Get that bottom run at least 5' up from the ground and it will work much
better. Do you have any trees to string the #12 wire in??? I have a LF loop
with the top run at 60 to 70'. The bottom run is adjustable for testing
purposes. It is strung over two big trees per Bill Ashlock's advise. I call
it my Ashlock loop.
73's,
Mike>WE0H
http://www.geocities.com/we0h/lf.html
-----Original Message-----
From: [email protected] [mailto:[email protected]]On Behalf
Of PC
Sent: Tuesday, April 09, 2002 11:05 AM
To: [email protected]
Subject: Re: LF: Ground loss diffferences between loops and verticals
Hello Jim and the group,
Thanks for responding! I will read your email again beacause it addresses
exactly what I was looking for as far as the ground questions are concerned.
As far as the performance of my antenna it seem in this as in many other
things I am always looking for a complex answer and continue to overlook the
obvious. This loop is located about 6 feet away from the 130 tower with its
18 guy wires.
Bill Ashlock (WA) along with others pointed out the tower and its massive
array of guy wires would have very detrimental effect on the pattern, "Q",
feedpoint impedance, etc.
So I took down the antenna which again weighs 60 lbs and put up a #12 AWG
wire in its place. Much more managable.
Same location, even higherfeedpoint impedance as I expected and a lot less
capacitance to resonate, also expected.
Next step was move the antenna away from the tower by 25 feet. This made a
big difference. To achieve resonance I had to add more capacitance and I
had to add 2 turns to the primary of the matching transformer indicating
lower feedpoint impedance.
So tonight I will move it even farther away and get the feed poit above the
ground, it is only 6" high right now.
Lesson learned..... Do not overlook the obvious!!!
Thank again Jim.
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