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Old July 6th 06, 09:46 PM posted to rec.radio.amateur.antenna
[email protected] w8ji@akorn.net is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 46
Default Voltage feeding a VHF yagi

Bob Bob wrote:
I havent but Mr Cebik talks about it on his website;

http://www.cebik.com/vhf/jp4.html

Cheers Bob VK2YQA

wrote:

Anyone ever get around the VHF FM vertical yagi feedline routing
problem by voltage feeding the bottom of the driven element with a stub
like a J-pole? A quick EZNEC run seems to indicate that it's not a bad
idea.


The problem with many models is people just stick a source at the
feedpoint and assume it tells them something about how the antenna
works in the real world.

A model has a PERFECT source that is like using a perfect balun and a
transparent feedline. I can build a very feedline critical antenna with
horrible balance issues, one that will never work in the real world,
and make it behave quite well in the model.

I would never use a J-pole feed on a Yagi, except perhaps in a model.

73 Tom