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Old December 10th 08, 05:06 PM posted to rec.radio.amateur.antenna
Art Unwin Art Unwin is offline
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First recorded activity by RadioBanter: Mar 2008
Posts: 1,339
Default skin depth (eddy current/Foucault currentO)

On Dec 10, 4:37*am, Ian White GM3SEK wrote:
Art Unwin wrote:
On Dec 6, 2:38*am, Ian White GM3SEK wrote:
JP wrote:


Skin depth and what cause it:


http://en.wikipedia.org/wiki/Skin_depth


The Wikipedia treatment is not incorrect, but it may create a false
impression that the skin effect is limited to some particular type or
cross-section of conductor.


There is a more general derivation by Davidson that has far fewer
restrictions about the assumed geometry. There is a scanned copy
at:http://www.ifwtech.co.uk/g3sek/misc/skin.htm


Davidson shows much more clearly that the existence of a skin effect
does not depend on any particular shape or size of conductor, or any
particular type of electrical circuit. If RF current is flowing in a
conductor - regardless of the reason - then the skin effect will be
present.


That is a very powerful conclusion. Because we know the skin effect will
be present, it helps us to trace the RF current pathways on complex
shapes such as coaxial cables and shielded loops.


--


73 from Ian GM3SEK * * * * 'In Practice' columnist for RadCom
(RSGB)http://www.ifwtech.co.uk/g3sek


Thank you very much for the addition supplied. I never really
understood why hams could not accept this
From my point oif view the beauty of the Foulcalt or eddy current is
without this "pealing" on the chemical adhesion effect
that a particle has on a diamagnetic surface the ejected particle
would be without spin, and as such would not be able to have straight
line
projection within a gravitational field, a necessity for radiation.
Any book on wave guides will picture this eddy current on the inside
walls
and any book on non destructive testing will also corroberate its
presence
and yet it is still rejected by this group. When Maxwell inserted the
required units to achieve equilibrium per Newton it was the
mathematics that forcast
the presence of a levitation force that would not be identified for
several decades but stil ignored because of the dominance of wave
theory.
Cheers
Art


I only just read this reply.

NOTHING that I have said or referenced supports Art's ideas in any way.
His ideas are totally deluded.

--

73 from Ian GM3SEK * * * * 'In Practice' columnist for RadCom (RSGB)http://www.ifwtech.co.uk/g3sek


Ian
I never stated that you supported anything with respect to my ideas.
What you supplied with respect to skin effect was a coroberation of
the Wilkpedia definition which I stated WAS correct
also in the face of a statement that said otherwise. And I thanked you
for supplying it and no more. You may call me delusional as a sample
of free speech but you like the others have never
supplied an iota of evidence that shows that my ideas have zero merit
and thus are indulging in childish attacks.
I know that you posses the AO antenna computer program and feel very
comfortable with the fact that you are capable of putting in a one
liner that shows
that a radiator for maximum efficiency will be devoid of parallelism.
Unless you initially guide a antenna optimiser towards a planar design
the program will respond with a non planar design That is a fact and
is not delusional. Statements like that is no more than support for
the many talking heads.
This is a ideal place to point out once and for all a basic fact that
points to the feasability of my analysis.To deny or try to cover up
this computor fact with respect to the avoidance of a planar design
because of the addition to general laws by Maxwell is understandable
by those who do not have the means to challenge the books is
understandable but for you there is absolutely no excuse and shows a
dependence on emotion while at the same time pushing aside scientific
fact a fact that that is undeniable. A planar design is a
approximation with respect to Maxwells laws. A antenna omptimisation,
if allowed, will always respond with a NON planar design to conform
with all aspects provided by Maxwell's laws which I might add includes
the addition iof the "weak" force as suspected by Einstein.
Art Unwin KB9MZ.........XG (uk)