[AMPS] Tuning the 91b

[km1h @ juno.com]

I hit delete by mistake but here goes.....

The proper way to tune that amp is to:
 - Set the idling current as per the manual by adjusting the bias supply
voltage. 
- Use the screen current meter as you would a grid meter in a GG amp.
Adjust the Tune control for a current peak and the Load control to full
RF output AND safe screen current. 
- As with a GG amp, increase the loading just a bit past maximum output
for best IMD.

Adjusting the screen voltage and having a fixed bias is a bunch of
hogwash in that amp or any other commercial ham tetrode that I am
familiar with. Show me an adjustable screen voltage pot.
If you modified the amp for that the warranty would be void.   

73....Carl   KM1H

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