What are these hot shoe adapters? Trigger voltage reducers?

Thanks. I've googled voltage reducers, and I only find the Wein model.

If not, what are they?

They look a bit elaborate and 'homemade' for a voltage-reducer.

Where did you get them?

Unscrewing them and looking at the cct board might give some clue. Or 'buzzing' them out with a multimeter to see if there are any passthrough connections.

No sign of a optical trigger so probably not a simple slave, they look too small for radio triggers & I cant see any other connectors (PC etc).

Both connectors appear to be of the same type so they're probably not adapters between different standards (Sony proprietary to standard, or having pins in different places...)

I suspect they serve a similar purpose to the Wein models a multimeter should confirm this if a voltage >6V is put on the flash side & the camera side only reads 5V.

They COULD just reverse the voltage polarity of the trigger pins but I don't think that actually effects usage of flash. Again testing with a multimeter will indicate.

Thanks all for the contributions, I needed to pick up my meter and I needed a moment from crisis for hobby stuff. Turns out the negative probe on my meter has a hard plastic sheath around the tip, leaving just a pinpoint. Fine for detail work, not so much for tight spaces. It does not fit into the outside shoe slots, to reach the metal contact there.

I got some readings using the positive probe in the pc hole, and tripping the flash. The range of 13.9v to 4.9v that i got fits with the 14.1 shown on the dpanswers website voltage list for the Vivitar 2500 i was measuring.

Unfortunately, by the time i (later) put my mystery adapter on the same 2500, my meter had stopped reading anything. The display shows strong visible zeros, but never budges from that. Maybe I blew out a probe?

Whatever, I will need to have a functioning tester - this one says every battery in the house is dead... ;-)

I'll get back to you.

Even if these things prove to be voltage reducers, it doesn't answer how they came to be. If home or shop made, the assembly quality is high.

I'll try taking one apart.

Thanks again/

P.S. I read that reverse polarity is not at all good for digital slrs - not sure if it makes a difference in the mechanical cameras, or old TTL systems.