I lucked into a Graflex Flash Synchronizer at my local flea market. The bottom plate says 3 cell and the patent no is 2310165. It has light wear, it was clearly used, although not roughly. There is some rust on the inside. All the pieces seem to be there from comparing it to the owners manual. It has the cable to connect to the camera. Is anyone aware of a way to test if it it still works without connecting it to an actual camera? Any help would be appreciated. I have no interest in keeping it, I plan to sell it, I'd rather sell it to a camera collector instead of a scifi collector, I'm kind of a purist that way, but to be honest, it would go wherever I get the best offer. Does anyone know a place it might get better exposure to collectors other than eBay?

Thanks,

If you have flash bulbs that fit the syncronizer then put batteries in and short out the two prongs on the cable, that should fire the flash bulb. That would test both the cable and the syncronizer.
Otherwise hook up a VOM multimeter to the bulb contacts, set the meter to volts DC and short the prongs on the cable again, if it works there should be a voltage reading, you may have to hold the short for a second let the meter "catch up" since meters are meant to read continuous volts not short bursts.
This should work with a continuity setting on the meter too.