COLIN LAMB wrote:
Finally Eimac called him and learned
that the chap was turning the tube filaments off between transmissions and
turning them on immediately before each transmission.

So, do not use either tube for break in cw by keying the filament.

73, Colin K7FM




I have to wonder what the keying waveform might have looked like.
Probably added a unique sound to his signal. Something like a modified
banana-boat swing, for lack of a better description?
de K3HVG