There are just a few videos in existence showing an individual assembling the particular elements within the envelope. We see people using very small spot-welders being used, fabricating tiny metal structures...nowhere do we see a so-called "exploded diagram"...are these tiny structures a true industry secret?
Let's see if we can find diagrams of these structures...& try to improve performances by analysis & optimization.
-------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
Let's see if we can find diagrams of these structures...& try to improve performances by analysis & optimization.
-------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
what is the goal ?
to teach tube makers how to improve tube design ?
to learn from internals how to improve amp design ?
secrets ?
to get a feeling for the complexity involved you could read those 1000 pages published by rca about tube design :
http://tubebooks.org/Books/Atwood/RCA 1962 Electron Tube Design.pdf
RCA's Electron Tube Design is a pretty thorough compendium on tube design, but I would recommend starting out with Spangenberg's book "Vacuum Tubes" and Deketh's book "Fundamentals of Radio-Valve Technique". Much more readable. Probably scans of those on the same site, or used books.
If you just want some guide to making a super output tube, get someone to make a 6JD5 with a grid 2 installed. (must have the 6JD5 frame grid 1 for a high quality internal triode ) Higher spacing between grid1 and cathode is the secret to linear tubes. A frame grid 1 helps get the gm back up then.
If you just want some guide to making a super output tube, get someone to make a 6JD5 with a grid 2 installed. (must have the 6JD5 frame grid 1 for a high quality internal triode ) Higher spacing between grid1 and cathode is the secret to linear tubes. A frame grid 1 helps get the gm back up then.
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Loaded up those pages & started reading...likely will take a nice chunk of time to get thru it...but will have to load it on my other machine...already learning about "emitters" of electrons.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
Theres a guy building tubes as a hobby in his garage, using many leftover NOS parts from Mu-inc.
He has a couple of videos on youtube explaining what he does.
Appearantly he even has two Logan grid lathes. Which are rare nowadays
He has a couple of videos on youtube explaining what he does.
Appearantly he even has two Logan grid lathes. Which are rare nowadays
A link available to the video with the Logan grid winding lathe?
I have a Logan 10" metal lathe (sold as a Montgomery-Ward lathe back in the 50's) that has the thread cutting gear box, can do up to 224 threads per inch. But a frame grid probably needs more like 1000s per inch and elaborate tension control for the tiny grid wire. Curious to see how they did that. Would probably use some stepper motors now.
I have a Logan 10" metal lathe (sold as a Montgomery-Ward lathe back in the 50's) that has the thread cutting gear box, can do up to 224 threads per inch. But a frame grid probably needs more like 1000s per inch and elaborate tension control for the tiny grid wire. Curious to see how they did that. Would probably use some stepper motors now.