[Amps] Ameritron Amps

[Peter Chadwick]

Rich said:
>As I understand it, the recipe is similar to Pyrex in that it uses  
boron as a fluxing agent instead of lead.<

Going back a few years, I remember reading that the 24G, 35T  and 35TG had envelopes of  something called 'Nonex' glass, which had a greenish tinge. Those tubes all had tantalum anodes which were bright yellow at full whack, and the 24G and 35TG were used up into the VHF region - 120MHz. the 24G was used in the BC640 ground station VHF tx, which somebody told me, was so bad for TVI it caused trouble even when switched off! So any ideas what 'Nonex' glass was?
I could see the glass softening around the anode seal, just because of the conduction up the connecting stem, especially if the glass was lower melting point and the cooling inadequate.
73
Peter G3RZP