Richard Clark wrote:
Not valid is quite different from invalid.

What is your native language? :-) From Webster's:
"in - a prefix ... having a negative force"

Seeing that
Cecil wholeheartedly has yet to reveal the how (or data to the same
precision) of his own counter experiment (which I have also gone on
record in asking for details) - I don't expect anything there either.

Good grief, Richard, I posted a detailed description of those
measurements more than a year ago before I moved to my new QTH.
In words, with a 50 ohm source, set up an autotransformer to
deliver a signal to a 3600 ohm Z0 environment. Put the 75m Texas
Bugcatcher coil in series with a 3600 ohm non-inductive load.
Measure the phase shift through the coil at 4 MHz. I eyeballed
it at ~25 degrees on a dual-trace 100 MHz O'scope.
--
73, Cecil http://www.w5dxp.com

On Mon, 03 Dec 2007 23:23:45 GMT, Cecil Moore
wrote:

In words, with a 50 ohm source, set up an autotransformer to
deliver a signal to a 3600 ohm Z0 environment. Put the 75m Texas
Bugcatcher coil in series with a 3600 ohm non-inductive load.
Measure the phase shift through the coil at 4 MHz. I eyeballed
it at ~25 degrees on a dual-trace 100 MHz O'scope.

And what was it when you cut the coil in half?

Richard Clark wrote:
Cecil Moore wrote:
In words, with a 50 ohm source, set up an autotransformer to
deliver a signal to a 3600 ohm Z0 environment. Put the 75m Texas
Bugcatcher coil in series with a 3600 ohm non-inductive load.
Measure the phase shift through the coil at 4 MHz. I eyeballed
it at ~25 degrees on a dual-trace 100 MHz O'scope.

And what was it when you cut the coil in half?

I apologize, Richard, like W8JI, I am unwilling to cut my
75m Texas bugcatcher coil in half. But then, his coil didn't
cost $180 either. :-)

The experiment that you are suggesting is exactly the same
that I suggested to W8JI but he was unwilling to perform
such and I tend to understood why. :-)

As a data point, in the previous argument a couple of years
ago, W8JI tried to use the lumped inductance feature of EZNEC
to "prove" there is never any phase shift through any coil. :-)
--
73, Cecil http://www.w5dxp.com

On Tue, 04 Dec 2007 00:31:02 GMT, Cecil Moore
wrote:

I apologize, Richard, like W8JI, I am unwilling to cut my
75m Texas bugcatcher coil in half. But then, his coil didn't
cost $180 either. :-)

The experiment that you are suggesting is exactly the same
that I suggested to W8JI but he was unwilling to perform
such and I tend to understood why. :-)

As a data point, in the previous argument a couple of years
ago, W8JI tried to use the lumped inductance feature of EZNEC
to "prove" there is never any phase shift through any coil. :-)

So, the short of it (the long of it is above) is that neither of you
have valid data that demonstrates a Corum solution. I'm not
surprised.

Seeing that there is no valid conclusion, it must be by the extended
logic of your understanding of English that both your and Tom's
positions are thus INVALID.

Anything left to introduce, barring actual test results, is not
superposition, but supposition.

Richard Clark wrote:
So, the short of it (the long of it is above) is that neither of you
have valid data that demonstrates a Corum solution. I'm not
surprised.

In addition to my measurements on the 75m Texas
Bugcatcher coil, I also measured ~12-13 ns delay
through 50 turns of the same coil stock that Tom
was using when he measured a 3 ns delay through
a 100 turn coil. That 12-13 ns delay is within
15% of the Corum equation predictions.
--
73, Cecil http://www.w5dxp.com

On Tue, 04 Dec 2007 19:16:01 GMT, Cecil Moore
wrote:

I also measured ~12-13 ns delay
through 50 turns of the same coil stock that Tom
was using when he measured a 3 ns delay through
a 100 turn coil. That 12-13 ns delay is within
15% of the Corum equation predictions.

Using what equipment? And with what load?

Richard Clark wrote:
Cecil Moore wrote:

I also measured ~12-13 ns delay
through 50 turns of the same coil stock that Tom
was using when he measured a 3 ns delay through
a 100 turn coil. That 12-13 ns delay is within
15% of the Corum equation predictions.

Using what equipment? And with what load?

Equipment was a dual-trace 100 MHz O'Scope. If I
remember correctly, the load was four 600 ohm non-
inductive resistors in series. My notes are in a
box somewhere.
--
73, Cecil http://www.w5dxp.com

Richard Clark wrote in
:

On Mon, 03 Dec 2007 23:23:45 GMT, Cecil Moore
wrote:

In words, with a 50 ohm source, set up an autotransformer to
deliver a signal to a 3600 ohm Z0 environment. Put the 75m Texas

I can't see why an attempt to impedance match the source was necessary,
the reflection coefficient is determined solely by the load and line
characteristics.

Bugcatcher coil in series with a 3600 ohm non-inductive load.
Measure the phase shift through the coil at 4 MHz. I eyeballed
it at ~25 degrees on a dual-trace 100 MHz O'scope.

If you were confident that reflection was insignificant, then this test
design might properly reveal the one way delay of the transmission line
section.


And what was it when you cut the coil in half?


Sampling the forward wave (which should be the dominant wave if with an
approximatly matched load) at various points and comparing phase (wrt
source) with displacement might establish if the apparent phase velocity
is constant.

I don't suspect that the outcome of a properly designed and executed
experiment is going to surprise anyone.

Interesting as the answer is, the question still remains, what can one do
with the knowledge of the one way delay of a short loading coil when
designing a loaded monopole?

Owen

Owen Duffy wrote:
I can't see why an attempt to impedance match the source was necessary,
the reflection coefficient is determined solely by the load and line
characteristics.

This may (or may not) be a source of misunderstandings on this
newsgroup. If the source is not matched to the characteristic
impedance of the environment, then reflections result, even if
they are "same-cycle" reflections. That leads to such concepts
as unchanging phase all around the circuit in violation of the
rules for distributed networks.

Ask yourself this question: One inch away from a mismatched load
at HF frequencies, do reflections exist? If your answer is "no",
it is time to question your concepts. If your question is "yes",
then the same thing happens when the load is one inch away from
the source. Think about that.

If you were confident that reflection was insignificant, then this test
design might properly reveal the one way delay of the transmission line
section.

The goal in this type of measurement is to reduce the reflections
to a manageable level. If one recognizes what one is observing, one
can "see" the forward waves when the standing wave is half of
the total waveform. Ideally, the reflections would be eliminated,
but that is not an absolutely necessity.

I don't suspect that the outcome of a properly designed and executed
experiment is going to surprise anyone.

I can guarantee you it will be a total surprise to most of the
omniscient "gurus" on this newsgroup who will deny its validity.
If you side with the technical results of such an experiment, you
will be labeled a mentally disabled kook or worse.
--
73, Cecil http://www.w5dxp.com

Cecil Moore wrote:

Richard Clark wrote:

Not valid is quite different from invalid.


What is your native language? :-) From Webster's:
"in - a prefix ... having a negative force"

If I've learned anything from you Cecil, it's that the writer gets to
choose which definition he tends, or intends, whatever the case may
be. Perhaps your emphasis is on the wrong syllable. :-)

73, ac6xg