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Old October 20th 08, 04:39 PM posted to rec.radio.amateur.antenna
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
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Default Antenna design question

On Mon, 20 Oct 2008 08:40:35 -0400, Michael Coslo
wrote:

While looking for a way to get a little more bandwidth out of an 80
meter antenna, I mocked up an antenna in EZNEC that was thick. I plan on
making an antenna with spreaders and run 4 wires on each leg of the dipole.

I emulated this in EZNEC by simply making the wire thickness quite
thick, ranging from 4 inches to a foot.

The interesting thing was that as the thickness increased, the antenna
length decreased for min VSWR.

Is this a real thing?


Yep. It's called a "cage dipole". See:
http://www.smeter.net/antennas/wire-cage-dipole.php
with a program to help with the numbers:
http://www.smeter.net/software/dipcage2.exe

Even the ARRL uses them:
http://www.arrl.org/news/stories/2001/05/03/2/

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Jeff Liebermann
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