Bob wrote:
...snip...
But I start a thought and ended up with the fact that their signal surely
was down respect to the others I heard.
So I thought one reason could be the distance of these stations from the
ocean, since the overall distance from my qth shouldn't be so significant,
and probably within a few percent.
...snip...
Bob,
Your observation has been a topic of discussion for as long as there has
been a Topband. Your table illustrates how even a few hundred miles over
land can attenuate signals to the noise floor.
I have a propagation aid that I use here all the time. It's a 9" globe that
has been re-fitted with a new axis of rotation that includes my Minnesota
QTH, which is just south of the Canadian border in the middle of the US.
While I do have Italy in my log, QSOs to your part of the world are
extremely rare, and usually follow an unusual propagation mode (path) that
can only be a point of speculation. The magic behind using the globe is
that the frame of the globe follows the most direct path from me to any
location on earth. You are at about 45 degrees to me, and I am about 315
degrees from you.
The direct path between us, starting at your end, follows the entire length
of Italy, all of France, England, Ireland, open Ocean to Newfoundland (just
barely missing Greenland/Iceland), all of Quebec, all of Ontario. The
"earth" path between us is almost 3,000 miles. The "earthed" path between
you and North Carolina's coast is only a small patch of France on your end
(abt 200 miles).
Many people on our side of the pond experience a skewed path between us.
Generally, stations here will often aim their directional antenna South East
(135 degrees) instead of North East. The reasons for the 'skew' is a point
of violent contention on this reflector. Some profess it to be simple
back-scatter of signals that follow the path of least resistance over ocean
paths. Others profess it to be some sort of E-F layer skip that meets with
mysterious layers of wave-guide-like sections of the ionosphere. Then there
is the grayline advocates (following the dawn/dusk line). There are a few
other theories out there as well--all of which are educated speculation
based on the physics of radio. Whatever the reason, you are experiencing
the magic of Topband. It has been proven that the entire planet is open to
you at some point or another.
It is not uncommon for the path between you and me, or the path between you
and Oregon (in the western US), to be open and you would be unable to work
the east coast stations that you currently hear routinely. These paths
occur from time-to-time and are only available to you when you are at the
radio listening. When they occur, they almost never continue beyond that
moment.
The bottom line is that improving your reception abilities would improve the
likelyhood of QSOs deeper into the NA and SA continents. Around my part of
the world, one of the best reception antennas is a beverage or a small loop,
although some of the most spectacular openings have only been workable with
a low dipole. You cannot have enough antennas for Topband.
Good luck... And welcome to the wild-and-whacky-world of Topband. Once the
bug bites, there is no known cure...
73
Ford-N0FP
ford@highmarks.com
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