W4EF wrote:
>This has me wondering if these European signals
were coming in at very low-angles.
They are definitely low-angle on the East
Coast. I've gotten into the habit of using a
Beverage (peak 24 degrees TOA) with my transmit
antenna in diversity mode on receive. TX antennas
are either a 3-el vertical array (peak 22 degrees
TOA) or an inv-V up 30m (peak 90 degrees TOA).
"Break-even" TOA for these TX antennas is around 40
degrees. See comparative elevation plots here:
http://users.vnet.net/btippett/new_page_10.htm (top plot)
Recent European signals have been much better with
the vertical/Beverage versus the inverted-V.
It has been especially interesting to see how
far into daylight (both before sunset and after
sunrise) signals are being reported from all areas
of the world. I'm wondering if this is a combination
of the extremely low geomagnetic activity recently in
combination with extremely low TOA's. Could we be
grazing the ionosphere at such an angle that signals
are not being absorbed as much as usual? I'm not sure
why but I don't ever recall being able to actually
work Europe from my 35N latitude at 70 minutes
before sunset at this time of year. Of course
at more northerly latitudes, the sun is even lower
so there are reports of signals in even greater
amounts of daylight.
It's been a weird experience in the evenings to
tune across the band using a Beverage toward Europe.
European signals sound like locals (S9+) and Western
NA signals sound like DX. I believe this is due to
the very low-angle propagation since Beverages work
best (max F/R) at very low angles. See the very
bottom of the web page above for an elevation plot
of an end-fire Beverage array.
Whatever is going on, let's all hope we have
a few more years of this propagation ahead of us!
73, Bill W4ZV
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