In a message dated 10/24/01 1:14:01 PM Central Daylight Time, jerry@rchco.com
writes:
> The arrl ant handbook suggests a horizontal loop is a better antenna
> than a dipole in a manmade noisy environment... before I try one at my
> in city noisy environment, does anyone have experience with these?
> jerry
> k7xx
>
===== =====
Evening Jerry,
I've used a number of different closed wire loops over the past fifteen years
or so. They've varied in size from around 250' to the present one being used
which is a little over 1100' in length. I've always used about the same
method to feed them - - - ladder line to a 4:1 balun mounted somewhere under
the eves of the house, and then a relatively short piece of coax going from
the balun to the tuner or transceiver.
Other than the present one, all of the loops I've used were within a city
environment (Hinsdale, Illinois) - - - read> lots of man-made noise. For
whatever my personal experience is worth, they were ALWAYS considerably
quieter than other antennas - - - HF verticals, yagis, and dipoles.
We moved to the country (Elburn, Illinois) about five years ago, and the
first antenna I put up was the presently-used 1100' loop. Thanks to the help
of a spinning reel mounted on a bow, I put up about a dozen or so halyards
and then pulled the wire up into a bunch of ancient Oaks, into the form of a
rather odd-shaped, closed loop. There's about 150' of 450 Ohm ladderline
running from the loop to the house.
The loop is used mostly as a receive antenna on 80 & 160, and it is very
quiet compared to the other antennas. I have two towers, a 60' Rohn 25, and
a 85' Rohn 45 and they are shunt fed for 80 & 160. I usually transmit on one
of the verticals and receive on the loop, although many times, have listened
on both the loop and one of the verticals simultaneously with very favorable
results - - - sometimes taming a lot of the QSB encountered.
Surprisingly, the loop is a pretty good DX antenna on the higher bands. I
believe that as you go up in frequency, the launch angle must progressively
diminish. Actually, even on 40, I've found that the loop will receive as
good or better signal reports as two elements at around 87'. I suppose it
isn't too hard to believe considering that the loop is well over eight
wavelengths on 40.
Hope some of the comments are of some help, and that you're able to try one
of the magic HF loops in the near future.
Best regards,
Ron Hensel, K9ZE
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