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Les
Moxon, G6XN originally designed the Moxon Rectangle based upon
a design by Fred Caton, VK2ABQ. L.B. Cebik,
W4RNL optimized a wire version of the Moxon. The Moxon can
be visualized as a 2-element yagi with the element tips bent towards
one another. The tips are separated by an insulator creating a gap
which is mostly responsible for the directive pattern unique to
the Moxon.
The Moxon is a directional antenna
system that is gaining in popularity because it offers three very
distinct advantages over a typical two element Yagi:
- Small in physical size.
The Moxon can be built using a very lightweight structure and
wire elements, which will fit into a footprint about two thirds the area required for a conventional beam. You can see
by the measurements above that a 20 meter Moxon is only 25 by
9 feet. Being a very light structure, typically made
from wire and lightweight spreaders, it can easily be mast mounted
on a lightweight pole, hoisted up in a tree from an overhanging
branch, or turned vertically and ground mounted! As such
it also makes an excellent field antenna.
- Outstanding front to back ratio.
The Moxon's front-to-back
ratio models at greater than 30dB! Moreover, close-gap coupling
enables the Moxon's enhanced performance to be realized at lower
elevation heights of only 1/2 wavelength. As seen below,
the Moxon exhibits a broad forward area combined with superior
front to back.
- The Moxon is a 50
ohm antenna,
generating a near perfect 1:1
swr without requiring any additional matching devices. It is
also quite broadbanded allowing for effective full band coverage.
The Moxon antenna can provide hams with
an excellent antenna system that is easy to homebrew and usually
does not require any adjustment if made according to the dimensions
specified by software
that is available on this website. A typical Moxon rectangle
can be built in a few hours, using X or H type of spreaders made
from bamboo, fiberglass, pvc or a variety of other materials.
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