Mutual Conductance Valve Analyser

[pwdrive]

Yes, RDH4 was more for designers, it's still a useful reference book though and worth bookmarking.

I posted this up the other day, you might find the reading a bit easier, Inside The Vacuum Tube by John F. Rider, link below in case you missed it:

http://www.tubebooks.org/Books/rider_inside.pdf

Lawrence.