All of the towertalk responses to this posting has been about rhombics, not
vee beams. I had a vee beam up for several years and took it down because
it wasn't all that helpful. My vee beam was 525' on each leg with the apex
up about 90' and the two far ends up about 30'. The apex angle was about 50
I did a lot of EZNEC modeling and determined that the gain of the vee beam
is highly dependent on the apex angle and of course the length of the wires.
The gain is in terms of wavelengths so that the 525' long vee beam was only
about 2 wavelengths on 80 (with a corresponding low gain) but was about 15
wavelengths long on 10 (with a possible corresponding high gain). The
maximum gain for a given leg length is highly dependent on the included apex
angle. What is perfect on one band is not good for the other bands. On 10
for example the gain was a very strong 20 dbi but the apex angle had to be
only about 5 or 10 degrees. (I forget the exact measurements).
The result was a very narrow lobe--not useful for most of the time. As the
handbooks have it, one can select leg lengths and apex angles to make the
vee beam usable on a number of bands but the gain is not any better than a
small yagi. With a Steppir Monstr, Steppir 2 element, and 80m dipoles up
the vee beam was not used and removed.
But if one can have about 60 legs each 525' long in a circle with switchable
connections at the inside to vary the
apex angle, then .......oh well!
----- Original Message -----
Sent: Wednesday, September 12, 2007 7:26 PM
Subject: [TowerTalk] HF Vee Beam Experience?
>I am looking for some real practical experience from those who may have
> used a commercial or home-brew vee beam for HF frequencies from 3.5 to
> 30 MHz.
> If you home-brewed yours, where did you obtain the terminating
> Henry - K4TMC
> Raleigh, NC
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