I have a pair of GE 211 / VT-4-C tubes, which I picked up at a ham event years ago.
They look great, but I am a little unsure of the condition. They do not appear to have been "flashed" yet; i.e., there is no silver deposit on the inside of the glass. The little pod of barium (?) is still intact inside the tube. You can see it in the photo below. Also, there is slight discoloration on the glass above the "getter" pod; it is more noticeable on this tube (second photo) than the other.
Do these conditions generally indicate anything about the tube's useability or condition? Thanks!
They look great, but I am a little unsure of the condition. They do not appear to have been "flashed" yet; i.e., there is no silver deposit on the inside of the glass. The little pod of barium (?) is still intact inside the tube. You can see it in the photo below. Also, there is slight discoloration on the glass above the "getter" pod; it is more noticeable on this tube (second photo) than the other.
Do these conditions generally indicate anything about the tube's useability or condition? Thanks!
Yes, they sure do. The second picture shows the getter has been consumed and is most likely very gassy and unusable. It's vacuum may have been compromised. The other one is difficult to say whether it's totally gone to air or just never flashed. But never having been flashed is extremely rare. You should at least have them hypot tested for gas before use. Or you could just light the filaments (10v) and see if they glow correctly. By this I mean, see if the filament color and intensity looks proper (bright and yellowish). If very gassy, or if they have air the filament will be dim or may even smoke. And with HV applied, they may show a bluish glow if gassy.
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![Blue211[1].jpg](/community/data/attachments/305/305619-18057ab1fddc067b8f12ce9de8c79fb3.jpg)
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