>
> Regarding gain, the vertical pattern may be slightly different for low
> quads and low yagis over typical grounds. It does not take a great deal
> of difference in lobe shape to make a large difference in low-angle
> radiation strength.
In addition, since the quad is, from one perspective, a vertically stacked
array, its elevation angle of maximum radiation is equaivalent to a planar
antenna at a point about 60% or so up from the bottom element. At great
heights, this makes a difference of only a few tenths of a degree.
However, at heights of 1 wl or below, relative to a planar antenna mounted
at the same mast height, the quad will show a lower TO angle. Hence,
comparisons between planar and vertically stacked arrays are often not
fully specified so that the reader can take all of the relevant variables
into account in evaluating them. (Why say "planar and vertically stacked
arrays?" Because the so-called Yagi/Quad dispute is only one example of a
broader subject.)
-73-
LB, W4RNL
L. B. Cebik, W4RNL /\ /\ * / / / (Off)(423) 974-7215
1434 High Mesa Drive / \/ \/\ ----/\--- (Hm) (423) 938-6335
Knoxville, Tennessee /\ \ \ \ / / || / (FAX)(423) 974-3509
37938-4443 USA / \ \ \ \ || cebik@utk.edu
URL: http://funnelweb.utcc.utk.edu/~cebik/radio.html
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