Hi Peter,
> What we heard during the contest was genuinely poor signals from a number
> of stations, not receiver overload !
I generally turn my rig off during SSB contests, or go move to the
low end of the bands far away from the SSB operators.
> I used up to 30 db of attenuation while listening and the distorsion and
> splatter was still there. Some had distorsion to the extent where I could
> hardly hear what the guy was saying and this had nothing to do with my
> receiver being overloaded.
Local noise level at the receiving site is also a factor.
Many operators will ask a station with S-9 background noise to
"tune around and listen to them". They will, almost without
exception, report back "you are 20 over nine and sound very clean
at my house".
To simulate typical on the air splatter tests like this, you can set
the baseline of your analyzer to 20 dB below PEP reference. Even
a class C PA makes a dandy SSB linear when tested this way.
Of course, if your background noise is S1 or so (like mine is on
most bands most days) you could hear splatter that is 50 dB down
or more.
Then only the KWM-2's and 32S3's sound really good, and would
get a flattering report.
73, Tom W8JI
w8ji@contesting.com
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