The feed impedance for a dipole varies similar to a damped
sinusoidal waveform as height is varied so whether it
increases or decreases depends on what part of the curve
you are traversing.
Tom N4KG
On Wed, 15 Aug 2001 alsopb <alsopb@gloryroad.net> writes:
>
> Marc,
>
> Just for kicks I ran EZNEC for a full sized 2 element beam (24'
> boom) at 24 and 28 M height.
>
> 24 M SWR =1.306 IMPEDANCE =38 -1.8j
> 28 M SWR =1.519 IMPEDANCE =33 -0.5j
>
> Interesting that the impedance actually decreases rather than
> increasing with height as the dipole impedance plot vs height
> predicts.
>
> I don't have a model for the 402CD. It would be interesting to
> actually run such a model at the two heights.
>
> Of course, these values are at the feedpoint. What the reading
> would
> be at the shack end of the coax is unknown.
>
> 73 de Brian/K3KO
>
>
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