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Old August 2nd 07, 10:16 PM posted to rec.radio.amateur.antenna
Roy Lewallen Roy Lewallen is offline
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First recorded activity by RadioBanter: Jun 2006
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Default Grounding systems -- need the help of some good elmers

Bob Miller wrote:

The G5RV dipole is a balanced antenna and does not require a ground.
So unless you want one for some other reason, option 3...


The G5RV is a *symmetrical* antenna. Feedline radiation can still occur,
and often does. In that case, the antenna isn't *balanced*, in the sense
that the current on the two antenna halves isn't equal.

See Figs. 2-4 in http://eznec.com/Amateur/Articles/Baluns.pdf.

You need a truly balanced tuner in conjunction with the G5RV to assure
balance. A good current balun, instead of a balanced tuner, might be
adequate on bands where the input impedance is reasonable.

Roy Lewallen, W7EL