Thank you for answers (and lessons on noise and porpagation).
It appears that "one way" propagation is also happening between East Coast
and West Coast. So it appears to be more "east-west" phenomenon rather than
specific "ocean" phenomenon. Maybe more pronounced at the ocean front, due to
salt water help. Yes, there is some effect of noise being louder at one end,
but I dont think to the extent we see it. As I mentioned in my "ducting
propagation" article, I believe there is quite a bit of ducting in the layers
happening, with different angles of entry and exit at both ends.
More observation, testing and information is needed to determine what are the
prevailing angles of arrival for signals at both ends of the duct. (If we
were strictly reflecting, it should be reciprocal. Isn't mirror working both
ways?) Not easy to do on 160, but at least comparisons of vertical vs.
horizontal and various heights could give some indication.
There is also skewed path early in the openings, where signals would be
pulled towards the equator. This I have seen from 40 down to 160 where Eu or
JA stations would start coming from East or West and swing with depth of the
opening to direct short path NE and NW resp.
When I was experimenting and testing my stacked Razors (that's 7 el.
Quad-Yagi on 62 ft boom on 15m) on 20, 15 and 10 m. I have found that there
was a disagreement between the best transmit and receive angle for good 80%
of the time. Meaning bottom antenna would be loudest on transmit, while top
or stack would dominate on receive, or vice versa. This would indicate that
there would be different optimum angle for receive vs. transmit most of the
time. (Yea, your propagation simulation software doesn't show that!)
Sooo, interpolating this to low bands, this could be even more pronounced and
as we see it at the early openings, it is there. Now question and problem
solution is to figure out is, what are the angles and how to "defeat" them.
If the angle at the western end (we hear 'em, before we can get 'em) needed
is high, then we need some gain antenna shooting up at high angle. (Dipole
not good enough obviously.) Maybe some tinkering with angle or reception cone
at the eastern end also needed to quiet down the ambient noise and QRM.
Anyone willing to work on this problem, please let me know. Experiments and
reception reports would help. I will try to have some more antennas in the CQ
WW CW and other 160 m contests this season.
Hey, ducting works for me, just improved my CQ WW SSB score on 160 by about
65% and still missed about 15 countries that I heard and never worked (they
kept calling CQ!).
CU in the next one!
Yuri Blanarovich
K3BU, VE3BMV, P40A, op CG1ZZ
one of TESLA Contest Sparks, N2EE, NT1E
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