sub-board' case, so will be tricky)
I'll have to see if I can find a suitable backplate for the battery compartment in remains of another unit, although the shells for most other units are long gone at this point.
of course given that this is missing in the first place it makes me think it's just a broken unit, and won't work even if I add something conductive there.
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