>
>re the ongoing debate,
>
>> >Whenever grid current
>> >flows in a grid driven amplifier, linearity is compromised.
>>
>> Rich, you keep saying that in such sweeping, all-inclusive terms.
>> You may believe it most sincerely, but that still doesn't make it true.
>
>my unsolicited $0.02 worth is... there are tubes where even a teensy
>bit of grid current will result in compromised linearity. there are
>tubes where a fair amount of grid current can be drawn, with no
>compromise.
Name a tube where a fair amount of grid current can be drawn in
common-cathode configuration with no compromise in linearity, George.
> it ain't grid current that's the defining
>characteristic! it's the linearity! the "transfer characteristic"
>should be a straight line. if it bends, then it ain't linear.
Agreed. With grid current, the line bends.
>with many modern tetrodes, even those with handles, there is a serious
>bend that occurs just about at 0 volts on the grid.
For an 8171/4cx10000D, the transfer characteristics don't really get the
bends until the grid voltage reaches roughly +15v.
>...snip... if the 3d and
>higher order products are legal, then maybe it's not so bad.
>
The legal limit on splatter inside a ham band is essentially that the
splatter can not extend outside the ham band.
Rich---
R. L. Measures, 805-386-3734, AG6K
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