November 1st 14, 11:44 PM
posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Jun 2006
Posts: 1,898
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No antennae radiate all the power fed to them!
rickman wrote:
On 11/1/2014 6:20 PM, wrote:
gareth wrote:
"Brian Reay" wrote in message
...
He is confusing the current and voltage distribution plots for waves.
No, there is no confusion on my part. Please explain why you think
that, for I fear that there may be confusion on your part.
Plus,
an RF wave has a magnetic component.
Well, i think we all knew that.
That can't exist IN the antenna
element as it is conductor.
Yes, and no, for it is the magnetic componentry in the wire
that causes the skin effect.
Magnetic fields can exist in a conductor.
Electromagnetic fields can not exist in a conductor.
Now I'm very confused. How can an EM field not exist in a conductor?
Isn't it the E part that creates a gradient which propels the electrons?
Actually it is both.
As long as the antenna is made of linear material, transmit and receive
are reciprocal properties.
The only antennas I can think of that use non-linear materials is some
microwave antennas that include ferrites.
In a perfect conductor, I thought it was the M part that can't exist
inside the conductor. That is one of the causes of the loss of
superconductivity, penetration by an M field. Or do I have this mixed up?
A bit.
--
Jim Pennino
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