"Gene Fuller" wrote:
Phase is gone. Kaput. Vanished. Cannot be recovered. Never to be seen
again.

So how can a signal, devoid of phase, be used to measure the phase
shift through a loading coil?

The only "phase" remaining is the cos (kz) term, which is really an
amplitude description, not a phase.

How can one make a phase measurement using only the amplitude
of a signal?
--
73, Cecil, W5DXP

Cecil Moore wrote:
"Gene Fuller" wrote:

Phase is gone. Kaput. Vanished. Cannot be recovered. Never to be seen
again.


So how can a signal, devoid of phase, be used to measure the phase
shift through a loading coil?


The only "phase" remaining is the cos (kz) term, which is really an
amplitude description, not a phase.


How can one make a phase measurement using only the amplitude
of a signal?
--
73, Cecil, W5DXP



Cecil,

The phase is uniformly zero, so the phase shift is also zero.

Your messages seem to imply that there is some sort of characteristic
"phase shift" in a loading coil. Ain't so.

In the example of a standing wave antenna the phase shift is zero, both
experimentally and theoretically. (Approximate. Real world conditions
might cause small non-zero shifts.)

If you place this same loading coil in a traveling wave antenna you can
undoubtedly measure some sort of phase shift. (Exact amount left as an
exercise for the student.)

Bottom line: Any characteristic, such as phase, that explicitly depends
on the wave nature of a signal needs to be referenced to that condition,
not some arbitrary setup.

73,
Gene
W4SZ

Gene Fuller wrote:

Cecil,

The phase is uniformly zero, so the phase shift is also zero.

Your messages seem to imply that there is some sort of characteristic
"phase shift" in a loading coil. Ain't so.

In the example of a standing wave antenna the phase shift is zero, both
experimentally and theoretically. (Approximate. Real world conditions
might cause small non-zero shifts.)

If you place this same loading coil in a traveling wave antenna you can
undoubtedly measure some sort of phase shift. (Exact amount left as an
exercise for the student.)

Bottom line: Any characteristic, such as phase, that explicitly depends
on the wave nature of a signal needs to be referenced to that condition,
not some arbitrary setup.


It's likely that quite a number of people don't realize that there's no
phase shift of current or voltage along a short or open circuited
lossless transmission line -- except for, like on an antenna, periodic
polarity reversals.

Roy Lewallen, W7EL

"Roy Lewallen" wrote:
It's likely that quite a number of people don't realize that there's no
phase shift of current or voltage along a short or open circuited
lossless transmission line -- except for, like on an antenna, periodic
polarity reversals.

If we have 45 degrees of transmission line and measure no phase
shift at each end of that 45 degrees, does that mean the transmission
line is really zero degrees long?

If we have an unknown number of degrees of coil and measure
no phase on each side of the coil, does that mean the coil is
really zero degrees long?
--
73, Cecil, W5DXP

"Gene Fuller" wrote:..
Your messages seem to imply that there is some sort of characteristic
"phase shift" in a loading coil. Ain't so.

Thanks, Gene. What was implied is what has been reported as fact
by others - that the zero phase shift on both ends of a loading coil
measures the delay through the coil to be close to zero.

In the example of a standing wave antenna the phase shift is zero, both
experimentally and theoretically. (Approximate. Real world conditions
might cause small non-zero shifts.)

Please note that the phase shift in the wire is also zero. That the phase
shift is measured to be zero in a coil or a wire in a standing wave
environment is not of any practical importance whatsoever.

If you place this same loading coil in a traveling wave antenna you can
undoubtedly measure some sort of phase shift. (Exact amount left as an
exercise for the student.)

That was the discussion involving Dr. Corum's papers and the VF of
large RF inductors, like a 75m bugcatcher coil.
--
73, Cecil, W5DXP

Cecil,

You're a sly one, but not quite sly enough. 8-) 8-)

What is the meaning of "delay" in a standing wave antenna? Delay, like
phase, depends on the environment.

The measurement results reported by W8JI a few days ago stand on their
own. He described the setup and measurements adequately.

If you choose to make extrapolations to another environment, have at it.
Just don't expect anyone else to automatically agree with your
extrapolations.

As I recall, this three-year saga started with consideration of a loaded
mobile antenna, which I believe would be considered a standing wave
antenna. Have you since equipped your steed with a Beverage or rhombic?
Are phase shifts and delays now important?

73,
Gene
W4SZ


Cecil Moore wrote:
"Gene Fuller" wrote:..

Your messages seem to imply that there is some sort of characteristic
"phase shift" in a loading coil. Ain't so.


Thanks, Gene. What was implied is what has been reported as fact
by others - that the zero phase shift on both ends of a loading coil
measures the delay through the coil to be close to zero.


In the example of a standing wave antenna the phase shift is zero, both
experimentally and theoretically. (Approximate. Real world conditions
might cause small non-zero shifts.)


Please note that the phase shift in the wire is also zero. That the phase
shift is measured to be zero in a coil or a wire in a standing wave
environment is not of any practical importance whatsoever.


If you place this same loading coil in a traveling wave antenna you can
undoubtedly measure some sort of phase shift. (Exact amount left as an
exercise for the student.)


That was the discussion involving Dr. Corum's papers and the VF of
large RF inductors, like a 75m bugcatcher coil.
--
73, Cecil, W5DXP

Gene Fuller wrote:
What is the meaning of "delay" in a standing wave antenna?

Same as in a traveling wave antenna - the length of
time it takes a traveling wave signal to make it through
a coil or a wire. The lumped-circuit model assumes that
delay is equal to zero even for traveling wave antennas.

Delay, like phase, depends on the environment.

I defined what I meant by "delay" through a coil a few days
ago. It was the delay experienced by a traveling wave
flowing through a coil or 1/2 the delay experienced by
a traveling wave making a round trip to the end of a coil
and back based on the self-resonant frequency. That's what
the velocity factor calculations were all about. Does the
0.66 velocity factor disappear when RG-8 is used as a stub?
Then neither does the 0.0175 coil velocity factor disappear
when it is used in a standing wave environment.

The cos(kz)*cos(wt) nature of the standing wave current
prohibits that standing wave current from being used to
determine the velocity factor of a coil or of a wire. The
lumped-circuit model assumes the velocity factor through
any and every coil to be *greater than unity*.
--
73, Cecil http://www.qsl.net/w5dxp