Re: NEC-LIST: Plotting circular and part-circular antenna elements

From: Jim Lux <james.p.lux_at_email.domain.hidden>
Date: Sat, 12 Jul 2008 19:04:18 -0400

Quoting Pete Smith <n4zr_at_contesting.com>, on Sat 12 Jul 2008 03:08:58 PM PDT:

> I occasionally need to plot at least a quarter-circle when modeling
> real-world antennas - an example is my K3LR lazy-vee array for 80m,
> where the bottom half of each dipole describes something approaching a
> quarter-circle on its way from the feedpoint to the bottom end (back at
> the tower). It would clearly be a better model to describe that lower
> element as a quarter-circle than as a straight line, for NEC's purposes.
>
> Does anyone have a table that describes a 2-dimensional circle in terms
> of X and Y coordinates? I'd prefer not to reinvent this particular
> wheel if it already exists somewhere.

there's a couple ways to do this without the coordinates.
Use GR card (which I've never used...)

Use GM card to make multiple copies of a sort segment rotated around
the axis of interest, then another GM to move it.

A zero height helix can also do it (although one of the online manuals
warns of a divide by zero)

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Received on Sat Jul 12 2008 - 23:04:18 EDT

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