Well, partition noise is not a major contributor to TX noise. But it's still
there - along with all the other classic noise sources I learned about between
WWII and the "Korean Police Action," as well as some that weren't dreamed of
even thirty years ago. And a few noise makers have been reduced - Johnson noise
in particular is generally less than it was in hollow state devices.
The major contributor to spurious emissions seem to be phase noise and ALC
circuits that cannot react quickly enough to limit the power output to nominal
or reasonable power output without adding severe distortion products to the RF
output. Both of which should have been taken care of in the initial design
stages.
Of course, CW rise and fall time can contribute to key clicks. Since I have no
ambitions to be a high speed CW op I keep the Orion set at 6 ms which seems to
satisfy the guys across town and raise no complaints on the air. If I were
slower I would slow rise time and fall times down and if I were faster I would
be forced to decrease it.
That's just one of those things. High speed CW takes more bandwidth, and the
faster transition that's necessary for shorter characters may create clicks. As
long as they aren't the extreme sort covering several kc, kHz, I hear so often
from the "bottom two" of the "big three" I don't complain a lot. Mutter under
my breath, maybe!
73 Pete Allen AC5E
--
Never squat with your spurs on
> Thanks for the info regarding paritition noise as it applies to solid state
> devices I was under the false impression that partition noise was generated
> only by boat anchors! Since Ten Tec is primarily solid state (except for
> amps) their equipment was partition noise free.
>
> 73, Jim
>
>
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