Re: Telegraph Components

The WU rectifier I've seen was basically just a transformer, a vacuum tube (presumably a full-wave rectifier), and a capacitor mounted to a metal box base. Saw it at a swap meet several years ago and unfortunately didn't buy it, so it's not in my collection and I can't give you a picture. I presume by the end of open wire telegraphy they'd at least gone to a selenium and probably silicon rectifiers, but I don't know if this gear would have been marked with a Western Union part number, or if it would just be an off-the-shelf power supply.

Modern day... Honestly a transformer, rectifier, and cap is still probably the most rugged, reliable solution for the problem. You could do it with modern switching power supplies, but they tend to react poorly to things like lightning transients, even the bit left over after the arrestors have kicked in.

Ed, if you've got pictures of such gear, or any vintage instruments, I'd love it see it.