Thanks, Bill, to you and all the others for such quick replies. I guess my
description wasn't very clear, though, because the 40 degree gradient I
described slopes downward toward the northeast, not upward. My lot is at
the edge of a mountainside that slopes sharply up to the west of me and more
gently downward to the east of me.
Your comment about the best bearing to Europe from Arizona is very
interesting, though. Yes, I can orient the beverage on a face of the
hillside that looks more eastward than northeastward. Even more interesting
is that the transmitting antenna I used this winter (a 2 element wire yagi I
suspended 175 feet high across the canyon a bit further back in the
mountainside) beams about 75 degrees bearing. I was thinking of trying to
reorient it to point further north but probably won't bother now. You just
saved me from playing mountain goat again.
Thanks again to all.
Dave AB7E
----- Original Message -----
From: "Bill Tippett" <btippett@alum.mit.edu>
To: <topband@contesting.com>
Sent: Saturday, May 15, 2004 4:37 AM
Subject: Topband: Hillside Beverage Antenna
>I'd like to know whether a beverage antenna running up a steep
slope would have better or worse performance compared to one on
flat ground. The slope in question is fairly consistent at about
40 degrees
Probably worse if you want low angles. I recall a
~1 wl Beverage has a takeoff of ~35 degrees over flat ground,
so yours may be more like 75 degrees. Remember that the
ground underneath the wire is also part of the Beverage antenna.
Conversely, if you run a Beverage sloping down in the desired
direction, it should lower your takeoff angle. If you have
a 40 degree slope toward Europe, you will also probably have
some blockage at low angles on your TX antenna. However, it's
always worth trying rather than speculating about theory. If
a vertical/Beverage combination doesn't work, an inverted-Vee
might work better for both TX and RX. Of course having all
of the above is best! ;-)
From Arizona you may find your best azimuth for Europe
may be around 70 degrees instead of direct at 40 degrees. I
found that was true from my QTH north of Denver over the 9 years
I operated on Topband from there. This is due to the signals
being skewed by the geomagnetic field which affects paths in that
direction (Magnetic North from Colorado was about 13 degrees and
I suspect it is similar for Arizona). Hopefully a Beverage at 70
degrees bearing might be at a gentler slope. I know K0RF has
good luck with Beverages running sideways on the side of the
plateau he is on.
73, Bill W4ZV
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