So I've acquired this relay to add to my collection, but I'm curious about what it actually did. According to the plate, it's a GRS K DC relay. I didn't find much online, but there was a description in a Youtube video where a guy was using one as a flashing relay to run a crossing signal. Is this what it was typically used for? Is there a way to date this one? I didn't find a build date, but the cloth wire and insulation on the coils say at least 1950's.

Does anyone have any good resources on signal relays? I like collecting them. They're neat pieces of engineering that'll last much longer than any piece of software. Plus they're cheaper than airhorns.

Here are some pictures.




And here's the pinout.

Really nice specimen. I've been a maintenance electrician my whole life, I'm almost 62 and retiring, and always enjoyed working on older things like this! Have you tried to google the manufacturer? You may be able to get some info from them. I've had really old equip. to work on, and have found that a phone call will lead to someone in the know that can reveal tons of info. Good luck and happy hunting!