I want to use the new LED flashlight bulbs in optical experiments, but hit a surprising obstacle. I can’t find bulbs and sockets that are compatible.
I tried to buy E10 bulbs and sockets. These are threaded. I found them online and ordered them, and the sockets are right. But the bulbs I get seem to have PR13.5S bases, which have no threads (and no bosses for bayonet sockets either). So I found a different brand of bulb and ordered those. Again they specified threaded E10 bases and showed them in the product photos, but what arrived had no threads (or bayonet bosses).
I can’t find PR13.5S sockets anyplace. I’ve tried Amazon, Digikey, Mouser, Newark Electronics, McMaster-Carr, and just googling “PR13.5S” with phrases like “socket”, “test socket”, and “test fixture”. There are loads of bulbs, but no sockets that I could find.
PR13.5S is a geometry with a smooth cylinder, a button on one end for the second terminal, and a flange towards the other end near the light source. It’s common in flashlights where the flange comes to rest at the bottom of the reflector from the rear, and the central positive terminal on one of the batteries presses against the button. There’s no “socket” with both terminals, in the way that I think of a socket, just a place the bulb gets trapped by the first battery.
These bulbs are expensive enough that I don’t want to keep ordering ones that say they’re E10 to see if any of them actually are. I have a few of them now in the PR13.5S form.
Can anybody point me to a socket for PR13.5S bulbs? Or do I have to make one from scratch? I don’t have a lathe or mill…