Any post war Television Repairmen here?

Most tube TVs have two sections. No video, but has audio means the high voltage section has a problem. No audio, but video means the low voltage section has a problem.

Friends in the Navy that repaired TVs (40 yrs ago) had a go-to company schematics for the old sets. I think samswebsite.com is the current link. Those schematics are easy to follow and tell you what voltages/resistance to expect. They generally have good troubleshooting tips.

One word of warning, if you turn the set on, then off to work on it, make sure you carefully ground the capacitor that has the wire leading to the picture tube. That cap holds lots of voltage and it will light you up.