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Jim Kelley wrote:
Cecil Moore wrote:
Kraus, in his book entitled "Antennas" ignores almost nothing about
antennas.

On the contrary, when Kraus talks about standing-wave
antenna current, he ignores everything except standing
waves. Here are some quotes:

"Antennas ...", by Kraus, 3rd edition:
Standing Wave Antennas

Page 187: "A sinusoidal current distribution may be
regarded as the standing wave produced by two uniform
(unattenuated) traveling waves of equal amplitude moving
in opposite directions along the antenna."

Page 464: "It is generally assumed that the current
distribution of a thin-wire antenna is sinusoidal, and
that the phase is constant over a 1/2WL interval, ..."

Both of those statements assume nothing but standing wave
current on a standing wave antenna. Have you looked at
that graph of standing wave current amplitude and phase
that Kraus provides in "Antennas"?

Kraus normalizes the feedpoint current to 1.0 and that's
good enough for me.

Yes, unless of course you're talking about a real antenna with actual
current on it. That is what I thought we were talking about. My
recollection is that it was resonant on 75 meters, and the coil and
stinger have very specific dimensions.

Unfortunately, the simulation of a 75m Bugcatcher loading
coil violates the EZNEC segmentation rules on 4 MHz. To
avoid objections to such, I have used the 75m Bugcatcher
loading coil form factor on a loaded 40m mobile antenna
using about 14 turns. EZNEC doesn't complain about that
6" diameter, 4 tpi form factor used on 40m. That 40m
mobile antenna file can be downloaded from:

http://www.w5dxp.com/coil426.EZ

The current at the bottom of the coil is
1.0168 amps at 0.00 degrees

The current at the top of the coil is
..8179 amps at -0.06 degrees

In this case, the delay through the coil is unrelated
to the phase shift.

The actual value of Imax obviously depends
upon the power incident upon the antenna. If one assumes a
current of 1.0 at the feedpoint of the coil, then one can calculate
the Imax at the base of the stinger given the Z0 of the loading
coil and the Z0 of the stinger.

It might even be better to measure it - with some type of current probe
device. Then you could solve for phase at any x or t you want.

Roy already made the necessary measurements. All he needs
is help in comprehending the results. Unfortunately, he is
still suffering from the misconception that the current
phase that he "measured" is associated with the propagation
delay through the loading when it is not.

The phase of the current in a standing wave antenna
changes hardly at all through a wire or through a loading
coil. Running the above file under EZNEC proves that
statement. Roy has even, in the past, agreed with the
EZNEC results yet he continues to ignore the nature of
the current on a standing wave antenna as reported by
EZNEC. Go figure.

As Gene Fuller asserted years ago, the phase information
in the current on a standing-wave antenna is buried in
the current magnitude measurement, not in the current
phase measurement. You seem to agree.

But Roy did NOT use the magnitude measurement to calculate
the phase shift!!! I explained how to take the ARCCOSine
of the current normalized magnitude to calculate the actual
phase shift through a wire more than 5 years ago. He called
the concept gobbledygook, plonked me, threatened to refund
my EZNEC purchase price, and revoke my customer support.

An EZNEC simulation using the *SAME* 40m loading coil above
using traveling wave current, showing an actual phase shift
of ~40 degrees is at:

http://www.w5dxp.com/coil426s.EZ

The current at the bottom of the coil is
1.0053 amps at -3.25 degrees.

The current at the top of the the coil is
..90356 amps at -43.43 degrees.

In this case, the delay through the coil is proportional
to the phase shift.

Hopefully, you or someone else who understands what I am
saying will contact Roy about his conceptual blunders.
He keeps trying to avoid the discussion of large bugcatcher
loading coils by retreating to the shelter of a small
toroidal coil which more closely matches the lumped-circuit
model along with his mistaken concepts. Unfortunately, his
small toroidal coil bears no resemblance to a 75m Texas
Bugcatcher coil which is the subject of the discussion.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

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Cecil Moore wrote:
Hopefully, you or someone else who understands what I am
saying will contact Roy about his conceptual blunders.

On w8ji's web page: http://www.w8ji.com/agreeing_measurements.htm

Roy Lewallen wrote:
As described in my posting on rraa of November 11,
the inductor "replaces" about 33 electrical degrees
of the antenna.

If "the inductor replaces about 33 electrical degrees
of the antenna", isn't the argument over?
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

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On May 2, 9:52*am, Cecil Moore wrote:
Cecil Moore wrote:
Hopefully, you or someone else who understands what I am
saying will contact Roy about his conceptual blunders.

On w8ji's web page:http://www.w8ji.com/agreeing_measurements.htm

Roy Lewallen wrote:
As described in my posting on rraa of November 11,
the inductor "replaces" about 33 electrical degrees
of the antenna.

If "the inductor replaces about 33 electrical degrees
of the antenna", isn't the argument over?
--
73, Cecil, IEEE, OOTC, *http://www.w5dxp.com

Now , now, Cecil. you cannot equate a coil with electrical degrees of
an antenna.
Lumped loads are not included in the laws of Maxwell only distributed
loads
Art

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Art Unwin wrote:
Lumped loads are not included in the laws of Maxwell only distributed
loads

A 75m Texas Bugcatcher loading coil certainly
qualifies as a distributed load being about
1/8WL long.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

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On May 3, 9:41*am, Cecil Moore wrote:
Art Unwin wrote:
Lumped loads are not included in the laws of Maxwell only distributed
loads

A 75m Texas Bugcatcher loading coil certainly
qualifies as a distributed load being about
1/8WL long.
--
73, Cecil, IEEE, OOTC, *http://www.w5dxp.com

Aw come on Cecil
It is a lumped load which is unbalanced and Maxwell demands
equilibrium ie balanced. Yes, it has distributed loading but formed
into a helix antenna
such that it includes lumped loading. Maxwell in his search for
maximum efficiency he would have added a symbol to his equations for
lumped loads . He then would have to include pitch and the like but he
just did not consider it as a consideration.
This is clearly shown with a WL verticle when for maximum effeiciency
it is tipped from right angles to the Earth ala the Corriolis effect
with which you are tampering with
when current rotates, and its introduction of a slow wave and a
different velocity factor
This is why you cannot equate lumped loads with antenna degrees, only
approximate
I have no which to debate it so I will leave it at that. Soon I will
be heading home.
No offense intended but physics is physics
Art

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"Art Unwin" wrote in message
...
Maxwell in his search for
maximum efficiency he would have added a symbol to his equations for
lumped loads .

lumped loads like capacitors and inductors are indeed included in maxwell's
equations, its just a matter of scale. the problem is that most modeling
programs can't handle the large scale variation needed to go from a large
radiator down to a small coil and still maintain the segments properly. but
indeed the fields from and within the lumped elements do follow maxwell's
equations.

This is clearly shown with a WL verticle when for maximum effeiciency
it is tipped from right angles to the Earth ala the Corriolis effect

art is a bit tipped from vertical also, but i doubt if it is a corriolis
problem.

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Aw come on Cecil
It is a lumped load which is unbalanced and Maxwell demands
equilibrium ie balanced. Yes, it has distributed loading but formed
into a helix antenna
such that it includes lumped loading. Maxwell in his search for
maximum efficiency he would have added a symbol to his equations for
lumped loads . He then would have to include pitch and the like but he
just did not consider it as a consideration.
This is clearly shown with a WL verticle when for maximum effeiciency
it is tipped from right angles to the Earth ala the Corriolis effect
with which you are tampering with
when current rotates, and its introduction of a slow wave and a
different velocity factor
This is why you cannot equate lumped loads with antenna degrees, only
approximate
I have no which to debate it so I will leave it at that. Soon I will
be heading home.
No offense intended but physics is physics
Art

Hi Art,
Can you reference a professional journal that confirms this Coriolis (I
believe that is the correct spelling) effect w/ respect to tipped
verticals - or is this something only you have discovered?

Dale W4OP

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Dave wrote:

lumped loads like capacitors and inductors are indeed included in
maxwell's equations, its just a matter of scale. the problem is that
most modeling programs can't handle the large scale variation needed to
go from a large radiator down to a small coil and still maintain the
segments properly. . .

I don't quite understand this. Could you elaborate please?

Roy Lewallen, W7EL

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"Dale Parfitt" wrote in message
...
Hi Art,
Can you reference a professional journal that confirms this Coriolis (I
believe that is the correct spelling) effect w/ respect to tipped
verticals - or is this something only you have discovered?

thats one of art's discoveries. though it started out as being because of
the weak force instead of the coriolis effect, i think coriolis is probably
more believable... but do you have to tip them different in the north vs
south hemispheres? and what happens at the poles and equator, are they
straight up or horizontal??

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On May 3, 2:15*pm, "Dale Parfitt" wrote:
*Aw come on Cecil
It is a lumped load which is unbalanced and Maxwell demands
equilibrium ie balanced. Yes, it has distributed loading but formed
into a helix antenna
such that it includes lumped loading. *Maxwell in his search for
maximum efficiency he would have added a symbol to his equations for
lumped loads . He then would have to include pitch and the like but he
just did not consider it as a consideration.
This is clearly shown with a WL verticle when for maximum effeiciency
it is tipped from right angles to the Earth ala the Corriolis effect
with which you are tampering with
when current rotates, and its introduction of a slow wave and a
different velocity factor
This is why you cannot equate lumped loads with antenna degrees, only
approximate
I have no which to debate it so I will leave it at that. Soon I will
be heading home.
No offense intended but physics is physics
Art

Hi Art,
Can you reference a professional journal that confirms this Coriolis (I
believe that is the correct spelling) effect w/ respect to tipped
verticals - or is this something only you have discovered?

Dale W4OP

Coriolis effect is already well accepted in science.
A tipped radiator comes about when one uses optimizer style programs
based on the teaching or equations of Maxwell which accounts for ALL
forces involved within an arbitrary border ie equilibrium per the
teachings of Newton. Most people ignore the tipping arrangement for
simplicity and use programs strictly for planar forms which is an good
approximation in accounting for all generated radiation