> They put up two top-loaded 60ft verticals for a 160m array. One was
> near large trees and one wasn't. The one that was near trees had an
> input impedance of around 75 ohms, and the one not near any trees had an
> input impedance of 37 ohms.
That's a big change! I'd like a copy of that article Carl.
The element of my four-square that are in the open are around 34
ohms. The one near a very large Pecan tree (maybe 80 feet tall,
and quite bushed out reaching within ten feet of the antenna) is 36
ohms.
However, that says absolutely nothing about the amount of loss. I
have no idea if the resistance increase is do to loss or a change in
current distribution. The only way I'd know for sure if it added loss
is to remove the tree while measuring FS at a fixed distance and
direction in line with the tree.
73, Tom W8JI
W8JI@contesting.com
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