Perhaps it's just an "old wive's tale" but I think I once was taught (EM
Wave Theory 401) that the F-layer, combined with earth reflections, tended
to turn all signals into near horizaontal polarization. Therefore, with a
good vertical antenna you might start out with a nice low angle vertically
polaized signal that would be best be received, after one or two hops, on a
vertically polarized antenna, but more hops than that and a horizontally
polarized antenna would probasbly be preferred. Remember
however, with a lower radiation angle (and perhaps fewer hops) you may make
up the difference (e.g. a good 4 square vs. a yagii at 120 feet on 80
meters). And, no, I have never tried to porve this experimentally. Bottom
line, you probably will have to try to compute the path, perhaps with the
aid of HFTA, allowing for reflection losses and remembering that salt water
is a lot better reflector than granite.
Gene / W2LU
----- Original Message -----
From: <W0WOI@aol.com>
To: <towertalk@contesting.com>
Sent: Monday, November 08, 2010 2:45 PM
Subject: [TowerTalk] Polarization: Quad vs Horizontal at 50 mHz
> If Station A is using a traditional horizontal Yagi in contact with
> Station
> B using a horizontal Yagi, via 50 mHz Sporadic Es or some form of F-layer
> propagation, either single or multiple hop, does the signal remain a
> constant horizontal polarization over the entire path, or is the
> polarization
> twisted to be received in various polarizations?
>
> And a second question, is there an advantage/disadvantage to using a
> cubical quad at Station A and a horizontal Yagi at Station B?
>
> I ask this in view of a debate transpiring elsewhere.
>
> Both theorists or first-hand experience acceptable.
>
> Thank you.
>
> 73, Bill @ W0WOI
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