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Old April 27th 13, 07:29 PM posted to rec.radio.amateur.antenna
[email protected] jimp@specsol.spam.sux.com is offline
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First recorded activity by RadioBanter: Jun 2006
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Default Anyone know where I can find plans for an artificial ground?

Szczepan Bialek wrote:

"W5DXP" napisal w wiadomosci
...
On Friday, April 26, 2013 10:52:18 AM UTC-5, Szczepan Bialek wrote:
The dipole with grounded one leg is quite different from the "symmetrical
dipole".


According to the official IEEE definition of a "dipole", it is any antenna
with approximately the same radiation pattern as a dipole.


Of course: "Dipoles have a radiation pattern, shaped like a toroid
(doughnut) symmetrical about the axis of the dipole. The radiation is
maximum at right angles to the dipole, dropping off to zero on the antenna's
axis. The theoretical maximum gain of a Hertzian dipole is 10 log 1.5 or
1.76 dBi. The maximum theoretical gain of a ?/2-dipole is 10 log 1.64 or
2.15 dBi."


True.

The antenna like this:
http://en.wikipedia.org/wiki/File:Di..._in_meters.png

". However, coax is not symmetrical and thus not a balanced feeder. It is
unbalanced because the outer shield is connected to earth potential at the
other end. When a balanced antenna such as a dipole is fed with an
unbalanced feeder, common mode currents can cause the coax line to radiate
in addition to the antenna itself,[5] and the radiation pattern may be
asymmetrically distorted"


True to a point.

The outer shield may or may not be connected to earth potenial anywhere.

Such antenna is MECHANICALY symmetrical.
But electrically is rather like the Marconi monopole:
http://en.wikipedia.org/wiki/File:A6-3EN.jpg


Confused babble.

The antenna is the antenna and the feedline is the feedline.

Whether or not the feedline radiates is totally irrelevant to what the
antenna does.

This is something you are totally incapable of understanding.

Remember: The grounded leg is the radial.


Remeber: This is puerile, ignorant, nonsense.



--
Jim Pennino