I've started to test the tubes but only got about 1/3 of the way through. Until I get my reading glasses it's a bit tiring.
Besides the CRT having tested so strong, all of the tubes I've tested so far test like new, even the 6T8 of which I usually have trouble finding a strong one.
They also are all RCA with date codes in 1957. It seems like they're the original tubes. I don't think they watched this set much.
The 6BK4 seems to be the one without lead in the glass. Guess I'll make sure the cover is on the HV section when I ever get around to powering this set up.
Here's an interesting article on how to use the
6BK4 to generate x-rays.
John