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Old July 9th 08, 09:37 PM posted to rec.radio.amateur.antenna
Art Unwin Art Unwin is offline
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First recorded activity by RadioBanter: Mar 2008
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On Jul 9, 10:43 am, (Richard Harrison)
wrote:
Art wrote:

"This states that when equilibrium breaks down current flows in the
CENTER of the conductor."

Fact is, only direct current flows in the center of the conductor
because alternating current makes more counter emf in the center of the
conductor than in the exterior. There are more total magnetic flux
linkages at the center and voltage is produced by the rate of change of
these linkages. So, current drnsity is greater as the external surface
of the conductor is approached.

Equilibrium is synonymous with balance or being at rest. An EM wave is
never at rest. A "balanced antenna" has equal capacitance to earth from
both of its feed terminals. Balanced and unbalanced antennas perform
equally well though in application one may be more suitable than the
other. A ground plane may be more easily fed by coax than a dipole but
both have the same power gain. There is no mystic advantage of
equilibrium in an electrical sense, only in contrived nonsense.

Best regards, Richard Harrison, KB5WZI


Sooner or later you will have to change your attitude. Terman was in
error by not including the WEAK force such that a radiator was tilted
and you are still clinging to his line of thought. Think about it
Originally I dampened my antenna by using the
pendulum as a equivalent mechanical example and you saw on my page the
resulting change in the oscillations.
Now you can do the opposite if you have a half wave antenna!. So what
has happened? The half wave is still resonant and the circuit has also
changed to a series circuit so we have lost the energy retention
propertes of the TANK circuit ! At the same time we must still retain
the closed system circuit which means the current must also travel
down the center of the radiator! Imagine that As an old ham who can't
change his ways you can create havoc about that.
Now when the charges move down the center of the radiator it cannot
provide eddy currents so the "skin" resistance is absent during that
part of the perioid.
Note by travelling down the center as a half wave it does not need a
counter poise because going down the center makes it a full wave
circuit.
Ofcourse for any other fraction of a wavelength you have to extent the
resistive portion of the center of the radiator in the form of radials
so that
the closed circuit is a wavelength or a multiple there of. Instead of
the radials in that case you can use instead a variometer so the
properties of wave length multiples are retained. Now if you can;'t
accept this simple logic ask somebody to use a antenna program to
determine the best angle for a vertical to attaim maximum vertical
radiation in the same terms that the masters intended with the correct
useage of their laws. Krauss did by finding the WEAK force
empirically even tho he did not understand why which was why the
helix radiating portion is at an angle with respect to the earths
surface.Note He also proved that a radiator need not be straight by
experimentation without resorting to Gauss when the dynamic extension
is applied
Use of any antenna computer program will produce this same angle with
straight radiators unless preguided to a planar form! So Richard,
saying it is a myth or a fraud is probably O.K. for you because of
your age, but for the younger engineers thay cannot afford not to
change and be left behind in the search of knoweledge. So no further
debate or auguements are necessary between you and I. And I will try
to remember to send flowers when the grim reaper appears at your door
where your position on antennas will matter no more while the rest
move on
and it is only the copper losses or resistance we have to deal with.
Richard, you can;'t mess with mother nature or the Universe