Bruce,
I believe that is extremely possible. I have witnessed the same exact thing
here in northern lower MI where we live in giant sandbox. I have especially
noticed changes in feed point impedance on RX antennas during the winter months
when the soils are generally frozen versus the mid summer with lower moisture
content.
I have even had this issue with some transmit verticals.....drove me nuts for a
while at my last QTH with my 160 inv L where I didn't have a huge radial
field.....the feed point impedance would drift between seasons....
One of my next projects is actually going to be setting up a data logger to
monitor the soil resistivity throughout the year....Inquiring minds NEED to
know!
DaveKB8NNU
From: K1FZ-Bruce <k1fz@myfairpoint.net>
To: Topband <topband@contesting.com>
Sent: Tuesday, March 29, 2016 10:16 PM
Subject: Topband: Ground conductivity
Done my yearly spring maintenance of my SE single wire Beverage antenna. With
poor soil, It typically is best with a 350 ohm matching transformer and a 330
to 350 ohm termination resistor.
But this year it is best with a 450 ohm matching transformer and 450 ohm
termination resistor.
A higher value typically means more conductive soil. I do not have the time, or
equipment to make accurate RF ground conductivity measurements now.
But got wondering where Maine gets the WX after it passes over most of the
lower 48 states, With climate change and the highest carbon content in the
air. Could rain be causing my soil to be more conductive ?.
Has anyone else noticed anything like this ?
73
Bruce-K1FZ
PS: Delta,Pennant, Flag antenna notes has a new address
www.qsl.net/k1fz/flag_antennas.html
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