|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
76.90.39.24
In Reply to: RE: Duel of the Getters-What do they get posted by Mechans on June 28, 2015 at 16:17:39
When they make the tube they remove most of the air.The last thing that's done is to "flash the getter".
This removes the remaining gases so the vacuum is more complete.
The getter material is "splashed" on the inside of the glass and continues to "soak up" the gasses that are "out gassed" from the metal parts as the tube heats and cools with normal use. This helps maintain a "clean" vacuum and that is very important to the operation of the tube.
"Also what do the different shapes e.g. "D" vs Halo vs 'Horse shoe" etc. and what do the different locations like top, bottom, and multiple vs single getters accomplish?"
Those are the mechanical structures that held the getter material before that material was "flashed". After the getter is flashed those structures have no function as to the operation of the tube but they do sometimes give us a way to determine who made the tube and when.
As an example you might learn that some makers only used "D" shaped getter holders until such and such date, then they started using "Halo" shaped getter holders....etc.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Edits: 06/28/15 06/28/15Follow Ups:
Excellent! I knew that the gettering absorbed gasses and was flashed / activated inside the tube to do just that.
What I didn't know, was what the metal "getter" structures did. We use that structure =the getter= all the time to describe tubes . What they do after activation is....nothing... That is incredible to me but completely believable. They hold the Barium flashing material while the tube is constructed then shoots its load when flashed and just sits there for the rest of its life. The gettering/flashing in my moderately sized tube collection varies widely. I have a bunch of Sylvania 6SN7 Ws with so much in some cases you can barely make out the rest of the structures, and some very well used Marconi ECC82 tubes whose faint brown gettering is a thin 1/2 inch circle at most.
Thanks for explaining what the getter structure does, that was exactly what I wanted to know.
Have any of you noticed that the flashing on the bottom of some tubes seems like it is less than that of a top tube flash? It may just look like that and not really be less.
Steve
Many training manuals from WWII years have sections on tubes and tube theory. They can explain a lot about tube construction.
One of my best references in my collection of paper is "Theory and Applications of Electron Tubes". After that, I prefer the Electronics magazines I read which have many articles about tube manufacturing/processes, sometimes specific to a company, or a company's particular line of tubes, such as GE 5 Stars.
"I can't compete with the dead". (Buck W. 2010)
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: