Vintage Tube Tester
At some point, someone needed to test tubes and couldn't afford or source a factory made tube tester. But back in the days when tools were made out metal instead of plastic and could actually be repaired... folks built the things they needed. They used their tools to fix their tools and to build other tools. A piece of an old fence from the scrap wood pile became a base, and the rest is built up from there. Just plug the heavy duty grounded cord (sourced from an old drill if I'm not mistaken) into an outlet, screw in a tube, and turn the rotary switch on the side. If you've got a good tube, it'll light up. If it doesn't light up, it's time for a new one. That fuse in front will keep you safe if you've got a tube that's really on the fritz, but you're not going to want to burn it out because those old coyote bone fuses are unobtainium these days! Build your own if you want, or let the mad old coot who built this one save you the work. Makes a great desk lamp when you're not testing tubes too.
(These exposed wires do not carry electricity and are strictly for looks)