Sanford SG / SG48 electromagnetic chuck test

I let the smoke out of my surface grinder the other day. I thought I had fried it but it turns out the insulation on the leads to the chuck had dried out and flaked off causing a short. After some realty finicky soldiering I was able to put new leads on the chuck and test out the original type 80 full bridge rectifier vacuum tube circuit on my bench. Measured voltage at the output of the 4MFD capacitors was 145 volts DC. I’m not sure what it is “supposed” to be, but the fact that the 90 year old vacuum tube still works and glows in the dark is kind of amazing.

Видео Sanford SG / SG48 electromagnetic chuck test канала Tharkis