Insulated Wire � Complete with 98
foot RG-8X Feedline
You can hang it in trees or lay it on your roof
Needs no tuner - Ideal for QRP
500 Watt Rated � 160/80 M is
264 ft, 80-10 M is 132 ft, 40-10 M 66 ft
Off center feed ⅓ on one side and ⅔
of the other side of the feedpoint
Resonant antennas are inherently efficient radiators, not only on their
lowest band of resonance, but on harmonic bands as well. The problem is to find a way to
couple energy into the antenna with a good impedance match to the transmitter.
To create the Windom we apply energy to the antenna at a point where
the impedance is the same on many bands (off center feed). Our broadband devices inserted
there allow the antenna to be fed with 50 foot + coaxial cable. VSWRs on the covered bands
are typically well under 2:1, easily within the range of solid state transceivers designed
for 50 ohm loads. Equally important, of center feed gives double the bandwidth of a
standard dipole, making it useful for many MARS, CAP, and RACES frequencies as well.
Construction. Our basic Windom is 132 feet long and provides no-tune coverage of the 80,
40, 20, 17, 12, & 10 meter amateur radio bands. With an appropriate antenna tuner it
may be used on 160, 75, 30 and 15 meters as well. Our Windom is made of highly flexible,
kinkproof, insulated #14 41 strand antenna wire. Its mating feedline measures 98 ft and
includes a unique isolation choke to block currents on the feedline. The antenna is
factory assembled, weather sealed, and pre-tuned for best Multi-band performance. When
shipped it is ready to use. Installation.
Install it at 20 feet or greater and in a straight line. Support ends
with non conductive double Dacron or Nylon line. Take advantage of trees as supports. Support
feedpoint if possible. Limit tension at antenna ends to 60 pounds and allow 5-ft sag if
the feedpoint is not supported. If straight-line installation is not possible, install as
inverted-V. Keep antenna as horizontal as possible to preserve efficient radiation on
upper bands. If space is limited, place insulators in from
the ends a few feet and let ends hang free.
As much as 20 feet may be allowed to hang down at either end.
Radiation on Pattern. At installation heights below 50 feet, radiation
is essentially omni-directional and at high angles for frequencies below 7 MHz. Above 7 MHz
radiation concentrates in four major lobes diagonal to the wire and taking off at low
angles. The higher the frequency, and the higher the antenna, the lower the angle of
take-off. Expect solid coverage in all directions on 80 and 40 meters, and increasing
distance with an enlarging local skip zone for successively higher bands. For most
effective communication with locations beyond 2500 miles, orient antenna wire toward the
desired compass direction and install as high as possible.
Gain. The Windom displays unity gain relative to a half-wave dipole in
the same configuration on the 80 meter band. It exhibits increasing gain over a resonant
half wave radiator on higher bands as the major lobes become sharper and occur at
successively tighter angles relative to the wire . Power Rating is 500 Watts PEP in
amateur bands. If higher power levels are desired, order the 2KW version.
What's better than a Dipole? Everywhere? Answer? A multi-bander. Why? On
the lowest band it radiates just like a dipole, but it has more than twice the bandwidth.
How come? Because at the point where it's fed, the impedance changes proportionally less
with frequency. You notice it most on the lowest band, but you'll find broad bandwidth on
every other band too.
There's more-On the second frequency of resonance it has a lower radiation angle than a
dipole at the same height. This means wider coverage and more DX.
From there on radiation angle continues to drop and its gain increases relative to a
dipole for each higher band.
Our Windom is one easy to use antenna with lots of
performance, and its complete with a 98 foot feedline.