VE7BS says
> He answered "The only thing you can say for
>sure is that is will probably be somewhat different from the way it
went up."
I believe that conventional wisdom says VLF signals are generally
vertically polarised, as are ground wave signal over conducting ground.
A signal coming off the ionosphere isn't travelling, I guess, over the
ground in the same way as either ground wave or VLF - I believe the
conventional wisdom says that the wavefront is tilted as it travels over
the ground, as well as being attenuated. That's how the Beverage picks
up a vertically polarised signal. The tuned loop when vertical also
picks up a vertically polarised signal.
Now given these postulates, can anyone answer the following:
What is the predominant polarisation of static? Is it different between
close in static and thunderstorm hundreds/thousands of miles away?
Is man made noise mainly vertically polarised at 160? If so, what is
'mainly'? 50%? 90%?
What is the best horizontally polarised receive antenna with good noise
rejection for local electrical noise? And the best for a small (<100
foot) plot?
In QST about 2 or 3 years ago, there was a low noise horizontal loop
antenna, which was, as I remember it, a small Alford loop. I got no joy
with it, but as Carl, KM1H, said the other day
"IMO we all need more info on antennas in real world situations."
And as locations are different, it doesn't always follow that what works
in one location will work as well in another.
73 Peter G3RZP
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