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I designed this antenna to withstand the harsh wind, salt, and lightning conditions of the south. It's made of 6063-T6 aluminum and uses all stainless steel hardware. The coil insulators are made of delrin rod. The bottom coil is made of 5/16" solid rod and the top is 1/4" solid. The top of the antenna is terminated with a solid aluminum static dissipating tip which also holds the four static dissipating hat wires. These devices help the antenna dissipate static out of the air quieting the receiver and reducing the chance of a lightning strike. To further its ability to handle lightning, the bottom of the radiator element is connected directly to ground and RF is fed through a gamma match.
There are no little coils or parts to blow out. The weakest link is the connector itself, but if it gets flashed it's easy to replace. South Florida is the lightning strike capitol of the world and this antenna is made for it. (Wolf Antennas come with Lightning Warrantee) Four 9-foot ground radials are located at the base just below the connector bracket. They are attached to the center of the mounting sleeve with boom to element clamps and U-bolts.
A common flaw of the old style 5/8 wave ground planes
were they radiated most of the power low in the element close to the radials.
Then putting the matching coil at the very base of the element didn't
help the problem. In my new design top loading the element with inductance
(coil) and capacitance (hat) correct this weakness. The coil is about
5 feet below the top hat. This combination acts to pull more of the RF
current up the element increasing the antenna's efficiency.
Price $145.00 For
questions, comments, antenna orders, SPECS: Wolf Point 64_11m
The gain of a omni-directional antenna comes from bringing energy that's being wasted into the sky down to the ground. Two basic factors control this effect, the length of the antenna and it's height above the ground. The diagram below shows the side view of the lobe pattern coming from a 1/4 wave, (black line) 1/2 wave, (blue line) and .64 wave (red line) antenna at a height of one wavelength. The antenna is located at the bottom left corner of graph. The vertical axis points strait up and the horizontal axis is level to the ground. The difference is obvious, the pattern of the 1/4 wave is almost round and the pattern of the .64 is much flatter the difference in gain is almost 4 dB. This is called the "angle of radiation" or just "radiation angle" and is stated in degrees above the horizon. (NOTE: Secondary lobe of .64 ommited
for clarity) So then the gain is achieved by moving energy that went almost strait up and getting it down onto the ground where the receiving antennas are. The radiation angles are as follows: 1/4 wave = 32 deg., 1/2 wave = 24 deg., .64 wave = less than 15 deg. It can now be seen that the lower the angle of radiation the greater the distance will be. This is true for local and DX. |