"Rob" napisa³ w wiadomo¶ci
...
Szczepan Bialek wrote:

"Rob" napisa3 w wiadomo?ci
...
Szczepan Bialek wrote:
If it were true, an antenna
would be a nonlinear element that would cause intermodulation. As we
don't see that happen on a well-designed antenna (it *does* happen
when
there are bad contacts with diode-effect in the antenna), we know that
an antenna by itself cannot be nonlinear and so there cannot be a net
flow of electrons.

The net flow of electrons is from the counterpoise to end of antenna.
S*

How do you explain that there is no intermodulation as a result of
the nonlinearity of the antenna that you claim?

I am here to learn.

Please don't wander off the subject and answer the question!
You did not answer the question why there is no intermodulation
in a transmitter antenna, while you claim it is nonlinear.

All is linear in the textbooks (necesary simplification).
In reality all is nonlinear.

Lately I have learn from Bilou:
"In such cases it is convenient to put the things to their limits.
Imagine the diameter of one half is infinite.
You now have a quarter wave over a ground plane.A well known case."

It means that a dipole fed from a coax is the monopole (a quarter wave)
with
the counterpoise.

"In the case of very rocky or poorly conducting soil a counterpoise often
is
substituted for a buried network of wires. A counterpoise is a network of
wires place above the earth a slight distance and insulated from it, so
arranged to produce a very high capacity to the earth."

So I know now why you all claim that a dipole do not need a ground.

Because a dipole does not need a ground, it is a symmetric antenna which
is not driven relative to ground.

Do you mean the antenna with the two legs where the one leg is connected to
the shield of a coax?

The number of radials is the power dependent. More power radiated more
electrons must be taken from a ground.
Do you agree?
S*

No.

For what are sometime the 120 radials?
S*