[600MRG] ground ++trees

[Pat Hamel]

Rudy has the land, knowledge, instrumentation and writing ability to measure
the ground losses.

For my two cents, I have fairly well documented in my logs the effect of
close-in nearby (six feet away at the bottom and smaller ones growing
beneath the top load) trees on my vertical antenna performance.

I am on a small 120' x 120' city lot and used trees to support my inverted
"L" antenna. Here on the gulf coast we almost never get freezing days, but
it happens in mid-February during part of the sunspot cycle.
When the weather freezes for a couple days, apparently the sap in the outer
layer of the tree stops being a saturated liquid with lots of available
ions. This seems to reduce the loss the tree presents as a long load
resistor parallel to the antenna wire. I don't have a way to measure the
effect of freezing the mushy ground around the trees separately.

In my case I used real antenna current meters and the W5JGV remote meter and
could see a difference. I was also able to get and give better reports in
daily QSOs with XGR/6 in New York.
As the "invasive species" trees grew under my antenna across the fence, I
believe that my actual radiated power was reduced.

Conclusion: (tongue-in-cheek) a chain saw may help optimize your 630 meter
antenna - after you find the lossless skyhook.
73,
Pat /6



-----Original Message-----
From: 600MRG [mailto:600mrg-bounces at w7ekb.com] On Behalf Of Rudy Severns
Sent: Friday, February 06, 2015 4:52 PM
To: 'D.J.J. Ring, Jr.'
Cc: 600MRG
Subject: Re: [600MRG] ground

It's not surprising your antenna current wanders around as the seasons
change.  My antenna has 128, 150' radials and a top hat 240' in diameter but
I still see significant changes in tuning even during the winter when the
soil characteristics wander around only a factor of two or so 
SNIP