Pete
I would be wary of substituting lumped inductors for linear loading. You
want to represent the harmonic resonances and changing the loading type
will very likely make a difference (can't say how much, though). If you
model the linear loading stubs, be sure to set up the segmentation to align
the
pulses on adjacent wires. NEC and MININEC aren't real happy with
extremely close spacing, but will tolerate the condition with pulses
aligned.
The designer should have made sure that the 3rd harmonic resonance falls
well outside any ham band by wise placement of the loading. Maybe F12
already knows the answer you're looking for.
73, Gary
K9AY
>
> I would like to model a Force 12 EF-240S. I wonder if it would be
> reasonable to do so using lumped inductive loads in the elements instead
of
> the linear loading, adjusting the elements by cut-and-try to the resonant
> frequencies specified by the factory for tuning the real antenna? I
> realize that any cancellation resulting from the loading wires being
folded
> back toward the center of the antenna won't be seen, but my hope is that
> the model will at least be useful for assessing likely interaction with
> other antennas nearby. What do you think?
>
> If this approach would work reasonably well, I wonder if anyone has the
> dimensions of the elements, since Force 12 omits them in their
> documentation on the antenna (which I already own).
>
> Thanks in advance.
>
> 73, Pete N4ZR
> No, no ... that's WEST Virginia
>
>
>
>
>
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