Mark Keith wrote:

Cecil Moore wrote:

Mark Keith wrote:
Bravo. Pretty much sums it all up in a nutshell. No one has shown an
example of gross modeling error to date.

What is the matter with the one I posted last week with phase-
reversing coils as described by Kraus on page 824 of _Antennas_
for-all_Applications_, third edition? If you missed it, look at

http://www.qsl.net/w5dxp/current.htm

What example? I look at the page, and all I see is a current
distribution model for an antenna using stubs. ?? Where is the model
of the one using lumped inductance?

Scroll on down. It's four 1/2WL array sections separated by a "phase
reversing coil".

I tried modeling a couple of
antennas myself using multiple 1/2 wave elements and inductance as
phasing coils just to test this out. But I used three elements instead
of four. I do not see any major change in current distribution when
compared to feeding all three with three separate sources.

Turn on the CI feature, display the current phase, and you will
see the difference. With EZNEC's lumped coils, the currents in the
outside sections are 180 degrees out of phase with what they need
to be.

But I do see a bit less gain with the lumped inductance version, and
not quite as tight a pattern. This *might* be a point of error, but
I'd have to look more carefully into that.

When you turn on the 'display current phase' feature, you will
see the difference. The currents in each 1/2WL sections are supposed
to be in phase. With EZNEC's lumped coils, they are out of phase no
matter what coil reactance is chosen. That's why there's more gain
using multiple sources. The errors are minimized using multiple sources.
--
73, Cecil, W5DXP