[TowerTalk] Hygain 40M Beam Question

[K4FJ@aol.com]

Hi,

At our Barbados contest station we have the 3 element version of the Hy-Gain 
40M beam (Discoverer 7-3).  The elements use linear loading which is run 
close to the element.  The antenna is currently nonfunctional which is 
probably due to excessive corrosion of joints in the linear loading wires.  
We have experienced this several times before.  Rather than replace the 
linear loading again, I would appreciate comments on an idea that I have.  
Initially, I would propose this only for the driven element because we won't 
have time to completely overhaul the beam in the next few weeks.  I would 
remove the linear loading from the driven element, short across the insulator 
section (this is where the linear loading is inserted in the Hy-Gain design) 
in each driven element so that I have an element approximately 22 feet long.  
Then, I would attach wire near the tip of each driven element and pull the 
wire back to the mast but above the beam (probably five or six feet) so that 
the driven element resembles a triangle.  The ends would not be connected 
electrically---in fact they would probably be four or five feet apart.  No 
doubt the Hy-Gain Beta Match will have to go.  I suspect the overall length 
of each driven element (including wire length) will have to be longer than 
the resonant length determined by formula but I am willing to experiment with 
that part.

I would appreciate any comments.  Keep in mind this is intended initially to 
be a quick fix which would still allow the antenna to be rotated.

73, Steve

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