> Here in Georgia, the path to Europe is further from the lossy polar
> regions, but the bulk of the path is along the poorly conductive and
> ray scattering Appalachian range. European signals are ALWAYS
> disappointing on 160, while a quick drive a few hundred miles east
> puts nearly the same path over salt water. 250 miles east signals are
> consistently much stronger, and this is always evident when I'm mobile
> on 160 making regular night time trips back from a race track about
> fifty miles inland from Savannah, Georgia.
Interesting.
> In southern California, over salt water paths, JA and VK signal
> levels are VERY strong. When I was working in California two years ago
> (a two month stint at an amplifier manufacturer with weekend trips
> home) I connected a receiver to small amplified loop. The JA's were
> well over S 9, and so were several VK's. The SAME type of antenna
> produced dismal S3 signals from VK and JA here in Atlanta.
I can offer the following observation - JAs are much louder up in
the pacific northwest than they were in southern California. The
VKs are about the same.
> There certainly are exceptional nights at every location, when
> ionospheric losses are low (when the MUF and OWF are low). But
> even during propagation "hot times" east coast salt-water-path-boys
> have several dB advantage over us poor saps who have to launch
> multi-hop propagation that depends on poor soil for half the bounces.
I guess the proof of ducting would be if someone in the middle is
shut out. This seems to have happened several times with ZS and
maybe even ZS8, but I think this might have more to do with being
on the opposite end of the world than ducting.
> I suspect ducting is NOT part of normal 160 propagation, since
> ducting would completely eliminate the effects of lossy terrain
> along several hundred or thousand miles of the path. If ducting were
> common, the 250 mile east south east single night move I sometimes
> make would logically NOT consistently enhance Eu signals, and 500 mile
> southerly trips would just as logically NOT enhance VK's along with
> the Eu's.
Do you think ducting is responsible for the echos I have heard?
This would seem logical. It is interesting that most of the time
that I can hear the echo - the band isn't very productive. There
is only one time that the band was open to Europe and I had echos
at the same time.
There also was the time I was in Texas (near Austin) at the QTH of
WN4KKN/5. We put up an inverted vee at 90 feet for the CQ 160 test
(I am pretty sure it was 1989). We worked a ton of Europeans
(one right through AA1K) and everyone else thought the band was
dead. One European after the contest, told Trey that the band was
very selective. For awhile, the only signal he could hear was WN4KKN/5.
Later, the band shifted, and all he could hear was N6TR/5. The only
thing that shifted was the paddle.
Perhaps just is just one of those funny nights - or maybe it was
a high angle thing and our dipole played to it.
Finally, there are times that KH6CC can work Europeans that I can't
hear. When this first happened, I couldn't believe it, but it is
a different path and doesn't support the ducting thoery.
Tree N6TR / K7RAT
tree@contesting.com
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