For those of you who missed the first couple of chapters, I tried a new
antenna a few months ago - a 105 foot tower with a full sized 3 element
40 at the top of it (and a few other monobanders down the tower). I used
the reverse feed method described in "the book" - which was "created" by
N4KG.
My feedpoint was about 40 feet up the tower and I used a drop wire with a
cap to hopefully reduce the current flow down the tower from the feedpoint.
I had four "radials" running out nicely - all 1/4 wave and with an average
height of about 15 or 20 feet.
Until the ARRL 160 contest, I didn't have much of a chance to feel how well
the antenna was working. The first night of the contest suggested that the
antenna was perhaps average at best. When KL7RA compared my signals to others
and answered "poor", that was the final straw.
As Dr. DX has point out, there is more magic involved with 160 meter antennas
than any other band. The magic just wasn't working for me with this antenna.
We had blue skies on Saturday, so I spent most of the day outside resurecting
my old antenna. This is a 72 foot tower with a 4 element 20 at 73 feet and
a 5 element 15 at 80 feet. I had removed the radials for this hoping to do
something better with the new tower (which is still a possibilty someday in
the furthur).
So - I put down about a half mile of radials down on the ground and put the
gamma match back up. After a couple of attempts, I had an adequate match
and used the new antenna for the second night of the contest.
It felt like most of the old magic was back. When I heard people, I called,
and they came back. I was even able to have guys on the east coast answer
my CQs (there was a nice peak during the 05/06Z hours). Most stations were
louder on the vertical, although the W6s were better on the dipole still,
as were the JAs in the morning (the dipole has always been the better antenna
in the morning to the Pacific and Asia - it is up about 90 feet on the top of
a 150 foot dropoff to the west).
It sure seems like the other antenna should have worked as well, or better...
but perhaps I didn't find that "magic" point on the tower to load it at.
Perhaps the tower needs to be taller so that my feedpoint can be raised
up higher - closer to a quarter wavelength above the ground. I might also
need to put some radials at the base of the tower to make sure it is at
a low impedance. It could also be that my homebrew balun was the problem
and I need to improve that. Maybe next summer, I will make another attempt.
At any rate - the N6TR/K7RAT signal is back!! See you in the Stew. I'll string
my beverage up through the horse pasture for the second night.
Tree N6TR
tree@kkn.net
PS: Just received my XR0X QSL card - first new one in a LONG time (I think
it was 4W/N6FF before that).
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