A few years back we had drenching rains for weeks and the local club used my
place for Field Day because of my elevated yard and driveways... I put up a
160 meter horizontal loop at ~35 feet, out in the corn field in knee deep
water and mud, and also put a reflector on wood stakes about 2 feet off the
ground directly underneath the driven loop... The guys used a tuner for all
band operation, with window line... We felt that it was an effective antenna
installation for FD, and certainly simpler than the multi antenna array we
normal put up... We noted that we could run a frequency at will with just
the single loop... Only on 20 did we notice definite areas of the country we
were missing... We talked about adding some other wires but saw that the
operators were staying busy anyway, so why bother...
About 45 minutes before the contest ended I decided to get started on tear
down... I went out in the field and and untwisted the two bare ends of the
reflector wire (it bit the heck out of me as they were keying the
transmitter) and began rolling it up in a coil... I had been out there maybe
5 minutes when two of the guys came out and said, "Did you change something?
We lost our run frequency."
Seems that disrupting the reflector wire dropped the signal on 40 meters
enough that another station muscled it's way in and took over...
Denny
----- Original Message -----
From: "Stuart Rohre" <rohre@arlut.utexas.edu>
To: <tentec@contesting.com>
Sent: Thursday, January 18, 2001 1:36 PM
Subject: [TenTec] Sorry about the copying of the other message, further loop
comment
>
> Sorry, I did not mean to also copy the original message and add to list
> bytes.
>
> But, I should say we tried the full wave plus loop based on a memeber's
home
> experience, then we modeled it after field day and that confirmed our
> getting out at both low angles and high angles with only 20 foot high loop
> over a football field, over average ground in the model. The loop was a
> delta shape and longer east west than north south, just because of where
> available supports were located. The feed was on west corner, and was
450
> ohm ladder line to Dentron super tuner balun and transmatch. Very easy to
> make a tuner chart and change bands by presetting the transmatch dials, it
> is a Tee match circuit. I was not a believer in low loops before, but
sure
> changed my tune!
> 73,
> Stuart K5KVH
>
>
>
> --
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> Submissions: tentec@contesting.com
> Administrative requests: tentec-REQUEST@contesting.com
> Problems: owner-tentec@contesting.com
>
--
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