> The prevailing theory (from a CCIR bulletin whose nomenclature doesn't
come
> to me right now) is that "static" on HF is primarily caused by
> thunderstorms in the tropics, propagated ionospherically just like
desired
> signals. The CCIR bulletin makes comment that although in some localized
> instances one can avoid noise spots using directivity (i.e., use an
antenna
> of sufficient *azimuthal* directivity to reject azimuths of high
> noise/thunderstorm concentration and therefore improve S/N), experiments
> seem to indicate that tropical noise appears isotropic...coming from all
> directions.
What about the use of a device like the MFJ-1026 which allows one to use a
second antenna to capture, isolate, and remove (null out) specific noise
sources.
Does this sort of concept help to significantly lower to S/N argument
against
the value of improved RX gain from an antenna?
73, DavidC K1YP
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