[Amps] FW: Testing amp with no air flow

[Theo Bellamy]

Larry wrote:

"I've tested the filament on the 3cpx5000a7 without air flow but with
filament running less than 15 seconds."


I have a friend who built a YC-156 amp. It was all manual - separate toggle
switches for everything, including the blower. He let a visiting ham operate
his station one night and went to bed. The visitor got done and turned
everything off except the filaments. The tube sat there the rest of the
night and into the next morning with the filament lit and no air. That tube
is still working fine today, nearly fifteen years later.

I wouldn't try that with an 8877 however!

83 - Theo K4MO