Jim Kelley wrote:
Since a standing wave is an interference pattern created by traveling
waves, having 'only standing waves' would obviously be an impossible
circumstance.

Nonsense. All it takes is two identical waves traveling in
opposite directions along the same path. Such happens at the
open-circuit or short-circuit point in a 1/4WL stub.

I urge you to please investigate the mathematical issues associated with
summing counter-rotating vectors.

I have, Jim. It is you who seems confused. If two coherent
phasors of equal amplitudes and opposite rotations are
phasor-added, the resulting total phase is a constant.

1 at zero deg + 1 at zero deg = 2 at zero deg
1 at 45 deg + 1 at -45 deg = 1.4.4 at zero deg
etc.

Correct me if I'm wrong, but as far as I know you are the only one
suggesting that standing wave current phase - whatever that is - could
be delayed, measured, and calculated.

Nonsense, Jim, standing wave current phase is what EZNEC
reports for a standing-wave antenna.

If you are incapable of comprehending, don't feel bad.
My dog doesn't understand it either but I still love her.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

Jim Kelley wrote:
Since a standing wave is an interference pattern created by traveling
waves, having 'only standing waves' would obviously be an impossible
circumstance.

Time to hit the books, Jim. Standing waves are described
in Born and Wolf, section 7.4, pages 297-281, 4th edition.

"We see that at each instant in time the *phase is constant*
through the first medium." The first medium is where the
pure standing waves are. Born and Wolf agree that the phase
of the standing wave doesn't change throughout the medium.
Therefore, its phase cannot be used to measure delay.

The same material is covered in "Optics", by Hecht, section
7.1.4, pages 288-293, 4th edition.

"[Standing wave phase] "*doesn't rotate* at all, and the
resultant wave it represents doesn't progress through space -
its a standing wave."

If you are incapable of understanding that material,
I'm afraid I cannot help you.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

On Apr 16, 9:48*pm, Cecil Moore wrote:
Art Unwin wrote:
Both sides should be able to understand what the other is saying!

Don't worry about it, Art. My dog doesn't understand
it either.
--
73, Cecil, IEEE, OOTC, *http://www.w5dxp.com

I don't worry about it Cecil but I am concerned at the number of
people who consider themselves engineers. Remember that nobody on this
group has a true understanding of Maxwells equations! Nobody has
proved Maxwell's laws can be proved by adding a time varing field to
the Gaussian law of Statics. In fact, it is denied by ALL on this
group, Engineers?
That to even try is illegal as well as not being correct! Real
qualified engineers?
And you want this group to understand phase change and travelling
waves without the group coming to a consensus on Maxwell's laws?
Especially when they demand
a definition of equilibrium?
Maxwell;'s laws do not include lumped loads in his equations for
maximum radiation efficiency, so why do hams use lumped loads with
their antennas?
Maxwell;'s laws demand that for maximum efficiency equilibrium must be
kept, yet hams continue to place verticals at right angles to the
earth's surface. And it goes on and on. And engineers continue to
misuse what is known as Maxwell's equations.
However, despite that I do have a honest question Does the TOA of a
dish antenna (CP) change with height similar to other polarisations?
Regards
Art

Since a standing wave is an interference pattern created by traveling
waves, having 'only standing waves' would obviously be an impossible
circumstance.

By "only standing waves", I meant pure standing
waves and nothing else.

We've been through this one before. If the SWR
is 1:1, there is only a forward traveling wave.
If the SWR is not 1:1, there exists a forward
traveling wave and a reverse traveling wave.
If the SWR is infinite, the amplitudes of the
forward wave and reflected wave are equal and
a pure standing wave is the result.

"Only standing waves" doesn't mean the underlying
traveling waves don't exist. It simply means that
the amplitudes of the forward wave and reflected
wave are equal and therefore all of the energy
components in the traveling waves have combined
into the standing waves.

For instance, a lossless stub would contain "only"
standing waves, i.e. pure standing waves.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

Cecil Moore wrote:
Jim Kelley wrote:
Why not just measure the delay in the instantaneous arrival of energy?

Why make something difficult out of a simple
problem?

My question precisely.

How can you tell one packet of energy
from another?

It's easier than distinguishing one cyle of a sine wave from another.

Please do the measurement if you
choose and report back what you find.

Just send the coil you would like me to test. I'd be pleased to do it
for you and report back.

ac6xg

Cecil Moore wrote:
Since a standing wave is an interference pattern created by traveling
waves, having 'only standing waves' would obviously be an impossible
circumstance.

By "only standing waves", I meant pure standing
waves and nothing else.

There is still no circumstance where you can have standing waves and
nothing else. It's a ridiculous thing to say.

We've been through this one before. If the SWR
is 1:1, there is only a forward traveling wave.
If the SWR is not 1:1, there exists a forward
traveling wave and a reverse traveling wave.
If the SWR is infinite, the amplitudes of the
forward wave and reflected wave are equal and
a pure standing wave is the result.

"Only standing waves" doesn't mean the underlying
traveling waves don't exist. It simply means that
the amplitudes of the forward wave and reflected
wave are equal and therefore all of the energy
components in the traveling waves have combined
into the standing waves.

For instance, a lossless stub would contain "only"
standing waves, i.e. pure standing waves.

'Pure standing wave' is a more useful term. But there is no
circumstance under which there is "only" a standing wave.

Borrowing from your favorite pro forma rhetorical question: what part of
'interference pattern' don't you understand?

ac6xg

Cecil Moore wrote:
Jim Kelley wrote:
Since a standing wave is an interference pattern created by traveling
waves, having 'only standing waves' would obviously be an impossible
circumstance.

Time to hit the books, Jim. Standing waves are described
in Born and Wolf, section 7.4, pages 297-281, 4th edition.

"We see that at each instant in time the *phase is constant*
through the first medium." The first medium is where the
pure standing waves are. Born and Wolf agree that the phase
of the standing wave doesn't change throughout the medium.
Therefore, its phase cannot be used to measure delay.

The same material is covered in "Optics", by Hecht, section
7.1.4, pages 288-293, 4th edition.

"[Standing wave phase] "*doesn't rotate* at all, and the
resultant wave it represents doesn't progress through space -
its a standing wave."

If you are incapable of understanding that material,
I'm afraid I cannot help you.

I understand it well enough to note that it fails to make your point for
you. However it does clearly make a point that has never been in
contention. Bravo.

(Evidently you've forgotten that I was the person who introduced you to
Born and Wolf in the first place.)

ac6xg

Jim Kelley wrote:
Cecil Moore wrote:
How can you tell one packet of energy
from another?

It's easier than distinguishing one cyle of a sine wave from another.

Certainly not true if one knows the device under test
is shorter than one wavelength. I have measured a lot
of voltage circuit delays. I have never measured an
energy delay, whatever that is.

Just send the coil you would like me to test. I'd be pleased to do it
for you and report back.

Pick any old air-core in the 50-100 uH range. 20 turns
of #16 wire on a 2L pop bottle should do the trick.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

Jim Kelley wrote:
There is still no circumstance where you can have standing waves and
nothing else. It's a ridiculous thing to say.

It was a colloquial choice of words which I previously
defined as meaning exactly the same thing as "pure
standing wave".

If I say, "There's nothing but bicycles on this
road today", would you say that's ridiculous because
there is also dirt on the road? (Yes, you would).

'Pure standing wave' is a more useful term.

If that will keep your panties from getting bunched
up, I am all for it.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

Cecil Moore wrote:
Jim Kelley wrote:
Since a standing wave is an interference pattern created by traveling
waves, having 'only standing waves' would obviously be an impossible
circumstance.

Nonsense. All it takes is two identical waves traveling in
opposite directions along the same path. Such happens at the
open-circuit or short-circuit point in a 1/4WL stub.

Here we have an excellent illustration of the kink in your understanding
of wave phenomena. Because just as interference does not cause waves to
reflect, waves do not make other waves do things, or turn into something
else. A standing wave interference pattern is a result of the presence
of traveling waves. One does not replace the other.

I urge you to please investigate the mathematical issues associated
with summing counter-rotating vectors.

I have, Jim. It is you who seems confused. If two coherent
phasors of equal amplitudes and opposite rotations are
phasor-added, the resulting total phase is a constant.
1 at zero deg + 1 at zero deg = 2 at zero deg
1 at 45 deg + 1 at -45 deg = 1.4.4 at zero deg
etc.

I you were producing numbers which made sense and were correct, we
wouldn't be having this discussion, Cecil. A wave is at various phases
along it's length. The phase varies from 0 to 360 every complete cycle.
This includes standing waves. Its phase is not "zero" at every point.
It's ridiculous to have to point this out to a self proclaimed "expert"
on any and every subject such as yourself.

Correct me if I'm wrong, but as far as I know you are the only one
suggesting that standing wave current phase - whatever that is - could
be delayed, measured, and calculated.

Nonsense, Jim, standing wave current phase is what EZNEC
reports for a standing-wave antenna.

In my experience, incorrect assumptions produce incorrect results. The
EZNEC results you refer to are an archetypal example of the effect.

ac6xg