Mike/All
It will be very interesting to see what happens in Autumn when all the
leaves fall off. Given this is Alaska this could happen in a month or so and
I may still be here. This site has been dissapointing from 160/80m DX
perspective - the verticals/shunt fed towers have proved poor compared to my
previous Sites, and Im pretty sure its due to the density of the forest. The
trees goto around 90 feet and the forest in a few hundred acres deep,the
soil - glacial moraine, clays and sand, and I know the fresh water table is
around 100 ft down all have a hand in it. My experiences in conducting HF/LF
comms in the jungles of the world too compounds these "feelings" However Im
not disheartened at all - all Ive got to do now is decouple the tower to
eliminate losses there and see what difference that can make - this may be a
largest loss influence, and I might move the vertical section to midpoint
of the 3 wire large cap top.
I did add another load of close in 100 metre radials and electrodes but
again this has zero improvement too - Given the large number all ready in
place - the large earth mat for 160 under the tower, the well casing, it
looks like I reached the "PLR" - the point of limited return.. Shares in
Copper and FETS went up today on the stock exchange.
I might have a go at one of them TX loops after all! Nothing still from
DCF39 during nighttime, but at least it gets dark now at night. As before I
only see DCF39 during Hard Xray/similar events during daylight hours.
Laurence KL1X.
This test tends to confirm that what we call "earth losses" are often not
actually due to the resistance of the earth connection, but to absorption
by
vegetation, buildings and even hills. I once ran out a long radial - though
only 300m - and that did not improve my 100-ohm loss. It appears that the
site is of great importance, and there is a practical limit to the antenna
'gain' at any location. Factors such as height and ground covered by the
capacity hat are still worth improving if possible, though in many urban
areas these are limited by space and neighbours.
Mike, G3XDV
http://www.lf.thersgb.net
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