Cecil,

There is complete contradiction between the physics you have concocted
and the real world.

I perfectly understand your concepts. They are great for explanations
and handwaving, but little else.

Until you understand the basics of the first few chapters in any physics
(E&M) textbook there is no hope for agreement. Little more for me to say.

73,
Gene
W4SZ

Cecil Moore wrote:
Gene Fuller wrote:

I cannot speak directly for Tom Donaly, but you and I are about 99% in
DISagreement over physics.


That's just a straw man, Gene. You school and my school probably
taught 99% the same physics. You and I are not that far apart at
all. THERE ARE NO CONTRADICTIONS BETWEEN THE PHYSICS YOU USE AND
THE CONCEPTS I AM PRESENTING. It only appears that way to you
because you haven't taken the time to understand those concepts.

Are there standing waves on a standing wave antenna? Are standing
waves caused by the superposition of forward and reflected waves?
Absolutely nothing new or different there.

Current, charge, voltage, E-field, and H-field are different physical
entities. They are related, but they are not interchangeable.


Straw man alert! I resent any implication that I said they were
interchangeable. I agree with you about the above quantities.

No amount of E-field, H-field, or voltage can create or destroy charge.


Straw man alert! I resent any implication that I said charge could
be destroyed. I agree with what you said about charge.

Current is the movement of charge. At any point in space that charge
must either keep moving (Kirchhoff's current law) or it must be stored
(continuity equation). There is absolutely no other choice, period.


EXACTLY! And that is exactly what you and W8JI are missing. The familiar
cosine current distribution on a dipole is a standing wave, i.e. the net
current in that standing wave is not moving. Therefore, the net current
doesn't obey your rules above. The net current is just an artifact of
superposition of the forward current wave with the reflected current
wave. It is the forward current and reflected current that is moving.
Until you and Tom understand the nature of standing-wave antennas, you
will never understand the nature of the current(s) through a loading
coil installed in the middle of a standing wave antenna.

Kurt N. Sterba made the same mistake in this month's Worldradio article.
In a standing-wave antenna, the net current doesn't flow and RF current
cannot stand still. The current is zero at the tip of a standing wave
antenna not because all the energy has been radiated and/or conducted
away by displacement currents. The current is zero because all the
energy at that point is contained in the E-field. The forward H-field
and the reflected H-field cancel each other at the tip of a standing
wave antenna. If you really think there is zero energy at the tip of
a mobile antenna, please grab it while power is applied.

Your traveling wave/standing wave model is intuitive, but otherwise
useless.


Until you take the time to conceptually understand standing wave
antennas, there is absolutely no chance of you understanding what
happens when a loading coil is inserted in a standing wave antenna.

If so, then it is likely that Balanis is merely trying to tie the
entire world of antennas together to give a warm and fuzzy feeling to
the reader.


If what Balanis said is false, please present some proof.

Do you have a reference to an analytic treatment using the traveling
wave model that could give results comparable to NEC2? If so, I would
sure like to find that reference.


There are some problems that do not lend themselves very well to a
quantitative analysis. That's why simulation modeling is so popular with
antennas and Blackjack.

However, the difficulty of a quantitative analysis should not turn your
brain into concrete such that you reject the associated qualitative
analysis. All of these qualitative concepts are presented in textbooks.
I have only quoted a handful of them.
--
73, Cecil, W5DXP