Rick, N6PE wrote: > The other question is does the thing actually work in the
real world?
I installed an inverted L over an FCP for 160M and compared it to 3 other
inverted L's over two elevated radials using RBN, real signal reports, and DX
pileup busting. In addition, I attempted to compare it with field strength
measurements with a friend using a spectrum analyzer on a hilltop 5 miles from
my hilltop. All antennas were up simultaneously. During the field strength
tests, I floated the radiators of the unused antennas. In addition to my own
antennas, I helped K8RRT commission an inverted L over FCP. The FCP replaced a
single 1/4 wave elevated radial, with which Tim worked 160 DXCC in two or three
years. At my place, an attempt was made to quantify the difference in
performance between my FCP and a pair of inline elevated radials. These are
both compromise radial systems compared to the ideal or near ideal. My attempt
to quantify the performance difference was unsuccessful for two reasons.
First, I have towers and other antennas which are in close pro
ximity to the L's, close enough that I suspect coupling is impacting the
performance. Second, due to my rugged terrain and steeply sloping ground, I
think the antenna position on my hilltop relative to the ground slope is as
important as any other factor in determining how an antenna works in a given
direction. I believe at my location the FCP is roughly equivalent to two
full size 1/4 wave elevated inline radials, based on the RBN reports and other
tests. DX performance in pileups for the FCP seemed similar to 2 elevated
radials, given where the antenna was mounted on the hill. I had no trouble
breaking any pileup, including KH2, RI1ANF, VK6 and many EU stations., using
the FCP antenna. This is anecdotal evidence and does not prove anything
scientifically, but I was unable given the circumstances to quantify the
performance difference. With the recent wind and snow storm, I have run out of
time to do further testing. My 1/4 wave elevated radial tree supported inv
erted L's have been very satisfactory for my use, and have resulted in Q's
with 7O6T, TT8TT, NH8S this year and South Sudan last year. I would like to
compare these minimal elevated radials with antennas equipped with optimized
radials, but this is not in the cards at my rock cliff location. Bottom line,
from my perspective, the FCP seems a viable alternative to two inline elevated
radials if one does not have space for the full size radials. Regarding
K8RRT, Tim is having success this season in the relatively poor condx,
especially since his time is limited due to a heavy work schedule. He has
busted many pileups with his tree mounted L over an FCP, including RI1ANF, NH8S
etc. A couple of days ago, Tim worked ZS1REC, one of only two NA stations to
make it on that night to Raoul. In terms of DX pileup success, Tim's FCP is
working. I realize this does not quantify or prove anything, but it is
additional evidence the FCP does work. How and why it works, I will de
fer to K2AV for explanation.
It could be the FCP and two inline elevated radials are many db down from the
ideal or near ideal ground system, I have no way to determine that with
testing. Given the simplicity of my setup, I am more than satisfied with the
DX results achieved with the elevated radials and believe the FCP would
generate similar results. My location may have something to do with the
results but if so it is not due to good ground conductivity, because my
antennas are over thick sandstone. It certainly seems the FCP is worth
trying if one wants to work DX from a limited space location. During the pre
Stew, I did a lot of listening but attempted no Q's. Consistently, K2AV had
the strongest signal here in WV of any station I was hearing, including many
big guns. Not sure how much power Guy was running, but he was consistently
over S9, at times up to 20 over, well above other stations in S meter reading.
This does not prove anything, but I offer the observation as another
indication
the FCP is worth considering for limited space. I know the value of
measurements and controlled tests but have no more time to spend on this
project. Thus, it is back to working DX with the status quo antennas. I will
leave it to the experts with more time, skill, equipment, and space than I have
to prove or disprove in scientific terms the merits of various ground/radial
systems. 73 Charlie N8RR
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