Topband: FCP versus loaded or "T" radialsradials

Richard (Rick) Karlquist richard at
Sun May 5 23:30:04 EDT 2019

On 5/5/2019 11:32 AM, Floyd Sense wrote:

> If the argument is that the FCP can't be accurately modeled, maybe 
> someone can explain just why that is.
> 73, Floyd - K8AC

You can't simply enter the geometry into modeling programs because
you have 4 or 5 wires in close proximity to each other.  There are
work-arounds for simpler schemes like folded dipoles, but they
are not amenable for the more complex geometry of the FCP.  My
opinion is that whatever can be done with the FCP could be done
just as well with the same set of multiple wires connected
as a simple multiconductor radial with a loading coil.  In some
sense, an FCP is like a linear loaded element, only it is a radial
not an element.  I don't know anyone these days who thinks
linear loading is superior to lumped loading for elements.

All of this should not be construed to mean that the FCP doesn't
work.  We just don't know exactly why it works, nor can we predict its
performance in advance based on first principles.

Rick N6RK

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