> From: Rich Measures <measures@vc.net>Rich,
We've been over this a hundred times.
You wrongly insist you can simply multiply the RMS drive voltage
against the indicated meter current.
> - 100mA equates to about 2.7w.
That's nonsense.
We have no idea what the grid dissipation is unless we know the
driving voltage AND waveshape of the grid current at the particular
operating point. Since it is under a condition of mistuning, it is
not in Eimac's data.
Eimac does say (as I-- and others--- have pointed out to Rich several
times) grid dissipation can be estimated by taking the grid cathode
PEAK voltage and multiplying it times the indicated grid current.
This calculation is approximately true for most operating conditions,
as long as we remember the peak voltage is not the voltage under
normal tuning conditions. As the loading is lightened, the peak
grid / cathode voltage increases in a grounded grid amp.
Short of a direct measurement, a more accurate method is available
using software supplied by Eimac, or a program called "triode". Using
the software will convince anyone (except Rich) tubes can be
easily damaged by improper tuning.
73, Tom W8JI
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