>
>On Sat, 6 Sep 97 11:10:02 -0800 Rich Measures <measures@vc.net> writes:
>>1.. Grid current -/- make the bias V adjustable, and set it for
>>virtually zero grid current with max. drive applied. / Using the
>>bias V adj. to increase ZSAC results in grid current, and distortion. The
best way
>>to increase ZSAC is to increase screen V, as long as you do not exceed
>>the max. rating.
>
>Here we go again! HORSEFEATHERS Rich. Lets get off the theoretical and
>into the living world.
Decreasing the grid bias V to a value lower than the peak RF driving
voltage causes grid current to flow. Does Svetlana say that it's kosher
to run grid current on the specification sheets, Carl? OTOH, increasing
the bias V is an appropriate means of reducing ZSAC if need be.
>Use a fixed voltage screen supply and vary the bias for proper idle
>current. It is easy and repeatable AND with modern tubes the IMD will
>still be below the garbage from most riceboxes.
Not if one runs more than a tiny amount of grid current in a grid-driven
was-linear amplifier.
>I am sure I will get grief from a few but the real object here is to
>produce RF with a decent and acceptable level of crud.
According to part 97, any and all splatter inside the ham band is
acceptable to the FCC.
Rich---
R. L. Measures, 805-386-3734, AG6K
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