KG4JJH DUAL-BAND MOXON
UPDATE:
Allen's story was published in the August 2005
QST. Allen has kindly made his eznec files
and the full construction and parts list pdf
file available to the MoxonAntennaProject website.
You can download these files which have
been zipped into a single archive. DOWNLOAD.
Since
the beginning of the Moxon Antenna Project website,
interest in multi-band moxon designs has been
high. Cebik has a section on "nested"
moxon designs, however, he points out that any
design has certain trade-offs. There are
several multi band designs shown on this website.
Recently,
Allen Baker, KG4JJH (who's Black Widow 15 meter
moxon was publish in QST) has completed a dual
band 17/12 meter moxon shown above. He
has submitted a write up of the antenna complete
with construction notes to QST which was accepted
this past July. No word on a publishing
date yet. However, he has graciously provided
some data for us:
"This
antenna is more rugged than the Black Widow
and weighs 15 lbs, so it's not a good candidate
for most push-up painter poles. I'm currently
using a surplus military mast at 35 feet. The
antenna is completely weatherproof and consists
of fiberglass tubing, aluminum plate, stainless
steel hardware, #14 Flexweave wire, and pvc.
Both band elements are at the same elevation
and are fed with one 50 ohm feed line. The measured
SWR for both bands is less than 1.4:1. My first
17m contact was Curacao on 5w ssb!. These
EZNEC azimuth plots will give people an idea
of the antenna's characteristics. The
plots are color coded: blue is the bottom,
black is the middle, and green is the top of
each band."
According
to these plots, the dual-bander has pretty decent
gain (10.94dbi) and an average of 24db
front to back for both bands. Allen
will be providing more information as soon as
his QST piece is published. In the meantime,
if you have questions about the construction,
you may email Allen at awbaker@charter.net
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