Gang,
I've done a lot of antenna experimenting over the years and tried many
things that should not theoretically work.
I've wrestled with trying to design a good 160M antenna system in my
covenant-restricted neighborhood for years. My current antenna is a 200'
stealth
dipole at about 30'. It has been a surprisingly good performer, despite the
fact that it runs along the side of my house and a neighbor's house, and the
houses are considerably higher than the antenna wire.
My new antenna isn't supposed to work, at least if you listen to the gurus.
First of all, it has no radials, per se. It uses an 8' by 8' ground screen
on the floor of the attic. As the attic floor is about 28' above the ground,
that makes it an elevated ground system, we've heard nay saying about that
too.
Second, the vertical section is too short, about 20'. I have a 20'
telescoping fiberglass mast that extends from the floor of the attic, up
through a
roof boot and sticks about 10' above the roof. So the ground system as well
as
half of the vertical section are indoors, in fact, the pole stands close to
the two tall water heaters for the house, and their associated vent stacks.
Third, the wire size is too small. I'm using #24 wire for the outdoor
portion of the antenna.
Fourth, as a variant of the inverted L, the horizontal leg isn't really
horizontal, it droops down below the level of the vertical section, to a tree
at
about 28'.
Fifth, the high voltage end of the wire is almost touching the ground,
certainly bad for losses.
Sixth, the antenna has amazing bandwidth, about 70kHZ at 1.5 to one or
less, something must be terribly wrong here.
Seventh, with such a compromised antenna, you probably need high power to
work anybody. I'm running about 80W from an Omni VI.
The antenna is a sort of weird-shaped inverted U -- about 20' up from the
attic floor, out 70' with a slight slope, with the final leg sloping down
about
35'.
To test the antenna, I got on last night for CQ160 for about a half hour,
and made 35 qsos, about 80% on the first call, to all corners of the US plus
VE3, VE7 and V31. Not bad from South Texas!
I'm not writing this as someone who is lacking in experience on 160m. I've
operated 160M from several very good stations, running both high and low
power. What's more, I'm not trying to diminish the wisdom of the antenna
gurus
out there, but I'm experienced enough to know when an antenna works. This
antenna works! I simply want to encourage anyone who thinks they need a huge
antenna system to be effective on 160M to think again, try stuff, and don't be
afraid to compromise a few laws. The results may surprise you!
Paul, K5AF
**************Biggest Grammy Award surprises of all time on AOL Music.
(http://music.aol.com/grammys/pictures/never-won-a-grammy?NCID=aolcmp003000000025
48)
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