> I wouldn't say that the screen supply in the 91/99B is well regulated
> (only zeners) so that amp doesn't necessarily show us the best IMD
> performance the 4CX800 is capable of.
Many amps have less regulation than that Ian!
My point is that by the time you build a good system that rivals GG
triodes for IMD, it costs more money that the triode amp.
Unless you add negative feedback in the cathode of the tetrode and
use a well-regulated supply, they aren't so clean.
> Even so, I think it's being far too sweeping to imply that all tetrodes
> have worse IMD performance than (all) triodes. There are far too many
> other factors in the design and operation of an amplifier.
Of course. Some tetrodes are very clean, but then are some
triodes.
> There's no doubt that tetrode amps are much less "plug-and-play" than
> triodes. It's easier to get things wrong, either at the design stage or in
> operation. But if you do get everything right, a tetrode can give good IMD
> performance.
The key is "getting everything right". Many hams can't tune a GG
triode properly, I'd hate to see what they sound like with the screen
in current limiting!
> >you still haven't solved the bandswitch problem.
> >
> Which all tube amps share alike.
Exactly. That problem remains the same.
73, Tom W8JI
w8ji@contesting.com
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