Hi Dan,
Your observations are probably the best thing going for understanding what
happens at sunrise.
I doubt any of the rest of can actually "see" what is going on, all we know
is what antenna "works" better.
My problem is not knowing why one antenna is better than another, and
having to guess. I dislike guessing.
> there. We did not measure radiation angle, we measured hop distance
which
> is a function of takeoff angle. In this context, low angle would be
> somthing like 1200 miles or more per hop, high angle would be less than
1200
> miles.
What distance was the first hop Dan? Did you measure frequencies as low as
160 M?
> My observations were done with huge vertical arrays, so that says nothing
> about the polarization question. Additionally, there are many other
factors
> which could affect antenna performance. Efficiency, far field ground
> conductivity, geography, geomagnetic location, noise, etc. Nonetheless,
I
> would think that at least some of high angle reports around dawn are, in
> fact, real.
I certainly agree. It is ONLY at sunrise I find the dipoles useful,
approaching or even beating a vertical.
The question is WHY are they better. Is it polarity or wave angle?
I suspect wave angle and probably not polarity, but it is only a guess. I
suspect the wave angle is around 20 degrees or higher at sunrise (and
mostly on exceptional codx days) , and MUCH lower earlier when the sun is
not illuminating the upper ionosphere.
73 Tom
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