Mike Coslo wrote:
Most of my measurements have been at
the self-resonant frequency of a loading coil.

That isn't the design frequency though, is it?

No, so I changed my approach. My present approach is to
take a self-resonant coil and use only part of the coil
on the *same* frequency, e.g. use half the coil as a loading
coil on the *same* frequency. That way, the velocity factor
should be roughly the same in either case.

I'm not sure I have this straight. I think I understand Tom's info,
yet this has me completely baffled.

I accept his magnitude measurements as probably accurate
and reasonable. His phase measurements were meaningless
since standing wave current phase doesn't change relative
to the source and therefore cannot be used to measure phase
shift along a wire or through a coil.

The standing wave current phase is the same from end to
end in a 1/2WL thin-wire dipole. It cannot be used to
determine the phase shift through a wire or a dipole. EZNEC
reports the same thing. This is key to understanding the
misconceptions involved and why the phase measurements were
meaningless.

Would the short answer be that you do not find any correlation?

*Nobody* has made a valid measurement of the delay through
a coil. There's nothing to correlate. One cannot use a signal
with unchanging phase to measure that delay.
--
73, Cecil http://www.qsl.net/w5dxp

Cecil Moore wrote:
Richard Clark wrote:
Neither Cecil nor Yuri made any measurements.

I made self-resonance measurements on loading coils
and standing wave current measurements on a 6m dipole.
W8JI said my measurements were in error. W7EL said
my measurements agreed with EZNEC.
--
73, Cecil http://www.qsl.net/w5dxp

Cecil, Cecil, Cecil! Shame on you. When will you ever quit changing
what other people say?

wrote:
Cecil Moore wrote:
I made self-resonance measurements on loading coils
and standing wave current measurements on a 6m dipole.
W8JI said my measurements were in error. W7EL said
my measurements agreed with EZNEC.

Cecil, Cecil, Cecil! Shame on you. When will you ever quit changing
what other people say?

Replying to my measurements, here are your words and W7EL's words:

W8JI wrote on 3-16-06:
Your measurements are probably wrong. ... After we resolve the
error in current, we can move on.

I repeat: "W8JI said my measurements were in error."

W7EL replied on 3-16-06:
The measurement looks good to me. The phase is exactly what EZNEC
predicts -- constant along the wire.

I repeat: "W7EL said my measurements agreed with EZNEC."

begin quote of entire posting from 3-16-06:
************************************************** ********************
wrote:

Cecil Moore wrote:

Note that at the frequency where the dipole is 1/2WL and resonant,
it is 180 feet long and 180 degrees long so the number of feet of
wire is also the number of degrees of antenna. Here is my 1/2WL
dipole with current pickup coils installed at points 'x' and 'y' and
FP is the feedpoint,the impedance of which is 60 ohms.

------------------------------FP-------x---------------y-------

Total length is 180 feet. The distance between 'x' and 'y' is 45 feet.
Since feet = degrees in this case, the number of degrees between
'x' and 'y' is known to be 45 degrees from antenna theory. Those
45 degrees are what I am going to attempt to replace with a coil.

So I adjust the feedpoint current to one amp at a reference phase
angle of zero degrees and measure the current at 'x' and the current
at 'y'. The current at 'x' is 0.92 amp at 0 deg. The current at 'y' is
0.38 amp at 0 deg. Already I am not understanding my measurements.


Your measurements are probably wrong.

When did you measure that? After we resolve the error in current, we
can move on.


The measurement looks good to me. The phase is exactly what EZNEC predicts
-- constant along the wire. The ratio in magnitudes we'd expect depends on
the positions along the wire, not just the spacing.

Roy Lewallen, W7EL
************************************************** ************************

Cecil Moore wrote:
Gene Fuller wrote:

Gene Fuller wrote:

Cecil Moore wrote:

Actually, it's just the other way around. How is one ever
going to understand what's really going on by superposing
waves to the point where half the information is lost?


That question explains everything. It demonstrates conclusively that
you no understanding of superposition.

It also demonstrates that I can't proofread two sentences.


Take two PSK signals, superpose them through the same coax,
and see how much information is lost.

Cecil,

Strike two!

More demonstration that you don't understand superposition.

73,
Gene
W4SZ

Gene Fuller wrote:
Cecil Moore wrote:
Take two PSK signals, superpose them through the same coax,
and see how much information is lost.

Strike two!
More demonstration that you don't understand superposition.

Actually, more demonstration that you shy away from technical
discussions in favor of inuendo. One wonders why? Please feel
free to enlighten me and others about how phase is conserved
during the superposition process.
--
73, Cecil http://www.qsl.net/w5dxp

Cecil Moore wrote:
Gene Fuller wrote:

Cecil Moore wrote:

Take two PSK signals, superpose them through the same coax,
and see how much information is lost.


Strike two!
More demonstration that you don't understand superposition.


Actually, more demonstration that you shy away from technical
discussions in favor of inuendo. One wonders why? Please feel
free to enlighten me and others about how phase is conserved
during the superposition process.

Cecil,

There is nothing in the concept of superposition that will prevent you
from munging up something. I have no idea how you are planning to
"superpose" two signals through the same coax, and therefore I have no
idea what might happen to the phase.

Go back and review what superposition means. I have stated it here
before. It is a standard concept presented in many math, science, and
technology textbooks. In simplified form, when superposition applies it
says that the output from the combination of two inputs is the same as
the sum of the outputs from each input taken one at a time. This is
precisely what allows all of the various authors to say that one can
consider a standing wave to be equivalent to two opposite direction
traveling waves. This is purely a mathematical notion; superposition
does not impact the physical reality at all.

Superposition does not always apply. Only systems that are linear can be
expected to exhibit superposition properties.

If you choose to add a second input that was not there previously then
the combined output will be different than the output from the original
single input.

I didn't know I shied away from technical discussions. I thought you
were quoting me as one of your gurus when it was convenient.

73,
Gene
W4SZ

Gene Fuller wrote:
In simplified form, when superposition applies it
says that the output from the combination of two inputs is the same as
the sum of the outputs from each input taken one at a time.

The point is that phase is not preserved through the superposition
process and as you have noted before, the phase information completely
disappears from the superposed standing wave current.

This is
precisely what allows all of the various authors to say that one can
consider a standing wave to be equivalent to two opposite direction
traveling waves. This is purely a mathematical notion; superposition
does not impact the physical reality at all.

It certainly impacts the physical reality of W7EL's phase measurements.
If he measured the delay through the coil using the forward current,
he would obtain valid results. If he measured the delay through the
coil using the reflected current, he would obtain valid results. But
the superposition of those two currents results in a signal with
unchanging phase that cannot validly be used to determine the delay
through a wire or a coil or anything else.

I thought you
were quoting me as one of your gurus when it was convenient.

Yes, because you agree with me on most technical points. Your arguments
with me are invariably personal, not technical. I am not aware of a
single technical point upon which you and I disagree.
--
73, Cecil http://www.qsl.net/w5dxp

Cecil Moore wrote:
Gene Fuller wrote:

I thought you were quoting me as one of your gurus when it was
convenient.


Yes, because you agree with me on most technical points. Your arguments
with me are invariably personal, not technical. I am not aware of a
single technical point upon which you and I disagree.

Cecil,

Be assured that I disagree with you on a great many technical points.

8-)

73,
Gene
W4SZ

Gene Fuller wrote:
Be assured that I disagree with you on a great many technical points.

Name one.
--
73, Cecil http://www.qsl.net/w5dxp