CRT UPDATE !Thanks for your comments. Yes Sphere might be a source... when I am rich. At least it's a ray (pun !
) of hope !
I have just managed to pull this frreaking CRT out !
Lots of "WD40" (well, something similar from FACOM, what I had laying around) did nothing.
No amount of wiggling would break it loose. I was totally baffled.
Then I thought hmmm... lemme think : there is obvious signs that this CRT has been messed with in the past --> when I removed the bezel, there are 4 screws. behind the front panel, there are captive nuts welded to the panel. Well, as it happens two of these nuts broken off the panel and somone had replaced them with a loose nut. Which means it was a pain to remove and will be a pain to put back on, because limited access.
So, what if that guy was stupid enough to somehow GLUE the CRT to the shield, for some reason ? So I shoved a thin flat screw driver between the CRT (well, the plastic ring / trim around the edge of the CRT) and the shield, at the front. I had to shove the blade very deep, an inch or so, and work it all around the CRT... but it eventually freed the CRT, victory !!!
Now I can look at the neck to see the guts of it inside. I am not competent so don't know what to look for, but from a newbie perspective, at the least I can say that the mechanicals inside so to speak, don't look anywhere near as thin / fragile / delicate as I imagined, and there are even like white rod that act as spacers and support for the various pieces. I honestly don't see how that could get bent during shipping, or at all
I think there might be hope : I can hear something rattling in the CRT... but I can't see it INside the glass... it sounds more like it's inside the black plastic connector on the neck, that holds all the pins/terminals.
I see that the glue that holds it to the glass of the neck, is hard, dried and broke free. It's not holding to the glass anymore. So the connector can wiggle a bit, though it doesnt fell like it's going to come oiff anytime soon. The wires inside must be quite thick and holding it well in place.
So, I guess the rattling noise inside must be pieces of the glue that are wondering about. So maybe the arcing sound are happening not inside the CRT, but inside the socket ??
So I could try removing the socket to inspect it, and maybe get rid of it and solder wires to the CRT and connect it to the scope this way. I mean, just to diagnose it, see if that fixes the problem. If it does not then the damage is inside the CRT and it's hopeless, but if does come from the socket then... scope is back to life
The problem is that I don't have fine cutting tools like a Dremel or the like, to cut the cnnector open. So... the repair might have to wait until I can afford a Dremel.