Guy: great review of all that you did, as far as opting to go the "FCP route,"
and why.
I opted to go with sixty elevated radials and, like you, have some "proof" that
the decision worked for me as I just received my SO QRP #1 in the W7 section
certificate for the 2012 CQ WW 160 contest.
If I didn't have the option of positioning the base of my 43' vertical with 25'
top loading wires at the top of a sloping ground (the base of the vertical is,
in essence, 10' above the bottom of the wash below the sloped ground) and
running those elevated radials I would have gone the FCP route as all
indications are that "approach" is a winner.
After working NH8S on 80 meters, SSB and CW with QRP power I feel like my
antenna system is a good as it'll be for some time! I guess I feel like I'm "in
play," albeit I'll never "win out" over the likes of N7IR, WD5R and VE3MGY - Hi
Hi
72, my friend - Jim Rodenkirch K9JWV
> Date: Fri, 9 Nov 2012 19:59:10 -0500
> From: olinger@bellsouth.net
> To: weeksmgr@hotmail.com; topband@contesting.com
> Subject: Re: Topband: FCP
>
> Very kind, and flattering, but...
>
> I'm really NOT expecting to be the loudest guy. There is no reason
> for me to expect that. But I AM in play. My station, including the
> antenna wire + FCP, IS "working" and working well. I have a K3, with
> dual diversity RX, and an Alpha 8410. RX antennas are the limiting
> issue at my station. Working on that.
>
> I'm using an FCP at 7 feet with an 84 foot vertical wire plus 104'
> horizontal. It's strung in an open area in my narrow little private
> forest over the driveway almost to the US 64 service road. The
> driveway splits the property there, thus no possibility for radials.
> It's at 7 feet because I could do that and not have to clear some
> stuff, and it was an EXPERIMENT when we first put it up.
>
> I will be moving the FCP up to 15 feet, after clearing that stuff to
> make it possible, and raising the wire a bit at the same time, so it
> will be still be about the same wire above the FCP. I have 425 feet
> of WireMan #554 window line to the matching box plus about 80 feet of
> coax getting from the shack out to the tractor shed where the balanced
> line starts.
>
> I have a 4:1 isolation transformer to step down to the FCP-antenna
> feedpoint Z. It's a trifilar winding on a T400A-2 monster powdered
> iron core. Runs stone cold with 8410 in brick-on-key mode. Vacuum
> variable cap tunes out series inductive reactance in the nearly 3/8
> wave length wire. I use a duplicate of the isolation transformer to
> go to coax at the tractor shed. That way I have a working duplicate
> ready if the antenna end gets melted by a direct lightning. There have
> been four close strikes to trees, and the isolation transformer
> construction at both ends of the balanced line has stood up to induced
> voltage without problems
>
> My big maintenance headaches are parts of the forest falling on the
> feedline and squirrels eating the window line material and exposing
> the wire underneath to moisture. I have support weights on pullies at
> the ends of the main run, The window line can slip through the
> supports, which will also release with excessive pressure, and a tree
> can take the window line to the ground and pull up the weights without
> snapping or otherwise damaging the window line.
>
> There are a couple sweet gums growing into the antenna clear space
> that are going to be taken down shortly. This antenna is now known
> for sure to be the best 160m antenna I can get up on the property, so
> it will be maintained, and I can justify the clearing activities.
>
> As to FCP stories...
>
> CQ160 CW certificates are now out there for Jan 2012 contest. #1 SOLP
> in NC (#2 in 4th call area) was over an FCP. #1 SOHP in NC (#3 in 4th
> call area) was over an FCP.
>
> One Scot station with a new FCP in a 21 x 75 foot back yard (!!!), and
> a 30 foot tower for supporting the bend in the L, was on 160 in the
> CQWW SSB and worked into the US and all over Africa with 400 watts.
> Was night and day for him versus his prior setup with necessarily
> pathetic radials. What radials could anyone put down that work in 21
> x 75 feet? And that's *SSB* across the pond, which is at a 10 dB
> disadvantage to CW across the pond.
>
> Yeah, FCP really works, but it is certainly not a replacement or a fix
> for everything. Those without commercial radial fields, but who have
> stuff that works and compares favorably with others' RBN numbers may
> not get discernible performance boost by conversion. If you are
> getting cr*p RBN numbers on 160, then examination of your setup is in
> order, and you might get startling improvement with an FCP. Others
> already have.
>
> The FCP is best replacing "miscellaneous" attempts at radials that are
> a significant come down from commercial radials. These are usually
> because size restrictions prevent anything remotely resembling "full
> size dense and uniform all around". On the other hand, some are
> making no-performance-change FCP substitutions because they didn't
> lose anything and they got their back yard back. On fellow said he was
> tired of tangling his annual radials in the lawn mower.
>
> Some have put up their first real 160 antenna over an FCP because
> there was no way they were ever going to use radials, including some
> that clearly had room for the commercial equivalent. I hear a range
> of reasons (you've heard them all on this reflector) for not doing
> radials.
>
> 73, Guy.
>
>
>
>
>
> On Thu, Nov 8, 2012 at 3:00 PM, Guy Olinger K2AV <olinger@bellsouth.net>
> wrote:
> > On Sun, Nov 4, 2012 at 12:36 AM, Charlie Young <weeksmgr@hotmail.com> wrote:
> >> 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 proximity 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 inverted 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 defer 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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