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Old May 6th 10, 09:25 AM posted to rec.radio.amateur.antenna
Szczepan Bialek Szczepan Bialek is offline
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First recorded activity by RadioBanter: Oct 2009
Posts: 707
Default What exactly is radio


"K1TTT" wrote
...
On May 5, 8:52 am, "Szczepan Bialek" wrote:

Wiki wrote: "The field can be viewed as the combination of an electric
field

and a magnetic field. The electric field is produced by stationary
charges,
and the magnetic field by moving charges (currents); "


an electric field can also be created by a changing magnetic field...

and a magnetic field by a changing electric field... no charges
needed.

In Maxwell's displacement current were charges (electricity).
In the space no charged bodies.

But what produce very slow charge?


a charge is a charge, it can neither be created nor destroyed.... well

except maybe by matter-anti-matter annihilation. charged particles
can move at any speed from 0 to c, nothing special about speeds.

Charged particles can move at any speed from 0 to c and always produce the
electric field. Why not?

Next Wiki weote: "From a classical perspective, the electromagnetic field

can be regarded as a smooth, continuous field, propagated in a wavelike
manner ;"

It is important to know that Maxwell's waves are rotational (oscillating

magnetic whirl).


no they aren't... at least not all of them. maxwells equations are

just as well satisfied by linearly polarized (magnetic AND electric
field) waves.

Maxwell's waves are transversal. It means that something oscillate around
the axis of rotation.
Linear polarization means thet the rotating oscillations are in the one
plane.

Alternate electric field also propagate in a wavelike manner. But here to

and fro (no rotations).


if the magnetic field is rotating then the electric field also

rotates. they always go together.

In Maxwell's Hypothesis.

The fundamental question: Are radio waves a simple electric waves or the
very sophisticated Maxwell's waves?


ALL radio waves can be described by maxwell's equations, both simple

linear polarized ones and circularly polarized ones.

Wiki wrote: " FM radio
The term "circular polarization" is often used erroneously to describe mixed
polarity signals used mostly in FM radio (87.5 to 108.0 MHz), where a
vertical and a horizontal component are propagated simultaneously by a
single or a combined array."

It seems that radio waves are the electric waves.
If yes, the light is also longitudinal.
S*