HV Arc on CTC-5

[Electronic M]

Originally Posted by Yamamaya42

"saw the neck off the CRT"?
That's an exaggeration, I assume? can't really happen... right?
Although, it does remind me of a failure I had in a BarcoData (crt) projector long ago, it had been working fine for months, clear and bright, and suddenly went dark with a loud popping sound , (hv arcing) when I took it apart, I found the HV pcb had failed , common problem on these, but not only that, a tiny crack had been blown in the blue crt, right where the inside dag ended, allowing the hv from the inside to jump to the yoke.
I could not believe what I saw, how THE HELL did that crack get there? It could not have been there before, cause it would have caused vacuum loss.
Did the hv blow through the glass? Perhaps it did...

I have not experienced it personally, but there are several accounts here of fist gen solid state Zenith color sets (CCII flatchassis) having the HV climb so high (due to safety cap failure) and the HV arcing through the bell glass to the yoke....the arcing would heat the glass, the glass would crack and the neck and yoke would drop onto the chassis....It did have to be ran in that state for a while so this story is usually told by TV repairmen about customer sets since most VKers are smart enough to turn the set off when it makes bad noises. I've heard this story repeated enough that I don't doubt it's veracity. I also had the safety caps fail on one of those sets and for the 3 seconds it took me to yank the cord I saw a rather spectacular light show.