The overall physics behind horizontal stacking of horizontally polarized
and antennas is pretty much the same as if we were talking about feeding
two vertical antennas (i.e, a phased vertical array). You get additions
and cancellations depending upon the distance between the two antennas,
the lengths of the phasing lines, and the direction involved. The nulls
and peaks are less likely to be predictable, though, and probably
wouldn't be as well defined (i.e., I don't think you'd get a sharp null
in some direction) since the horizontal elements don't look like a
"point" when viewed from above. I could imagine that the mutual
coupling between the two antennas is a strong function of the beamed
direction as well.
About the only direction where you can say with any certainty that you
have a beneficial effect is when you are beaming broadside to the
combination of the two antennas and are feeding them with transmission
lines of equal electrical length.
73,
Dave AB7E
On 3/14/2013 4:26 AM, Cqtestk4xs@aol.com wrote:
There's the rub...they may work. Unless you can analyze them and include
data for length of feedline, distance and terrain it's all guess work.
Make one feedline 1/2 wavelength and you'll have a great local ant but one
that pretty well sucks for DX. Plus, if they are more than a wavelength apart
the "stacking effect" starts to drop.
However, it never hurts to try.
Bill K4XS/KH7XS
by 1In a message dated 3/14/2013 10:34:25 A.M. Coordinated Universal Tim,
jpklemola@gmail.com writes:
No problem.
Just connect them and if they work as separate antennas, they pretty
often work stacked, too.
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