To: <topband@contesting.com>
> Date: Tue, 17 Feb 1998 18:22:09 -0500 (EST)
> 160 (de G3XTT)
> The static, however, is
> continuous, not crashes, and comes from all round the compass. We continue
> to work on various rx
> antennas, but most suggestions seem to assume we have local noise, and
> that's not actually the case.
> Has anyone out there solved this kind of problem?
I don't know how to forward this to G3XXR, but the ONLY cure for
noise like this is directivity in the antenna (in other words, by
focusing the antenna only in the direction they intend to receive).
The null has to be VERY wide to make any improvement, and no simple
small antenna offers a wide null.
The only realistic cure is a Beverage, since even an EWE has a
very narrow null. A Beverage will work very well even over salt water
IF it is high enough above ground (~3 meters or more), properly
terminated, and installed with fairly good grounds at each end
Static is an ELECTROMAGNETIC signal just like our transmitters. An
antenna (even a magical "magnetic" loop) knows no difference between
propagated QRN and "good signals".
If the Beverage doesn't help, and you can't install a large phased
array, your likely just stuck. A smaller antenna won't be any better
if noise comes from many directions, since the null area is always
smaller and you need a BIG null area.
Good luck!!
73, Tom W8JI
w8ji.tom@MCIONE.com
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