"Ian" napisa³ w wiadomo¶ci
...
"Szczepan Bialek" wrote in message
...
Not me but Wiki:
"The monopole antenna was invented ...
For radioamateurs the one wire is enough. The dipole is useless for them.
They want to "transmit for longer distances".

S*

Hello old chap.

There is surely no point in posting quotations from Wiki if you do not
understand them.
The comment about dipoles being useless for amateurs is definitely
incorrect. The dipole is a very popular design of antenna for amateur
radio
use.

Do you mean the dipoles fed by the coax or by the ladder line?
S*

"Rob" napisa³ w wiadomo¶ci
...
Szczepan Bialek wrote:
The "ground plane antenna" is also the monopole:
"To function as a ground plane, the conducting surface must be at least a
quarter of the wavelength (?/4) of the radio waves in size. In lower
frequency antennas, such as the mast radiators used for broadcast
antennas,
the Earth itself (or a body of water such as a salt marsh or ocean) is
used
as a ground plane. For higher frequency antennas, in the VHF or UHF
range,
the ground plane can be smaller, and metal disks, screens or wires are
used
as ground planes".

Note that it does not say that it is sufficient to connect one side
of the antenna to the ground with a wire.

Note what Marconi did: "Marconi, who discovered if he attached one terminal
of his transmitter to a
wire suspended in the air and the other to the Earth, he could transmit for
longer distances."

A ground plane is something different than a wire to ground.

The nonactive leg of the popular "dipole" is connected with the braid of a
coax and the mass (chassis) of the transmitter.
The braid has many wires. Each of them is the radial.
S*

Szczepan Bialek wrote:

"Rob" napisa³ w wiadomo¶ci
...
Szczepan Bialek wrote:
The "ground plane antenna" is also the monopole:
"To function as a ground plane, the conducting surface must be at least a
quarter of the wavelength (?/4) of the radio waves in size. In lower
frequency antennas, such as the mast radiators used for broadcast
antennas,
the Earth itself (or a body of water such as a salt marsh or ocean) is
used
as a ground plane. For higher frequency antennas, in the VHF or UHF
range,
the ground plane can be smaller, and metal disks, screens or wires are
used
as ground planes".

Note that it does not say that it is sufficient to connect one side
of the antenna to the ground with a wire.

Note what Marconi did: "Marconi, who discovered if he attached one terminal
of his transmitter to a
wire suspended in the air and the other to the Earth, he could transmit for
longer distances."

Marconi was using low frequencies where the wavelength is so long that
his wires are comparatively short.

At frequencies where amateurs operate, the wavelength is comparable
to the length of the feedline and it no longer works like that.

A ground plane is something different than a wire to ground.

The nonactive leg of the popular "dipole" is connected with the braid of a
coax and the mass (chassis) of the transmitter.
The braid has many wires. Each of them is the radial.
S*

It does not work like that.
A quarter wave radial works because when one end is floating the other
end has a low impedance.

"Wayne" napisal w wiadomosci
...


"Szczepan Bialek" wrote in message
.. .


"Wayne" napisal w wiadomosci
...


"Szczepan Bialek" wrote in message
...


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.

Wow...you gave a lot to digest.

Just to understand the discussion, let's address the monopole with one
radial.

Assuming the monopole is 1/4 wave long, and has a 1/4 wave long radial.
The radial is in line with the monopole. Everything is ungrounded.

# The radial connected with the shield of the coax is the ground.


How does that configuration of a monopole with one radial differ from a
dipole?

The true horizontal dipole (electrically symmetric) radiate in one direction
only. A monopole in all directions.

So a half wave wire broken at the center is a monopole with a single
radial if it is fed directly with coax?

Yes. The one leg is the radiator and the second is a ground (like a
satellite chassis).

And it is a dipole if it has a balanced feed?

The true dipole is electrically symmetric. The same voltages but in the
opposite phase.
Thank this the interference take place and a dipole has the main lobe and
many side lobes.
With the monopole no lobes.

What if the coax feedline has a quarter wave sleeve, open at the antenna
but connected to the coax at the other end?
Is it a monopole or a dipole?

"Marconi, who discovered if he attached one terminal of his transmitter to a
wire suspended in the air and the other to the Earth, he could transmit for
longer distances".

As you know are many version of ground because the soil is not the best.
The sleeve, the braid of the coax and so on are only the better ground.

Dipole must be electrically symmetric.
If one leg is connected to the any version of ground such "dipole" radiate
as monopole.
S*

"tom" napisal w wiadomosci
. ..
On 4/29/2013 10:20 PM, tom wrote:
On 4/29/2013 3:50 AM, Szczepan Bialek wrote:
"Wayne" napisal w wiadomosci
Assuming the monopole is 1/4 wave long, and has a 1/4 wave long radial.
The radial is in line with the monopole. Everything is ungrounded.

The radial connected with the shield of the coax is the ground.

So what would happen if I connected my transmitter, which has a 50 ohm
{ostensibly) output with the hot lead of the coax connected to the
"radial" instead of the "monopole" and similarly with the braid?

Think long about this.


Just to clearly understand where you are on how this really works.

I am not sure if I understand you.

If you have the mechanically symmetric dipole than one leg with the coax
braid works as the radiator and the second as the ground.
If you change the terminals than your radial will be the radiator.

Do not you have any possibility to check which leg is active?
S*

On Tuesday, April 30, 2013 3:17:13 AM UTC-5, Szczepan Bialek wrote:

I am not sure if I understand you.

Gee... you think?

Szczepan Bialek wrote:

"Rob" napisa? w wiadomo?ci
...
Szczepan Bialek wrote:
The "ground plane antenna" is also the monopole:
"To function as a ground plane, the conducting surface must be at least a
quarter of the wavelength (?/4) of the radio waves in size. In lower
frequency antennas, such as the mast radiators used for broadcast
antennas,
the Earth itself (or a body of water such as a salt marsh or ocean) is
used
as a ground plane. For higher frequency antennas, in the VHF or UHF
range,
the ground plane can be smaller, and metal disks, screens or wires are
used
as ground planes".

Note that it does not say that it is sufficient to connect one side
of the antenna to the ground with a wire.

Note what Marconi did: "Marconi, who discovered if he attached one terminal
of his transmitter to a
wire suspended in the air and the other to the Earth, he could transmit for
longer distances."

Irrelevant to anything said, but you are too ignorant to understand why.


A ground plane is something different than a wire to ground.

The nonactive leg of the popular "dipole" is connected with the braid of a
coax and the mass (chassis) of the transmitter.

Pure babble.

Both legs of a dipole are "active".

Not all dipoles are feed with coax.

Some transmitters have no chassis or metal mass of any kind, a good
example of which would be radiosondes before transistors were invented.

They were build on a non-conductive sheet using point to point wiring
and had no metal mass, no chassis, no ground, and were hung from
balloons.

The braid has many wires. Each of them is the radial.

Pure babbling, nonsense.



--
Jim Pennino

Szczepan Bialek wrote:

"Ian" napisa? w wiadomo?ci
...
"Szczepan Bialek" wrote in message
...
Not me but Wiki:
"The monopole antenna was invented ...
For radioamateurs the one wire is enough. The dipole is useless for them.
They want to "transmit for longer distances".

S*

Hello old chap.

There is surely no point in posting quotations from Wiki if you do not
understand them.
The comment about dipoles being useless for amateurs is definitely
incorrect. The dipole is a very popular design of antenna for amateur
radio
use.

Do you mean the dipoles fed by the coax or by the ladder line?

It doesn't matter but you are too stupid to understand why.

And both methods of feed are very popular.

Repeat the following until it sinks into your only two functioning brain
cells:

An antenna is an antenna and a feedline is a feedline.


--
Jim Pennino

Szczepan Bialek wrote:

"Wayne" napisal w wiadomosci
...


snip

How does that configuration of a monopole with one radial differ from a
dipole?

The true horizontal dipole (electrically symmetric) radiate in one direction
only. A monopole in all directions.

A dipole radiates in two directions, idiot.

So a half wave wire broken at the center is a monopole with a single
radial if it is fed directly with coax?

Yes. The one leg is the radiator and the second is a ground (like a
satellite chassis).

Absurd nonsense.

And it is a dipole if it has a balanced feed?

The true dipole is electrically symmetric. The same voltages but in the
opposite phase.
Thank this the interference take place and a dipole has the main lobe and
many side lobes.
With the monopole no lobes.

Babbling gibberish as usual.

What if the coax feedline has a quarter wave sleeve, open at the antenna
but connected to the coax at the other end?
Is it a monopole or a dipole?

"Marconi, who discovered if he attached one terminal of his transmitter to a
wire suspended in the air and the other to the Earth, he could transmit for
longer distances".

This has nothing to do with the question asked.

You haven't the slightest clue what a quarter wave sleeve is or what it
does.


As you know are many version of ground because the soil is not the best.
The sleeve, the braid of the coax and so on are only the better ground.

Utter nonsense.

Dipole must be electrically symmetric.
If one leg is connected to the any version of ground such "dipole" radiate
as monopole.

More babble.

You truely are an idiot.


--
Jim Pennino

Szczepan Bialek wrote:

"tom" napisal w wiadomosci
. ..
On 4/29/2013 10:20 PM, tom wrote:
On 4/29/2013 3:50 AM, Szczepan Bialek wrote:
"Wayne" napisal w wiadomosci
Assuming the monopole is 1/4 wave long, and has a 1/4 wave long radial.
The radial is in line with the monopole. Everything is ungrounded.

The radial connected with the shield of the coax is the ground.

So what would happen if I connected my transmitter, which has a 50 ohm
{ostensibly) output with the hot lead of the coax connected to the
"radial" instead of the "monopole" and similarly with the braid?

Think long about this.


Just to clearly understand where you are on how this really works.

I am not sure if I understand you.

You don't understand anything.


If you have the mechanically symmetric dipole than one leg with the coax
braid works as the radiator and the second as the ground.
If you change the terminals than your radial will be the radiator.

Babbling nonsense.

Do not you have any possibility to check which leg is active?

More nonsense.



--
Jim Pennino