Since I wasn't in the contest (they wouldn't take my NA log file from
last year), I decided to spend some time with an analyzer in the
shack looking at signals.
I identified 11 stations with strong spurious signals. (Not counting
excessive clicks as spurious, since there were dozens of clicky
signals) Some of the spurious frequencies were as low 1.723 MHz, and
as high as 2.6MHz!
If anyone had reports of a spurious signal from anyone else, please e-
mail me!! I want to write a summary of the equipment (no names
mentioned). It is important to learn exactly what causes the spurs,
and how to avoid them, especially since some of this stuff is out of
band.
Of responses so far.... MOST do not appear to be RX antenna overload
related! Three have a common "thread", they have amplifiers and T-
network antenna tuners. When they switch tuners off the spurs seem to
disappear! This very well may be a design problem with certain
amplifiers where certain load impedances cause the PA to become
unstable.
73, Tom W8JI
W8JI@contesting.com
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