I wanted to solicit some feedback on a wire antenna I read about.
I used to have more space, with a 40' Rohn 25 tower bracketed to a two
story house, a TH3 tribander at 42', and inverted-v wires on 40/80.
Moved several years ago. I now live on smaller suburban lot 80'X130', one
story house, three 30'-40' trees in front yard. Pool and concrete occupy
backyard space. Also of note, there are some utility telephone poles
12' behind back fence about 40' tall.
Since I moved here, I have only put up a pair of dipoles (20M/40M) in trees
about 25' in height. Briefly, I balanced TH3 on chimney above roof
(less than 20') last fall during November, but with limited success. Some
high SWR and TVI resulted; maybe due to low height, presence of many
phone and utility wires in attic beneath antenna, feedline running across
roof, and poor station ground (at the time). Not exactly sure.
With more demanding job (i.e. travel) and family, I have not operated
much at all last several years; but anxious to restart. I enjoy contesting,
but desire 5 or 6 band coverage. Many of my expert friends suggest NOT
buying a vertical -- instead, they recommend dipoles (or TH3 on roof or
even a 20' pole) would be better.
While looking for a minimum-cost option multiband antennas, I found article
in the 1988 ARRL Antenna Book in Chapter 5 on Loop Antennas entitled "Loop
Skywire." The article references 1985 QST information from Dave Fischer,
W0MHS. It describes what sounds like a very effective antenna. It is a
horizontal loop, multi-band (3.5-28Mhz), coax fed (no balun nor special
matching was recommended), 272' square, and supposedly very effective if
operated at 40' in height above ground. For about $100, I can use some
available materials to assemble guyed poles with trees and put up such an
antenna at a height between 30' and 35' above ground. This would physically
be situated above and just outside the outline dimensions of my house (except
garage). The antenna would also be about 25'-30' north of utility poles
behind my lot.
I realize this will be a poor second to any tower plus yagi antenna station;
yet it sounds like a great improvement over dipoles, relatively easy to
assemble, and not overly obtrusive (would be largely undetectable view from
street in front, but clearly visible from sides and rear). Has anyone had
any experience with or knowledge of others about such an antenna? I would
appreciate feedback, suggestions, thoughts about RFI, TVI, SWR to be expected?
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