[Amps] Henry 2K-3

Jim Valdes jvaldes at whoi.edu
Fri Mar 11 11:28:09 PST 2011


Hi - resurrecting an old 2K-3. Have the power supply at 2.8-3 k and have 
baked the tubes w/o HV to degas.
I found a reference to loading which suggests there should be about 800 
ma plate current at 250 ma grid current at full output. I can generate 
about 250 ma on the grid but the max I can get on the plate is about 500 
ma. and about 900 watts output (40 & 20m). So, 2800 x .5 = 1400 watts 
input. 900/1400 = 64% efficiency. Is this about right with 100w drive or 
should I be looking for 800 ma? 500 ma seems low for a pair of 3-500s- 
soft tubes??
Thanks,
Jim



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