Standing waves
"Richard Fry" wrote
...
On Sep 21, 12:23 pm, Szczepan Białek wrote:
You only do not realize that EM waves can start from the ELECRIC field.
The
electric field is radiated from the ends where is high voltage and no
current.
No, Szczepan, it is you that does not realize that voltage, alone,
cannot produce an
Let us assume that electromagnetic field is a proposition by Maxwell.
The electric field is more realistic.
Only the change in current and charge flowing along a conductor, over
time, produces far-field EM radiation. That radiation includes both
the magnetic and electric fields, at right angles to each other and to
the direction of travel.
It is untrue that one part of a conductor or antenna radiates the
magnetic field, and another part radiates the electric field, no
matter the claims of the proponents of the E-H antenna (which have not
been demonstrated).
But it is experimentally proved. Stationary charge - electric field, Moving
charge - magnetic field.
Probably the both fields are the same. Only instruments are different.
The fact that the ends of a dipole, and the top of a monopole have
very little net current flowing means that those locations cannot
contribute very much to the EM radiation from those antennas.
But there are the doubled voltage. Very strong pulses must appear in space.
You really should form your opinions from research in modern textbooks
on antennas, rather than using Wikipedia and inapplicable analogies to
sound waves. At a minimum you could recognize the quotes from them on
this subject that already have been posted here.
Up to now the acoustic analogy is fully applicable.
S*
RF
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