Current across the antenna loading coil - from scratch
 

Gene Fuller wrote:
... one value for the motion of a particle ...

Now I know you are pulling our legs. We are talking about
*electrons*, Gene, you know that "particle" capable of
going through two slits at the same time and interferring
with itself on the other side?

Please pick out just one electron and tell us what is
its position and velocity.
--
73, Cecil http://www.qsl.net/w5dxp

Current across the antenna loading coil - from scratch
 

Gene Fuller wrote:
Why didn't you set us straight about 3000 messages ago? If only we knew
that RF current was a mere artifact we could have shortened this thread
to one message.

Well Gene, that fact didn't occur to me 3000 messages ago so I
recently corrected my mistaken concepts. What do you do when you
discover a mistaken concept of your own? (rhetorical question)

Truth is, I'm still learning. How about you?
--
73, Cecil http://www.qsl.net/w5dxp

Current across the antenna loading coil - from scratch
 

Cecil Moore wrote:
Gene Fuller wrote:

So you think adding turns to a coil is a nice linear process that
allows you to then subdivide the resonance effects according the
number of turns in each subsection?


That appears to me to be the most valid measurement that we
can make of the delay through a coil. If you have a better
way, please present it.

Cecil,

C'mon, you know as well as anybody that inductance of a coil tends to
increase as n-squared. Yes, there are all kinds of special cases and
correction factors.

Adding turns and then pretending everything is nice and linear, thereby
allowing decomposition into subcomponents, is just plain silly.

73,
Gene
W4SZ

Current across the antenna loading coil - from scratch
 

Cecil, can I infer from your reply that you, too, can't find anything
in W8JI's original posting that refers to a lumped model?

With respect to your request, I suggest you re-read Tom's whole posting
and see if you can understand it. W8JI should perhaps have included in
the statement you quoted, "in and of itself/themselves," but certainly
it's accurate in the context from which you've extracted it. Certainly
you can have "current taper" along an antenna or along a TEM
transmission line for reasons other than loss to radiation or heating,
and ALL of them go right back to the very basics of what's going on in
an antenna and in a transmission line, and what Maxwell et al were
explaining with all their work.

Cheers,
Tom

Cecil wrote, in a posting for which the Usenet ID is available on
request,

K7ITM wrote:
Could you please enlighten us, Cecil, exactly why you think that
anything in all of W8JI's full posting referenced by reference below
where he implicitly or explicitly says anything at all about a lumped
model, or about lumped behaviour? After a careful search, I'm unable
to find it. I only find a discussion of distributed behaviour in a
circuit which extends beyond near field.

W8JI is right 99% of the time. I agree with him on those
things as do you. Your above posting is no surprise.

Here's one of W8JI's statements. Please defend it.

W8JI said:

Radiation does not cause current taper. Dissipation does not either.

What is contained in the attenuation factor for the current
transmission line equation if not radiation and dissipation?
What else is there?
--
73, Cecil http://www.qsl.net/w5dxp

Current across the antenna loading coil - from scratch
 

Richard Harrison wrote:
Gene, W4SZ wrote:
"However, the physical entities do not have two values at once in the
same time and place."

You can measure each of the two simultaneous constituents with the right
equipment. A Bird Thruline wattmeter uses a directional coupler to
separate forward direction power from reverse direction power. These are
obbtainable at the same time and place anywhere in a 50-ohm coax line.
Individual volts and amps in each direction are easily calcuable from
the powers indicated in each direction.

Best regards, Richard Harrison, KB5WZI


Richard,

You are in luck! This is Burger King day. Have it your way.

73,
Gene
W4SZ

Current across the antenna loading coil - from scratch
 

Gene Fuller wrote:
David G. Nagel wrote:


Tom

Have you ever sloshed water in a bowl? If you had you would have seen
wave forms going in both directions. First the initial wave crosses
the bowl then reflects off the side of the bowl and returns in the
opposite direction.
This is the same as an EMF wave in an antenna. No violation of any
principles of conservation, in fact it is demanded of the principle.

Dave WD9BDZ



Dave,

You have highlighted a misconception that is common and a great cause of
confusion in this forum.

Yes, the "waves" can do what you say. However, the "waves" are merely
mathematical descriptions of the underlying physical phenomena. There is
simply no such thing as a "wave" all by itself. Instead there are water
waves, electromagnetic field waves, guitar string waves, sound waves,
and so on.

Nature tends to be single valued, at least in the ordinary classical
world. At any specific point in time and space there is only one value
of current, one value of electric field, one value for the motion of a
particle (water molecule, guitar string molecule, etc.), one charge
density, and so on. These values can and do change with differences in
time and space. However, the physical entities do not have two values at
once in the same time and place.

73,
Gene
W4SZ

Now if we can only convince certain other individuals of this maybe we
can get back to something useful, such as how many angles can dance on
the head of a pin.

Dave WD9BDZ

Current across the antenna loading coil - from scratch
 

Cecil Moore wrote:
Gene Fuller wrote:

... one value for the motion of a particle ...


Now I know you are pulling our legs. We are talking about
*electrons*, Gene, you know that "particle" capable of
going through two slits at the same time and interferring
with itself on the other side?

Please pick out just one electron and tell us what is
its position and velocity.

Cecil,

I think I specifically mentioned the "ordinary classical world", but
I'll play along. Why don't you go ahead and measure that electron to
prove that it goes through both slits at once? 8-)

Current across the antenna loading coil - from scratch
 

Gene, W4SZ wroyte:
"However, the physical entities do not have two values at once in the
same time and place."

All that is needed to prove energy in the incident and reflected waves
each has its own values is to separate the two with a directional
coupler as the Bird Thruline wattmeter does. It gives you forward and
reverse powers at the same place anywhere you choose along a
transmission line. The standard device is calibrated for 50-ohm lines so
it is easy to convert the power indicationsw to volts and amps if
desired.

Take what Tom, W8JI wrote today:
"I take it you are saying you think current can flow in two directions
at the same instant of time in a conductor, can be "lost" from a single
conductor through radiation and resistance without a shunting impedance,
conservation of chrge isn`t important and Maxwell`s equations are
wrong."

Of course, except for Maxwell!

Maxwell`s equations work.

Current can flow in opposite directions past a point.

Shunting impedance makes a voltage divider with series impedance, but
that`s not the only way to get a difference between points on a
conductor or a coil.

Conservation of charge isn`t an issue with r-f current in a wire or
coil.

Tom`s posting is nonsense.

Best regards, Richard Harrison, KB5WZI

Current across the antenna loading coil - from scratch
 

Cecil, WHAT is your hangup about "lumped-circuit"?? W8JI-Tom, Tom
Donaly, Ian White, Roy Lewallen, Gene Fuller, Reg Edwards, I, and
others I can think of are NOT, repeat NOT, absolutely NOT, most
definitely NOT, talking about a lumped-circuit model. A lumped-circuit
model in general does NOT (repeat all the above emphasis) talk about
individual charge carriers, and individual charge carriers are NOT
required to talk about all the things we've been saying. Egad, man.

I will repeat, Maxwell et al were working to explain the forces acting
on charge, and the response of charge to those forces: the motion of
charge, the acceleration of charge, the accumulation of charge.
Fields, both electric and magnetic, are simply a mathematical and
useful way to represent the forces caused by all charges (in motion,
accelerated, at rest) on all other charges in the universe. Sometimes
fields as developed in classical electrodynamics fail to accurately
represent our observed reality, but they are still useful in describing
a great many of our everyday observations, and in solving
many--essentially all--of our everyday antenna problems.

I won't say it didn't happen at all, but I certainly can't recall in
any of these "discussions" getting down to considering individual
charged particles. We're dealing with effects accurately represented
by charge expressed as a continuum, distributed over space, with abrupt
boundaries at the edges of conductors assuming the forces aren't great
enough to rip free charge loose from the wires and form corona. We are
dealing with quanta in such overwhelmingly great numbers and such small
energy per quanta that there's no point in discussing them as quantized
charge or photons. No, we're dealing with a linear system that's
sufficiently accurately represented by a set of differential equations
that all get back eventually to the interaction of a continuous
distribution of charge, not a "lumped circuit" OR individual charged
particles, which are themselves very different thing, even though we
know that our distribution of charge is made up of such particles when
viewed on a fine enough scale.

So, PLEASE wake up and quit trying to attribute this "lumped circuit"
stuff, and the completely independent charge quantization stuff, to
this discussion. It simply is NOT there. It is absolutely NOT the
point of all this.

Cheers,
Tom


Cecil wrote in a posting whose Usenet ID is available on request,

K7ITM wrote:
Understanding the congrence among many methods/theories is a very nice
thing, for it gives one confidence that they are correct, and the
ability to apply the one that's most convenient to any particular
problem. I would not want to take away wave theory, or any other valid
theory, from you; I would only ask that you better understand that your
pet is not the ONLY valid explanation.

The point is that in any disagreement between the lumped-circuit
model and a properly applied distributed network model, the
lumped-circuit model loses *EVERY* time since the lumped-circuit
model is a *SUBSET* of the distributed network model.

If your current charge concepts disagree with Maxwell's equations,
Maxwell's equations win *EVERY* time. Maxwell's equations do not
require individual charge carriers. They work just fine considering
only fields in the aether.
--
73, Cecil http://www.qsl.net/w5dxp

Current across the antenna loading coil - from scratch
 

David G. Nagel wrote:
Tom Donaly wrote:

Richard Harrison wrote:

Tom, W8JI wrote:
"I take it you are saying you think current can flow two directions at
the same instant of time in a conductor through radiation and resistance
without a shunting impedance, conservation of charge isn`t important,
and Maxwell`s equarions are wrong."

That`s the wrong take.

Maxwell works for me even if there is no aether.

Anntennas work in free space without a ground but it is hard to
duplicate free space conditions at high and lower frequencies here on
earth.

Every standing-wave antenna has a reflection caused by an impedance
discontinuity at wire`s end. At this point, a reflection begins its
travel back toward the generator. By the time the reflection arrives at
the generator, every point on the wire has current flowing in both
directions simultaneously. No shunting capacitance to earth or anyplace
else is needed to conserve charge. The wire is self-sufficient.

Radiation resistance is a convenience defined as the resistance which if
placed in series with an antenna would consume the same power that the
antenna is radiating.

At every point along an antenna with a reflection, current is flowing in
two directions at the same time.

Best regards, Richard Harrison, KB5WZI



Completely wrong, as usual. There is nothing in the natural world
that can double itself and go two opposite directions at the same
time. In order to do so it would have to violate the principle of
the conservaton of charge. At any instant, the charge at a point
has to be going either one direction or another which you can
confirm using the wave equation which Cecil doesn't understand
any more than you do. Superposition is a fine principle, but
like any intellectual tool it has to be understood to be used
properly.
73,
Tom Donaly, KA6RUH


Tom

Have you ever sloshed water in a bowl? If you had you would have seen
wave forms going in both directions. First the initial wave crosses the
bowl then reflects off the side of the bowl and returns in the opposite
direction.
This is the same as an EMF wave in an antenna. No violation of any
principles of conservation, in fact it is demanded of the principle.

Dave WD9BDZ

Tell me which of the water molecules moved in two opposite directions
at the same time. The waves can move through each other in opposite
directions, but their combined influence is what moves the water
molecules. There are not two separate sets of water molecules that
flow in opposite directions, either. It's the combined total of
forces that causes the movement of both charge and water. Two opposite
movements of either charge or water are impossible.
73,
Tom Donaly, KA6RUH