Thread: New antenna
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Old October 13th 07, 06:26 PM posted to rec.radio.amateur.antenna
art art is offline
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First recorded activity by RadioBanter: Sep 2006
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Default New antenna

On 13 Oct, 06:28, "Richard Fry" wrote:
"Dave" wrote and ONE MORE TIME.... define 'equilibrium'. write the equations.
just what is in 'equilibrium' with what??


__________

snip commercial AM broadcast stations, and its very high system
radiation
efficiency has been proven thousands of times since the earliest days of
broadcasting. Of course that is at odds with the beliefs Art continues to
post here and elsewhere.

In a response to my emails Art seemed to understand, and even thanked me for
"sticking with it." But I guess he was not convinced, because he started
this thread _after_ our email exchange.


RF
When a person E mails me in private he is suggesting an element of
trust
ie that it is private. When you betray that trust you can forget
about
any future discussion, private by E mail or public via the group
Art

Since my discussions with Art I put together a chart showing the groundwave
field generated at 1 km by several, fractional wavelength monopoles at
applied powers from 1-10 kW (see link below). I used a perfect ground plane
in preparing the chart, but the values would be only slightly less with a
2-ohm r-f ground.

ART: Note that the 1 kW field for the 1/4-wave monopole is exactly the peak
field of a 1/2-wave dipole in free space (about 313 mV/m). Taller
monopoles generate more groundwave field, given the same applied power and
r-f ground, because their radiation patterns have more gain in the
horizontal plane and less gain in other directions -- not because they are
more "efficient." All of the monopoles in this chart radiate all of the
power applied to them (100% efficient).

Also note, Art, that a 1/2-wave monopole and its ground image comprise a
full-wave antenna (eg, having your "equilibrium"), yet the 195-degree and
225-degree monopoles produce higher groundwave fields, even though they are
NOT by your definition "in equilibrium."

http://i62.photobucket.com/albums/h8...veFieldvsPower...

RF