Nickel used for cathodes needed to be ultra-pure, as even tiny amounts of certain impurities (particularly silicon) would greatly reduce tube life in some applications.

The amount of chemistry and materials science that went into tube manufacture is quite amazing. It was nearly as complex as semiconductor fabrication is today. Entire industries sprung up (and died) to service the electron tube business.

The closest thing I have seen to a comprehensive book on making tubes is the 1962 RCA manual "Electron Tube Design". Available here:

http://www.tubebooks.org/Books/Atwoo...e%20Design.pdf

Tube Building
 

Greetings,
As to the above post, is the rest of the RCA book "Electron Tube Design" available anywhere? I find the information from the link interesting but would love to see the rest.:tears: Can it be downloaded or purchased from anyone?

Thanks,
Dennis

Entire book available here:

http://www.tubebooks.org/Books/Atwoo...e%20Design.pdf

and here:

https://archive.org/details/RCA_1962...on_Tube_Design