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Old November 22nd 08, 08:33 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 Displacement current

On Nov 22, 1:14*pm, (Richard Harrison)
wrote:
Art wrote:

"So now one must determine where the reflection occurs and science
puports that it is not at the end of the antenna!"

Check your 1955 Terman opus. On page 887 is Fig. 23-24 showing current
on a 1/4-wave antenna. Current discontinues at the tip.

On page 893 Terman says:
"An antenna can therefore be regarded as a resonant system with
distributed constants. As a result, the impedance of an antenna behaves
in much the same manner as does the impedance of a transmission line
(see Sec. 4-7)."

Sec. (4-7) says on page 99:
"Similarly, with an open-circuited receiver, or with a resistance load
greater than the characteristic impedance so that the voltage
distribution of the open-circuit type (Fig.4-5),
the power factor is capacitive for lengths less than the distance to the
first minimum. Thereafter, the power factor alternates between
capacitive and inductive at intervals of a quarter wavelength, exactly
as in the short-circuited case.

If Cecil were asked where a reflection occurs on an antenna or a
transmission line, I`d wager he would reply, at the same place the
impedance discontinuity occurs.

Art has asked similar questions several times. Art should answer some
questions. What has his examination of Gauss` work produced that allows
quicker, more precise or easier answers to the problems readily solved
using Maxwell`s equations? What mistake has Art found in Maxwell`s
equations?

Best regards, Richard Harrison, KB5WZI


Ouch. Maxwell works O,.KJ for me. I use computer programs based on
Maxwell. Gauss gave me pointers that Maxwell failed to do i.e he never
gave a true account of radiation
or explained the role of the weak force.Thus I have to solve these
things for myself or follow the other lemmings
What I do not understand is not his thinking but the interpretation
that others place on his thinking. It is this I challkenge.
For instance all the masters stipulated the condition of equilibrium.
Somehow those very same equationsapparently missed
the equilibrium content in their equations. Maxwell came along and
placed an addfition to their combined formular. So how come this was
concieved to be necessary and is this connected to a ommision of
equilibrium portion of there observations? So Richard that should be
considered as a
answer to a question. I then changed Gauss law of statics by changing
it to a dynamic field following the stipulation of equilibrium.
Maxwells laws via computor programs provided an array in equilibrium
so Maxwell has included everything in his equations.
Absolutely no problems there. It also provided by the inclusion of
equilibrium that a radiaoir can be comprised of many shapes which to
me brings the helix antenna into the subject. That to me is a answer
to a question as to how helix antennas enter the picture. All of this
point to management of the edict of equilibrium . Now I am confronted
by those who believe that current only flows on the surface of a
radiatorwhich clashes with equilibrium. Then it is disclosed that the
Maxwell addition was a current that did not provide a magnetic field!,
another clash that does not follow the equilibrium edict tho a tank
circuit used as an equivalent of a full wave radiator has no open
circuit which again clashes with the thinking of this group. I am
suggesting various alternative thinking to these aberations because
they just don;'t jive. I believe I am answering questioins as to why I
look for alternatives it is others that refuse to supply acceptable
answerts that marry with my questions.Now to the present problem.
Maxwells additive to the equations have the units of cuurent such that
Newtons laws are satisfied. Previous thought was it was a reflection
of the impact of the aether which has now fallen into disfavour
so what do we put in its place? I gave that question to myself and
then provided effort to find a possible answer which I shared.
So Richard I am answering questions to the best of my ability which
includes explanations and not by clips uttered from booksthat are out
of date.
So you find it objectionable that I probe or challenge prior thinking
well........write to physics departments and wilkipedia and demand
retraction of the recent statement made on behalf of the Physics
community but don't just blame me as it is your generation that have
provided the present mix up as to what radiation is comprised of by
hanging on to sky hooks
Art