Here's some info of interest regarding antennas and trees from K9LA
that may have already been discussed:
http://mysite.verizon.net/k9la/sitebuildercontent/sitebuilderfiles/
low-band-antennas-and-trees.pdf
In Fairbanks, my 160M Inv-L goes up 80' and out 56.5' with a SWR of
1.3:1(about 38 ohms) is resonant @ 1.825 mHz with three 128.6'
resonant radials of #14 THHN elevated at least 15' over poor soil on
a 120' sq. city lot. These values did not change after freeze-up, so
I assume the tree's influence (they're White Spruce) also didn't vary
much. However, when using 120 ground-mounted radials in the past at
my other shack out in the woods on a similar length/design antenna, I
would note a small shift in resonant frequency and SWR as the ground
and trees froze. I assumed that was due to earth conductivity
changing below the ground plane and horizontal portion of the L-
element. When the wind blew hard, and the trees wobbled, the SWR
would also walk around a bit until the wire inevitably broke (:-(
73 Gary NL7Y in Fairbanks
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