Generally speaking, the key clicks and the general hash most of us call phase
noise (It's actually a mix of phase noise, partition noise, shot noise, Johnson
noise, artifacts of multiple mixing, and who knows what else, with phase noise
usually predominating) is worse on 20 than 40; and given comparable antennas
it's still worse on 15 and 10.
However, looking at some of the worst offenders spectrums it appears the higher
ambient noise levels on the lower bands tends to cover up spurious emissions.
That is certainly true here, where my FS meter says I have up to 105
microvolts of background noise on 160, 65 on 75, and 35 microvolts on 40 under
dead band conditions. That's about three times the maximum background noise
level I have at the farm. One of the reasons the new ham shack floor should be
poured tomorrow - and one of the reasons my country total on the lower bands is
abysmal.
It would be nice if the new emissions rules cleaned up the racket. But I'm
afraid only time and perhaps peer pressure will remove the offending
transmitters. We certainly cannot expect the gummitup to do it for us.
At any rate, the powers that be have taken note of the problem. If taking note
turns out to be another case of laboring mightily to bring forth a mouse that
will be regrettable. But we shall see and hope for the best.
73 Pete Allen AC5E
--
Never squat with your spurs on
>W4BQF sez: I never really noticed key clicks much on 40m except
> on rare occasions. But I'm quickly finding a very different story on
> 20m...seems like about 80% of the CW signals on 20m are accompanied with
> clicks. Most descriptions of their rigs are the top two foreign brands.
>
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