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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