Restoration question from beginner

[MadMan]

"Really need a CRT tester" is kind of misleading. When you test the tube and it shows 'dead' they will say that the tube is 'asleep' and you will not know for sure if the tube is good or bad until you have it plugged into a fully functioning set. Of course, if you had a fully functioning set, you wouldn't need a crt tester. So really, you don't need a crt tester.

As for the metal cone crt, here's another tip. They never test good. From my personal experience with two of them, they test dead or very weak, despite being ok. I've also seen this in a couple of shango's youtube videos, same thing. Also, common knowledge says that they are very rarely any good. Yet somehow I managed to get 2 good ones out of 2. I think where that comes from is that they probably test bad, but are not necessarily bad. There must be something about the metal cone tubes that don't test properly, or, perhaps, they can still make a decent picture despite being very worn out.

My point is, testing the tube will yield no useful result. Unless, perhaps, you are such a seasoned repairman that you can divine the true meaning of the test results, be they bad or good. If you say the tv set will produce a white spot on the center of the screen, the crt is - at minimum - somewhat usable. Do not run the set for very long, the spot will burn into the screen.