>
> No, hams are not crazy. Stacking antennas at HF is really done
> not to get the 2 or so db of stacking gain it is to get
> a better take off angle pattern - it is this change in pattern
> that accounts for the 10 db changes in signals when switching
> between the stacked antennas.
If all someone needs is a better take-off angle, that is, lower, then a
stack is detrimental, since the antenna pair actually raise the TO angle
relative to the TO angle of the upper antenna alone. However, the gain
does not hurt a bit and gives the operator a variety of TO angles using
the top only, the bottom only, and the pair together. In variety, there
is success--but at the cost of erecting and maintaining the stack.
Although 2 dB is only 1/3 of an S-unit, in the margins or in the piles, it
can make the difference between being one of many or THE one heard.
-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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