RCA 21CT55 #8802897 is Dead

[miniman82]

Originally Posted by Tomcomm

an occational 40+kv non loaded run with no 6BK4 reg the little 3A2 EHV rect arcs across its full 2in length.

And what are you hoping to accomplish by doing that?

Im using my original 21FBP22A rare-earth gray screen I installed in place of the 21AXP22 in '64. This is the last and IMHO the best roundy CRT. RCA rates it's ultor at 27.5kv and their data sheet states "Brilliance and definition decrease with decreasing ultor voltage".

Again, you need to stop misquoting the tech sheets. 27.5 is design maximum, not a 'rated value'. Here's a link to the PDF: http://frank.pocnet.net/sheets/049/2/21FBP22.pdf

Any time you operate the tube beyond it's deign center values (found on page 4, which clearly state 20-25kv), you open yourself up to excess x-ray production, and an increased instance of electrical shock or tube destruction from arcing. I caution anyone on these forums from doing anything you're attempting here, I feel it's unsafe on a number of levels as you've already demostrated by destroying a flyback.