At 11:34 PM 11/4/2006, Rick Karlquist wrote:
> > I would agree that there's a lot of manmade noise about, it's the
> > assertion that it's *predominantly vertically polarized* that I'm
> > curious about.
>
>Local manmade noise may start out randomly polarized. However, only
>the vertically polarized component can propagate by ground wave.
>This is well known physics. The horizontal component is rapidly
>attenuated with distance.
Excellent point.. OK.. So, given that surface wave signals MUST be
vertically polarized, and that manmade noise is going to be
propagating by surface wave, by the time it gets to you, it will be
vertical. It's not that the source of the noise is polarized, it's
that the likely propagation path is a polarization filter.
I would assume, then, that this is for manmade noise coming from some
distance away (for instance, if my neighbor 100 ft away is radiating
noise, it's a line of sight sort of path and there's no real
attenuation of the Hpol component.
Here is where the elevated antenna is going to help.(regardless of
the antenna polarization).. it's farther from the noise sources that
are in the "near field"
>Rick N6RK
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