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Old August 30th 05, 01:34 PM
Cecil Moore
 
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dansawyeror wrote:
To this point I do not know where the radiation comes from. I suspect it
is from the antenna. The easiest case is to model a poorly balanced
dipole directly feed by coax. It radiates significant power back down
the shield.


Actually, a perfectly balanced dipole can also radiate from the coax
shield because coax is unbalanced. Take a look at www.w2du.com and
www.eznec.com for information on baluns and chokes which tend to
reduce feedline radiation.

It appears to me that you may be confusing "balance" with "matching".
Those words have very different definitions.

A balanced 50 ohm antenna fed with coax and having an SWR of 1:1 is
matched but unbalanced and is likely to radiate from the feedline.

A balanced 50 ohm antenna fed with 600 ohm balanced line and having
an SWR of 12:1 is unmatched but balanced and is not likely to radiate
much from the feedline.
--
73, Cecil http://www.qsl.net/w5dxp


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