Possible, yes. I'm not the guy to talk to do actually design any circuitry, though. What battery is it currently powered by?
FYI the dynohubs 'naturally' put out a high frequency high voltage source. They need to be regu-ma-lated and capac-it-timated.
Caveat: I'm an M.E. just pretending (really) to know what's going on. I break more projects than I successfully complete.
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ElJamoquio didn't hate the world, per se; he was just constantly disappointed by humanity.