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Old November 12th 07, 04:27 PM posted to
Jim Lux Jim Lux is offline
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First recorded activity by RadioBanter: Mar 2007
Posts: 801
Default a little 4nec2 help?

Jerry Martes wrote:
wrote in message

On Nov 10, 11:16 pm, "Jerry Martes" wrote:

wrote in message


until now I have used 4nec2 to model cubical quad type antennas. Now,

I can make a helix with EZNEC very easily. I located the ground end of
the helix slightly away from ground. A short wire from the ground end of
the helix to ground becomes the feed.
Contact me at my E-mail and we can try your dimensions.
I'd sure like to learn to maneuver in 4nec2. This may be a motivator so
I can get more familiar with 4nec2

Exactly right. Either end the helix on the ground plane and put the
excitation on the first segment of the helix, or create a short segment
that connects the helix to the ground plane, and put the excitation there.

The trick in modeling a helix isn't the helical part, it's the ground
plane. Radial wires with circles, a rectangular grid of wires, etc.
For simple hacking, just point the helix straight up and use a perfectly
conductive ground.