Congrats to those out West that have VP8STI in the log. You guys
certainly had the good draw and the right angle. I did work them on 80m
using OMNI short vertical and 100W. They however were not even moving
the S meter.
I offer my theorem on why Western US contacts are infrequent in this
case. Using my station and beam heading to the SE I worked CE1/K7CA
using QRP. I could do that from early darkness until his sunrise.
considering I've worked all of south America with 100W the extra 1500
miles should not be difficult especially being a trans equatorial QSO.
The conditions would also have to be very disturbed with no direct polar
region influence.
Looking at the VP8STI website they provide topographic and satellite map
of their physical location which is located on Thule Island to provide
safe harbor. I note to NW is Mt Larsen about 2 miles away. It rises some
2500 ft and the terrain effectively disrupts everything below 15 degrees
or nearly half of their vertical beam-width. This antenna is not in salt
water and a good guess would be that it has about 30 1/4 wave plus
radials. They have a clean shot to Europe in the far field. The NW path
is broken by Thule Mountain and along the way is going to pass through
the Andes Mountains. I would suggest the ground reflection element in
this case is scattering, which also causes increased path loss. This is
much like attenuation cause by the Rocky Mountains to Europe from
western US. Of course this the height of the F layer is a factor as well.
Responding to an earlier post by K7TJR regarding K7ZV mountain location.
I will take a QTH with extensive wide open flat land or slightly sloping
down hill over a mountain top any day. The curvature of the earth and
far field reflection is important (slight far field gain). I am not
saying that a mountain top won't work for 160. Heck, it might be
possible to build an antenna that is flexible on take off angle.
73
Bob
--
W7RH DM35OS
Only two things are infinite, the universe and human stupidity, and I'm not
sure about the former.
Albert Einstein
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