W5UN wrote:
>>The 160 system uses 4
radials per antenna, and these are 20 feet high and parallel to the ground.
John, ON4UN, claims I now have a great dummy load on 160, hi. But its
working for me.
Soil conditions undoubtedly have something to do with it. I live in
Northeast Texas, and we have hardwood trees and grazing land here with a
lot of iron in our red clay like soil, together with sand (I'm about 40
miles south of the Red river, guess where it got its name). W7IUV has had
just the opposite results from mine as far as antenna performance is
concerned. Larry claims his system is a poor performer. He is in western
Washington with desert like soil conditions.<<
Yes, I also think it has to do a lot with the RF quality of the ground
underneath.
I seem to remember, when modeling various verticals over poor ground vs. sea
water and vicinity, fewer elevated radials work much better over good ground.
Less loss between the radiator and radial counterpoise, better coupling between
radial and good ground and forming far field pattern.
Back in Toronto (clay soil) I had lousy results with verticals and limited
radials (46' wide lot).
In NJ QTH (high water table, spring across the road) verticals with few
elevated radials seem to work very well. I had 160 balloon vertical with four
30 ft elevated 1/4 wl. radials work very well, same at Cape Hatterras with 10m
elevated radial verticals and 4 squares.
Even Inverted -^- at 30 ft in a tree here, seem to work as "bottom loaded, top
fed, half vertical" quite well.
At C6AYB with half sloper from the 9th floor hotel balcony at the shore, it was
a "killer" antenna.
W8LRL's 3/8 vertical with 360 3/8 radials at his QTH seems to perform as good
as 4 sq at low angles.
We will run some tests between his "standard" and various configurations at our
Ocean Gate N2EE QTH.
I am looking forward to play with some designs there, taking advantage of salty
marshes.
It really depends on the soil quality, if it is good to ideal, fewer elevated
radials seem to do very well and far field low angle is enhanced. In poor soil
many and long radials are necessary for good vertical arrays performance.
Yuri Blanarovich, K3BU
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