"Wayne" napisal w wiadomosci
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"Szczepan Bialek" wrote in message
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Uzytkownik "Wayne" napisal w wiadomosci
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wrote in message
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On Friday, April 26, 2013 12:38:06 PM UTC-5, Irv Finkleman wrote:
snip

Maybe SB can explain the difference between a monopole with a single
ungrounded radial, and a dipole.

Each radial, grounded or not (but connected to the shield of the coax), is
the ground.
The Earth, the Moon, a satelite and each piece of conductor is ground for
antennas. Radial is one of them.
Ground must be adequate to kW.

What if the single ungrounded quarter wave radial is in line with the
quarter wave radiator?
Is it still a monopole?

Of course.

Monopole is not directional.

Does this assume the monopole is vertical?

In the space no the directions.
The monopole radiate from the end part of the wire. So the one mast is
enough.
But you can make the two masts.

What if it is horizontal? Is it still non-directional?

Of course.
To have the directional antenna you must have the antenna array:
"An antenna array is a group of radiators whose currents are of different
amplitudes and phases. They use electromagnetic wave interference phenomena
to enhance the radiative signal in the desired direction and diminish it in
the non-desired direction". From:
http://en.wikipedia.org/wiki/Antenna...lectromagnetic)

The electrically symmetrical dipole is the antenna array.
The whip antenna is always non-directional. But in mountains it work better
if it is horizontal.

Each antenna made of wire radiate from the end piece of the wire. So the
wertical radiate in the all direction but tangent to the Earht surface.
The horizontal radiate in direction of ionsphere. It is usefull in moutains.

The directional antenna has the lobes.
The monopole antenna shorter than 1/4 wave has no lobes.
But a long wire antenna have lobes. There are the many "poles" (nodes) and
the interference take place.
S*