posted on Sep, 18 2019 @ 08:44 AM
My guess would be that a component or wire was jarred a bit loose when dropped.
Over the years, in storage, whatever happened to get jostled loose resettled until a circuit could be completed again.
In such cases it might work for years more, or it might "die" again simply from holding it and moving it around enough to cause the loose thing to
move around again.
If you're brave, open it and see if there are any visibly lose wires / parts and, if so, forcibly snug them back fully into place.