Hi Wes,
I have also always had the highest regard for 99.9% of anything that W8JI
has stated.
However, I feel exactly the same way about K2AV (and, of course, Rudy too).
In this particular case, I am inclined to listen to Guy and the others here
who have discussed and used the FCP.
Probably, the FCP is a little inferior to either lots of radials or a few
(two or more) elevated radials (like I have, which I assume is what is
meant by "gull wings"). But for those who do not have the room for the said
radials, K2AV's FCP is ab-so-lute-ly the way to go, isn't it?
Not to pick on Tom, but he posted his page about silicone dielectric grease
as a rebuttal to what I said about it, based on my particular experience
with the brand of grease I used at the time. That and his article about the
FCP are the only two times that I disagreed with him. :-) I was very lucky
indeed to have him as one of my elmers.
73, Mike
www.w0btu.com
On Thu, Jul 25, 2019 at 2:01 PM Wes <wes_n7ws@triconet.org> wrote:
> Personally, I would and do, avoid a FCP antenna. W8JI has done some
> analysis on
> these and I value his insight.
> http://www.w8ji.com/fcp_folded_counterpoise_system.htm There is simply
> too much
> handwaving going on to suit me.
>
> As to gull wing radials, Rudy Severns has looked at these too:
> https://www.antennasbyn6lf.com/files/antenna_ground_system_experiment_5.pdf
> Rudy's work is a treasure trove and I think I have everything he's written
> in a
> folder on my hard drive. Believe me, considering how difficult it is to
> lay
> radials in my cactus patch, if I thought gull wings would be useful I
> would have
> used them. I don't.
>
> Based on these and other resources, personal modeling and experiment and
> physical constraints, I opted for a ground-mounted 55' vertical,
> Inverted-L fed
> against 18 (so far) 55' insulated, on-the-ground radials. By serendipity
> the
> radials are resonant at about 1.85 MHz although that was not a design
> goal.
> Instead, I chose radial length be the same as the vertical height and I
> could
> get nine, 55' radials out of a 500' spool of wire with negligible waste.
>
> Wes N7WS
>
> On 7/25/2019 10:04 AM, Mark K3MSB wrote:
> > This kind of goes with the other thread that has morphed into the FCP
> > topic, but is a bit different.
> >
> > With an FCP feeding the INV-L, the bottom of the INV-L will be at least
> 10
> > feet off the ground. With my existing trees I can barely get up 50
> feet
> > from the ground. So, the INV-L will have 40 feet of vertical radiator.
> >
> > Using a pair of resonant gull winged radials feeding the INV-L at the
> > base, the vertical part will be 50 feet.
> >
> > From what I’ve read, the FCP is a better solution over a pair of
> resonant
> > gull wing radials, but I’ve also read that vertical length of an INV-L
> is
> > important. So there’s a tradeoff to be considered.
> >
> > Comments?
> >
> > Due to real estate considerations, I can put up only 2 one-half
> wavelength
> > resonant radials
> >
> > Mark K3MSB
>
>
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