Not many (only 2) responded to the posting asking for Vee beam info sources.
The best source I know of is the ARRL Antenna book (18th)
and that has only one page! But I find it to be very confusing when trying
to determine correlation of apex angle and wave angle (elevation?).
Also, I often hear hams referring to ~100' wires as long wires when used at
10m and 20m. While that may be technically accurate, I think that any vee
beam recommendation should include length of the wires as it makes a huge
difference for selecting the apex angle.
I have had a Vee beam up for about 5 years. It has an apex angle of 50
degrees (available trees at far end) and each leg is 520' long. The apex is
at 95' and the wires catenary down to about 20'. (BTW, I was never sure of
the apex angle which I tried to measure holding a protractor overhead while
trying to to get as close to the center of tree without the branches
obscuring the apex.. I am proud that it finally dawned on me to use a
digital camera, print the result and extend the wire lines on the print to
the hidden apex and then measure!)
I have used EZNEC to make many plots of Vee beam while varying the apex
angle, frequency, and leg length. I can't imagine trying to
design one without modeling capability. Since my Vee beam is 4L at 40m and
16L at 10m, I selected the trees which gave the 50 degree
apex angle as the best fit.
How well does it work? I really don't know. My Vee is aimed to the East
coast which should be excellent for the Sweepstakes contest.
However, the difference between a dipole at 70', a 320' dipole at 85' and
an A4S beam at 72' and the Vee was not obvious and I wound
up using the tribander most of the time during the recent Sweepstakes voice
contest.
hope this is of interest to some
k7puc
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