Need some advice on EWE antenna (as described in QST a couple of times in last
18 months):
I have installed two EWE's in preparation for the fantastic 160 meter season
coming this winter. One points at 45 degrees toward Europe, the other at 250
degrees (from Indiana) toward the Pacific. Each has ten foot vertical sections,
one has a 50 foot horizontal and the other a 48 foot horizontal. Both are
terminiated by 1200 ohm resistors.
The first was run horizontal, with center clearance about 8 feet off the
ground, but as the lot slopes radically in that direction, the far end is
about 16 feet off the ground, and I need a six foot wire to the ground rod.
Ground rods are copper plated steel or copper tubing and are driven about 4 to
6 feet into the ground.
The second runs across the hill in a reasonably flat area, so both ends are ten
feet above ground and the center is 8 feet.
Ground conductivity is POOR, measured at 5 millisiemens/meter. Lot is heavily
wooded but the Pacific Ewe is in the clear.
Preamp is about 20 dB, located AT the base of the antenna, right after the
matching toroid. Very good signal strengths with preamp on, but with it off
still fair copy.
Now, here's the problem... neither antenna seems to be directional... both
receive equally well in all directions. With or without the preamp. My
next step is to replace the fixed resistors with variable and so some on the
air tuning... but before I put on my track shoes and do some flashlight
"tweaking" (not enough 160 meter signals here in daytime), has anybody else had
experience in optimizing directivity of a EWE in a hillside woods with poor
ground conductivity?
Also, with the preamp the noise levels and S/N ratio are same as any of other
antennas (half wave dipole, 80 meter vertical). I think that I need to LOWER
the antenna to drop noise levels relative to signal levels. But I don't want to
strangle a prowler or snare a deer. Any suggestions here?
Any body got experience with hills? Should the horizontal section be truly
horizontal or should it follow the hill? Optimally I would install a massive
horizontal ground screen under the antenna, with one end about 6 feet above
ground....... but the XYL draws the line there... so what happens if the
antenna points uphill or downhill ?
Thanks for reading
Mel KJ9C
I'd love to put up a beverage, but space is limited to about 290 feet and
there are WAY too many trees to detour around.
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