[Milsurplus] 211 Tube Note

[Richard Brunner]

Re:
> The 7.5 amps is combined plate and grid current.
> In triodes, the simplest and safest way to meter the tube is to measure 
> the
> cathode current, which is the combined plate and grid current. No HV needs
> to be fed into the meter this way. Normally, the more grid current, the
> higher the plate current.

7.5 amps baloney.  The filament is rated 10 volts at 3 1/4 amps, max plate 
current 150 ma, max grid current 50 ma, 18-35 ma typical.  Yes, connect the 
plate current meter from the filament transformer center-tap to ground, and 
connect the grid return to the plus side of the plate meter, (not ground) 
thus separating plate and grid currents, then the "plate" meter only 
measures plate current.  Use a separate meter to measure grid current, which 
you want to do anyway.

Richard, AA1P