I have an early amberola 50 with (missing) patent plate to the right of the horn, nickle reproducer. There are numbers stamped into underside of baseplate. Experts say this one set may be serial number. They have not seen many at all with number stampings like this. Any comments welcome.
Yes, The stampings under the bed plate do vary... basically they were just Internal Edison bedplate revision stamps letting the Edison workers know what serial number revision they were building or working with at the factory when they grabbed a bedplate part and started building a machine in the factory I have come to realize. There is not much other info out there on these stampings. Tony K. :0) .... Edison Collector/Restorer.