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The Windom is a 1/2-wave horizontal dipole fed off-center by a single-wire non-resonant transmission line. It is named after L.G.Windom, W8GZ who described it in September 1929 QST. Although it is commonly called a Windom it is more properly described as Off-Center-Feed dipole.
A feed line is attached to an optimum point along the dipole by a BALUN. Taking one vertical angle and frequency with another, the RadioWavz DX (OCF) Windom is Omni directional.
Installation The best location for this antenna is as high and far away as possible from utility wires, other antennas, and other structures. It is impossible to find a perfect location, so the best compromise usually must be accepted.
The antenna can be installed in three basic ways:
WARNING: Always mount antennas so that they are out of the reach of adults and children. Contact with any part of this antenna can cause RF burns or other injuries. Constructing or erecting antennas where they may contact Electrical power lines can result in injury or death. RadioWavz is not responsible for any loss or damage resulting from the use or misuse of this antenna.
Horizontal Antenna: Requires two tall supports separated by more than length of the antenna. Suspend the antenna with at least a 50 pound working load nylon rope or another equivalent strength weather resistant non-metallic rope. Never use wire or wire core rope to support the ends of any antenna. Attach the rope to the end insulators through the empty holes. Try to keep the antenna as horizontal (level) as possible. The antenna should be at least 35 feet above ground to give acceptable performance on 40 Meters, and as high as possible for the best overall performance. The coaxial cable should drop vertically from the horizontal section of the antenna as far as is practical. If you are using trees for end supports, be sure to allow enough slack or some type of pulley and counterweight system to prevent the antenna rope from breaking when the trees sway in the wind. Try to keep the ends of the antenna at least five feet from metallic supports.
Inverted "V" Antenna: This method requires only one tall support and also places the least mechanical strain on the antenna. Hang the center insulator of the antenna from the support using nylon or other nonconductive rope tied to the center hole of the center insulator. The center insulator will be the highest point of the antenna. If possible, position the two ends of the antenna so the inside angle they form is at least 120 degrees. Secure the antenna ends with nylon or weather resistant non-metallic rope to suitable supports.
Sloped Antenna:
This antenna also can be suspended as a sloping dipole. This requires one tall support and one short support. The center (feed point) of the antenna should be at least 30 feet above the ground in this configuration. A sloping dipole radiates mainly in the direction of the downward slope. The optimum angle of "slope" will vary with the desired coverage and the frequency of operation, but will almost always be somewhere between 45 degrees and almost vertical.
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