-----Ursprungligt meddelande-----
Från: Lennart M [mailto:lennart.michaelsson@telia.com]
Skickat: den 6 maj 2012 19:43
Till: 'Guy Olinger K2AV'
Ämne: Topband: Monopole Radiation Patterns, takeoff angles
"
Dark matter, dark energy...we're having a VERY hard time making our
equations stretch around the universe. Radio propagation, what goes on in
space between two distanced physical occurrences is part of that "stuff"
out there they can't get under control."K2AV""
Well guys!
I still recall having two different MW verticals erected in the 1970's. (
for ship to shore traffic). They were exactly the the same layout. 30.5 m
high with a wide cage and a 120 x 100 m ground wire counterpoise. They had a
broad band filter making the antennas useful for 1.7-3-5 MHZ. Both antennas
were located very close to sea. One was close (50 m) to the Streats
separating Sweden from Denmark and the other one was on the east coast of
"Skane" the south part of Sweden. We actually measured the field strength
from each of the antennas and found they were equal.
Never the less I did some "Ham radio" from both positions and found out that
the one being closer to Denmark worked out consistently better than the one
on on the east coast of Skane.
My "Helmer" in commercial antennas, buried long ago, told me that the
difference might be due to the Geomagnetic field between those two
positions. We checked that out and there was a difference!
He might be right, but the only correct answer is: Pick your QTH, invest
money in ground system for your antennas antenna and invest in a good rx
antenna system.
Easily said... Difficult for most of us!
73
Len
SM/BIC
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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