One thing that helps is having dead nuts accurate values for caps and resistors in those particular circuits. I've found that the horizontal section is especially picky about what you put in it, even a small change from what's called for in the schematic will leave the set completely dead. And even if the circuit does work correctly, you have to be especially mindful of the horizontal output tube. When I was getting my Halolight up and running, I never thought to check the 6BQ6GT tube because it was working perfectly and drawing the correct cathode current. Big mistake to assume it was OK! I happened to look over at it while doing some work on the chassis with the lights dim, and the plate was glowing bright red! Only thing that fixed that was a new tube, which doesn't glow at all. Strange though, that same tube in my Philco works just fine...
Ah well, I don't pretend to want to understand these things. It's enough that I enjoy watching them while they are around.
