A number of you have asked me what the local terrain is like and if it
makes my poor old low dipole work particularly well. I am about 6 feet
above sea level, about 50 miles from the North Sea, and there are no
hills in any direction for 18 miles. There are hills rising to 400ft or
so in most directions about 20-40 miles away and about 60 miles west of
here are the Pennines, rising to 1800ft.
The ground water table is about 4 feet below ground and the soil is a
rich loam about 2 feet thick over sand and alluvial clay. The dipole is
fed with coax and has no balun, the feedline is about 250 feet long. It
is supported at the ends and is normally about 45 feet above ground in
the centre, with 50-60 ft supports.
The only "special" feature is that there are eight heavy copper cables
and a 4 inch steel pipe duct running parallel to the dipole, buried in
the soil beneath it. They are spaced evenly from about 40 feet to the
west to 50 feet to the east, some are feeders, some are power cables, and
the rest are the ends of some 500ft radials from the base of a vertical.
The antenna itself is made from 12 gauge bare copper, and the pull on the
halyards is quite something. The bandwidth is very narrow, useable from
1825kHz to 1855kHz at under about 2.5:1 SWR.
I'd still prefer a nice halfwave vertical.
Neil G4DBN/AA1EG g4dbn@cix.compulink.co.uk
"I still need South Dakota as well...."
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