Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Doug, amazing artifact ! Do you have a closeup picture showing the commutator?

Cbwho: there are also small a/c  dynamos on ebay and amazon that can couple via drive belt your demo motor (or steam engine) . They come with a little red LED and will light up with only the effort of spinning with fingertips. I recently got a ~8$ “ Crocsee 3 phase ” that’s fun to experiment with.