RSGB RadCom December 2007 Issue
 

"art" wrote in message news:3bd68052-1537-4b55-a745-
snip
Oh my, you sound so upset.
Your theory used in Eznec was designed
around known "reality" because you found the need to add the proviso
that there was a sino soidal current at all points on the radiator.
Number one, it is not legitamate to add a proviso or a special
condition
to a known law.( Electrical or Mechanical)
Number two It becomes a worse problem when the proviso added is in
error.
Number three, You should not retain a proviso if it proves incorrect .
The fact that present theory has passed the test of time means
nothing.
The threat of retaliation trumps science when humans are concerned.
Gallilao never saw the day that the earth was proven round which
stood the test for a very very long time.
But you could explain to the world how a sino soidal current passes
thru
a distributed capacitance and still retain its properties as it
encounters every segment. This is per the proviso you have placed
with
existing Maxwell's laws with respect to your computor program.
But no you can't! Until then I don't think you are equipped to say
that written theory can be taken as fact.Especially when known laws
are twisted so you can gyrate your program to known reality.
The old saying still stands, Garbage in will produce garbage out
unless the outputs are subject to reprocessing !

Art Unwin...KB9MZ

snip


Art,

I'm sure Roy is quite capable of defending himself against your accusations,
but I think you are being a trifle unfair. EZNEC is a simulation designed to
predict the performance of an antenna design. Being a simulation, certain
assumptions and approximations have to be made in order for it to work. The
fact is that in most situations it does provide an accurate prediction of
antenna performance. There are some special circumstances where it won't.

Integral calculus has been described as one of the greatest advances in
mathematical science, but that is still only an approximation method and
nobody complains about that.

Let's all behave and not argue okay?

Best wishes
Mike G0ULI

RSGB RadCom December 2007 Issue
 

On Thu, 15 Nov 2007 22:54:14 -0000, "Mike Kaliski"
wrote:

I guess you are skeptical that there might be a specific point on an antenna
that matches the impedence of free space and thus radiates energy more
strongly than the rest of the antenna.

Hi Mike,

When your energy is frequency based, and your interface is large in
terms of wavelength (and anything over 1/10th wave is still large);
then trying to home in on a "specific" point is not very specific at
all.

This is the subject that interests me
and I intend to try and establish to my own satisfaction whether this is or
is not the case.

You will probably be able to approach it by degrees, but as you get
closer focus has to be abandoned (classic wavelength vs. physical
length diffraction limitation).

If this can be established in a scientifically robust
manner, then I will present my experimental method, measurements and
conclusions for critical examination. I am unfamiliar with work that has
been carried out in this field, so I will carry out further searches and
reading before embarking on reinventing the wheel. Thanks for the link and
the suggestion about plasmonics and fields, I will follow up on that.

More towards the RF end of the scale, diffraction limits (being
broken) and your interest, consider:
http://physicsworld.com/cws/article/print/17398

You can listen to others crow about how "someday" science will catch
up, or you can simply see that science has already left that crowd in
the dust. The article above (and others found by googling "Boeing,
and "negative refractance") will give you an RF material that turns
beams in the opposite direction of what would be expected.

Our crowing buddies would shrug this off (lack of experience in this
matter) because they don't realize that it solves the diffraction
limitation. Build your own model and throw RF against it yourself to
discover a lens with absolute (not fuzzy) focus.

73's
Richard Clark, KB7QHC

RSGB RadCom December 2007 Issue
 

On 15 Nov, 18:25, "Mike Kaliski" wrote:
"art" wrote in message news:3bd68052-1537-4b55-a745-

snip





Oh my, you sound so upset.
Your theory used in Eznec was designed
around known "reality" because you found the need to add the proviso
that there was a sino soidal current at all points on the radiator.
Number one, it is not legitamate to add a proviso or a special
condition
to a known law.( Electrical or Mechanical)
Number two It becomes a worse problem when the proviso added is in
error.
Number three, You should not retain a proviso if it proves incorrect .
The fact that present theory has passed the test of time means
nothing.
The threat of retaliation trumps science when humans are concerned.
Gallilao never saw the day that the earth was proven round which
stood the test for a very very long time.
But you could explain to the world how a sino soidal current passes
thru
a distributed capacitance and still retain its properties as it
encounters every segment. This is per the proviso you have placed
with
existing Maxwell's laws with respect to your computor program.
But no you can't! Until then I don't think you are equipped to say
that written theory can be taken as fact.Especially when known laws
are twisted so you can gyrate your program to known reality.
The old saying still stands, Garbage in will produce garbage out
unless the outputs are subject to reprocessing !

Art Unwin...KB9MZ

snip

Art,

I'm sure Roy is quite capable of defending himself against your accusations,
but I think you are being a trifle unfair. EZNEC is a simulation designed to
predict the performance of an antenna design. Being a simulation, certain
assumptions and approximations have to be made in order for it to work. The
fact is that in most situations it does provide an accurate prediction of
antenna performance. There are some special circumstances where it won't.

Integral calculus has been described as one of the greatest advances in
mathematical science, but that is still only an approximation method and
nobody complains about that.

Let's all behave and not argue okay?

Best wishes
Mike G0ULI- Hide quoted text -

- Show quoted text -

But I am behaving. I am sure that both Roy and others who deal with
NEC4
will admit that they have played with the truth with respect to
antenna programs.
I would venture to say that computor programs are good at what they do
but
it is for all the wrong reasons. Maxwell's laws are just that..Laws.
It is mathematically fraudulent to add anything to those laws under
the banner of Maxwell.
When Roy left the ARRL circle he challenged antena companies to verify
their claims
with respect to gain. By the same token I am challenging to prove the
veracity
of the additional statement that a sino soidal current is present at
every segment point.
Not is it only mathematically illegal to modify a law the addition
also defies all electrical laws.
A radiator has distributed capacitance and I am not aware that a
capacitor will
allow the passage of a time varying current, this is what the
programing states.
He ofcourse can justify why he did this to the satisfaction of all but
he cannot justify
the insertion of such.
Now my antenna operates quite nicely following another aproachyet Roy
vehamently
derides this new aproach when he himself cannot verify his own
actions.
Fairness can be seen in different ways. He can be belligerent in
analysing my aproach
yet at the same time defend an action that he cannot prove to be true.
A person always has the right to defend himself especially against
those
who are mentally challenged. When he provides how distributed
capacitance does not affect
the time varient that Maxwell states is a titular point of his laws I
will readily
retract that remark. Until that time I will defend the veracity of my
aproach which
succesfully produces antennas and arrays in a smaller volume that
present theory
predicts as impossible. As an adder, I am discussing antennas and not
"systems" as Roy
would imply.
Nothing personal, Like Reagan I like verification since trust
does not prove to be enough and I will always defend if I am attacked.
Best regards
Cheers with a Black and Tan
Art Unwin.....KB9MZ...xg

RSGB RadCom December 2007 Issue
 

Mike Kaliski wrote:

...
I'm sure Roy is quite capable of defending himself against your
accusations, but I think you are being a trifle unfair. EZNEC is a
simulation designed to predict the performance of an antenna design.
...
Best wishes
Mike G0ULI

No need for any defense; EZNEC (and other apps) are the "state of the
art" as far as hams are concerned--they are more than adequate for our
needs. Too bad so many view this/these discussions as an "attack."

These "arguments" are only an attempt to peer over the horizon on
possible new discoveries and inner workings of antennas.

Nothing in my posts are meant to be an attack on EZNEC, Roy, or for that
matter, any others and those who use them to construct and place into
service the antennas in common use and which perform well. I am sure
most others are of a like mind.

Arts' feathers have just been ruffled ... something we all have been
guilty of--at one time or another.

Regards,
JS

RSGB RadCom December 2007 Issue
 

On 15 Nov, 19:08, John Smith wrote:
Mike Kaliski wrote:

...

I'm sure Roy is quite capable of defending himself against your
accusations, but I think you are being a trifle unfair. EZNEC is a
simulation designed to predict the performance of an antenna design.
...
Best wishes
Mike G0ULI

No need for any defense; EZNEC (and other apps) are the "state of the
art" as far as hams are concerned--they are more than adequate for our
needs. Too bad so many view this/these discussions as an "attack."

These "arguments" are only an attempt to peer over the horizon on
possible new discoveries and inner workings of antennas.

Nothing in my posts are meant to be an attack on EZNEC, Roy, or for that
matter, any others and those who use them to construct and place into
service the antennas in common use and which perform well. I am sure
most others are of a like mind.

Arts' feathers have just been ruffled ... something we all have been
guilty of--at one time or another.

Regards,
JS

Just to clear things. I am not saying that Roy's work does not predict
with good accuracy how certain antennas perform. What I am saying
it is that it does this despite manipulations for the wrong reasons.
Isn't that sort of thing what makes us different to E ham.
One can hold his own theories but not by attempting to deride those
whose
theories differs. There must be room for differences in thought amoung
reasonable men or advancement in science is squashed and adherence
to written theories could last for ever. A moderator can ensure that
present theories remain sacrosant if that is what members desires!
Art

RSGB RadCom December 2007 Issue
 

art wrote:

...
Just to clear things. I am not saying that Roy's work does not predict
with good accuracy how certain antennas perform. What I am saying
it is that it does this despite manipulations for the wrong reasons.
Isn't that sort of thing what makes us different to E ham.
One can hold his own theories but not by attempting to deride those
whose
theories differs. There must be room for differences in thought amoung
reasonable men or advancement in science is squashed and adherence
to written theories could last for ever. A moderator can ensure that
present theories remain sacrosant if that is what members desires!
Art

Yer preachin' to the choir.

There is more than enough to "prove" there are errors/holes in our
present knowledge--well, IMHO, at least. No one is suggesting we just
"throw it all away" ... I don't think I am alone--some just remain
silent to escape the stones and arrows.

I have many more questions than answers, but don't we all? Be
interesting in coming back in a hundred years and viewing "em
radiation"/antenna theory at that time.

You just don't take well to bein' "poked with a stick!" ;-)

Regards,
JS

RSGB RadCom December 2007 Issue
 

On Thu, 15 Nov 2007 23:35:08 -0500, "Stefan Wolfe"
wrote:


"Richard Clark" wrote in message
.. .
On Thu, 15 Nov 2007 12:29:08 -0000, "Mike Kaliski"
wrote:

http://home.comcast.net/~kb7qhc/ante...pole/index.htm

I don't intend to go too far off topic but the near field results are so
strikingly different when you add the ground screen. This is an area that I
am not so familiar with

The old saw of dipoles not needing a ground (one of those things that
makes them so much "better" than verticals) is confounded because they
do need a ground - if you want more gain. I don't suppose this is
covered in the RSGB RadCom issue (and now we are back on topic).

It would seem that the strictly horizontal dipole crowd doesn't need
the gain....

The simple fact is that a ground screen reduces ground loss.

. At 80M does the program assume that the ground at
near field is basically a dielectric instead of a conductor, acting like a
large capacitor

Basically, more like a resistor. No new science is being marketed
here.

whereas the screen is a pure conductor?

Basically, more like a screen (as in shield). If you want to keep it
in the metaphor of "large capacitors" that is what near fields are
for. Remove the screen and you have a lossy capacitor. A large
inductor could as easily demand center stage and without the screen,
we are talking about a lossy inductor.

It would seem this
would have to be related to the explanation, correct? It sure shows at least
one possible advantage of using a lot of radials; it reduces near field (?)

Reduces loss. Near fields being reduced is something of an oxymoron.
They are still as near as they ever were, the page(s) only illustrate
the impedance of near space, expressed in terms of a ratio we commonly
call mismatch. In other words, the conventional 377 Ohms of
air/vacuum, in the proximity of a conductor, is quite different in
value. In some regions, it is represented as being as low as 120
Ohms, in other regions as high as 1200 Ohms. As both these values
represent a mismatch ratio of the order of 3:1 (or, contrariwise 1:3),
the colors are mapping only the ratios, not the 10-fold variation
(that would be too many colors). With finer grain resolution, these
values plunge and rise well beyond these arbitrarily restricted
values.

Someone is sure to exclaim this would only increase NVIS. Yes, the
skyward lobe is enhanced, but so is the lobe out to the horizon. A
reflector would contribute to the first gain, less loss accounts for
both gains.

I also analyze verticals and exotic designs (aka fractals) which have
mappings that look like tropical storms.

73's
Richard Clark, KB7QHC

RSGB RadCom December 2007 Issue
 

Art wrote:
"By the same token I am challenging to prove the veracity of the
statement that a sino soidal current is present at every segment point."

An antenna is generally a linear passive device meaning that a
sinusoidal wave entering an antenna produces sinusoidal fields which
induce sinusoidal voltages and currents in the distant receiving
antenna.

Sinusoidal voltages appear at every point on such an antenna and
sinusoidal currents pass over the surface of every point of the antenna.
Insulators of course interrupt conduction currents and allow the rise of
voltage gradients.

Induced currents are produced by the electric field of the wave in the
insulation of free space by the displacement (capacitive action) current
of an antenna. Maxwell speculated that displacement generated a magnetic
field same as conduction did, and that was the secret of radiation. He
was proved correct. A magnetic field generated an electric field and an
electric field generated a magnetic field so that the two fields locked
and traveling together go on ond on forever.

Most antennas have two waves traveling in opposite directions, an
incident wave and a reflected wave. Both pass through every point on the
antenna conductor.

A directional coupler can access the wave traveling in one direction
while ignoring the wave traveling in the opposite direction.

Large variations in voltage appearing on the antenna make the familiar
standing wave pattern but this is not a true picture of the individual
waves making up the combined wave. The effective values of the incident
and reflected waves decline steadily but gradually along the antenna as
they travel in opposite directions.

A sinusoidal current is present at every segment point and only slowly
changes from point to point. Two sine waves of the same frequency always
combine at a point to create another sine wave of the same frequency.

Best regards, Richard Harrison, KB5WZI

RSGB RadCom December 2007 Issue
 

Richard Harrison wrote:

A magnetic field generated an electric field and an
electric field generated a magnetic field so that the two fields locked
and traveling together go on ond on forever.
...
Best regards, Richard Harrison, KB5WZI


From the above, are the two in a constant state of interaction? The
magnetic reversing to electric--the electric reversing to magnetic?

Or, is their relationship static to one another?

Regards,
JS

RSGB RadCom December 2007 Issue
 

"Richard Clark" wrote in message
...
On Thu, 15 Nov 2007 22:54:14 -0000, "Mike Kaliski"
wrote:

I guess you are skeptical that there might be a specific point on an
antenna
that matches the impedence of free space and thus radiates energy more
strongly than the rest of the antenna.

Hi Mike,

When your energy is frequency based, and your interface is large in
terms of wavelength (and anything over 1/10th wave is still large);
then trying to home in on a "specific" point is not very specific at
all.

This is the subject that interests me
and I intend to try and establish to my own satisfaction whether this is
or
is not the case.

You will probably be able to approach it by degrees, but as you get
closer focus has to be abandoned (classic wavelength vs. physical
length diffraction limitation).

If this can be established in a scientifically robust
manner, then I will present my experimental method, measurements and
conclusions for critical examination. I am unfamiliar with work that has
been carried out in this field, so I will carry out further searches and
reading before embarking on reinventing the wheel. Thanks for the link and
the suggestion about plasmonics and fields, I will follow up on that.

More towards the RF end of the scale, diffraction limits (being
broken) and your interest, consider:
http://physicsworld.com/cws/article/print/17398

You can listen to others crow about how "someday" science will catch
up, or you can simply see that science has already left that crowd in
the dust. The article above (and others found by googling "Boeing,
and "negative refractance") will give you an RF material that turns
beams in the opposite direction of what would be expected.

Our crowing buddies would shrug this off (lack of experience in this
matter) because they don't realize that it solves the diffraction
limitation. Build your own model and throw RF against it yourself to
discover a lens with absolute (not fuzzy) focus.

73's
Richard Clark, KB7QHC

Thank you Richard. I was aware of negative index refraction materials. Now
to make them sufficiently broadband and work at optical frequencies...

Cheers
Mike G0ULI

RSGB RadCom December 2007 Issue
 

"Stefan Wolfe" wrote in message
...

"Mike Kaliski" wrote in message
...

Integral calculus has been described as one of the greatest advances in
mathematical science, but that is still only an approximation method and
nobody complains about that.

Mike, it is hard for me to let this go (but it is off topic). Integral
calculus is not an approximation, it is exact. The prior art, the
summation method of adding the areas of small rectangles, was the
approximation. The genius of integral calculus was that it was able to sum
an infinite number of infinitely small rectangles and come up with an
exact answer. For the answer to be exact, it was necessary to deal with
infinity (undefined) and the concept actually works. It even works in many
cases where there is an asymptote that is infinitely long (f(x) =
1/x**2)).
END OF COMMENT (no, I will not offer experimental proof that integral
calculus is exact :-))
Stefan

All true and it works very well. It's just that being forced into accepting
such concepts as infinity and the square root of minus one without being
able to pin down exactly what they are shows up how limited we are in our
abilities to deal with the true nature of the universe. How can anyone
really get to grips with such concepts as an infinity of infinities?

Mike G0ULI

RSGB RadCom December 2007 Issue
 

art wrote:
By the same token I am challenging to prove the
veracity of the additional statement that a sino
soidal current is present at every segment point.

If one threads a toroidal transformer over
a dipole wire, one will observe a sinusoidal
waveform (if the source is sinusoidal).
--
73, Cecil http://www.w5dxp.com

RSGB RadCom December 2007 Issue
 

Stefan Wolfe wrote:
"Tom Donaly" wrote:
Have you verified this experimentally, Cecil? If you did,
how did you do it?

This work has already been done.

Thanks Stefan, Tom apparently believes I should
reinvent the wheel every time I ride my Harley. :-)
--
73, Cecil http://www.w5dxp.com

RSGB RadCom December 2007 Issue
 

Richard Clark wrote:
The old saw of dipoles not needing a ground (one of those things that
makes them so much "better" than verticals) is confounded because they
do need a ground - if you want more gain.

What's the difference in free space gain between a
vertical dipole and a horizontal dipole? :-)
--
73, Cecil http://www.w5dxp.com

RSGB RadCom December 2007 Issue
 

On Nov 15, 2:41 pm, Cecil Moore wrote:

Reflections occur only at physical impedance
discontinuities.

Richard Feynman said there is a probability that reflection will occur
at any point within a partially reflecting media. He explained that
all the probabilities (including phase) sum in order to generate the
net, observed effect. Your observation about the full-wave loop is
probably a good example.

73, ac6xg

RSGB RadCom December 2007 Issue
 

John Smith wrote:
"From the above, are the two in a constant state of interaction?"

On page 1 of Terman`s "Electronic and Radio Engineering":
"These waves, which are commonly called radio waves, travel with the
velocity of light and consist of magnetic and electric fields that are
at right angles to each other and are at right angles to the direction
of travel. If these electric and magnetic fields could actually be seen,
the wave would have the appearance indicated in Fig. 1-1."

Maxwell`s first field equation says that a changing magnetic field will
produce an electric field. The second equation says that a changing
electric field will produce a magnetic field.

The alternating magnetic field creates an alternating electric field in
the space surrounding it. Due to the alternation of the electric field
an alternating displacement current will exist in space, which will give
rise to another alternating magnetic field in the space surrounding the
displacement current, etc., etc., etc..

Maxwell`s proof is courtesy B. Whitfield Griffirh, Jr.`s
"Radio-Electronic Transmission Fundamentals", now in reprint by Scitech
Publidhing, Inc..

Best regards, Richard Harrison, KB5WZI

RSGB RadCom December 2007 Issue
 

Richard Harrison wrote:

...
The alternating magnetic field creates an alternating electric field in
the space surrounding it. Due to the alternation of the electric field
an alternating displacement current will exist in space, which will give
rise to another alternating magnetic field in the space surrounding the
displacement current, etc., etc., etc..

Maxwell`s proof is courtesy B. Whitfield Griffirh, Jr.`s
"Radio-Electronic Transmission Fundamentals", now in reprint by Scitech
Publidhing, Inc..

Best regards, Richard Harrison, KB5WZI


Richard;

Thanks for taking the time to post that data.

Of course, in my "addled way of thinking", I still see the probability
of a media in which these actions are taking place (electric to magnetic
and magnetic to electric )--such as when you swing a wire (media)
through a magnetic field.

But, really, it is all still a question ... anyway, pondering keeps me
outta the bars. :-)

Regards,
JS

RSGB RadCom December 2007 Issue
 

Jim Kelley wrote:
Richard Feynman said there is a probability that reflection will occur
at any point within a partially reflecting media.

Of course, there are always 2nd, 3rd, ... Nth order effects.
On this newsgroup, we are usually talking about first order
effects. I had a recent email exchange with someone talking
about the part of the ground wave that escapes absorption
because of the earth's curvature and is probably ignored
by NEC simulators but not by AM broadcasters.
--
73, Cecil http://www.w5dxp.com

RSGB RadCom December 2007 Issue
 

Richard Harrison wrote:
Maxwell`s first field equation says that a changing magnetic field will
produce an electric field. The second equation says that a changing
electric field will produce a magnetic field.

Does this cause and effect chain of events result in a
phase lag between the electric and magnetic fields?
--
73, Cecil http://www.w5dxp.com

RSGB RadCom December 2007 Issue
 

On 16 Nov, 10:38, Cecil Moore wrote:
Richard Harrison wrote:
Maxwell`s first field equation says that a changing magnetic field will
produce an electric field. The second equation says that a changing
electric field will produce a magnetic field.

Does this cause and effect chain of events result in a
phase lag between the electric and magnetic fields?
--
73, Cecil http://www.w5dxp.com

I would like more than that!
I would like to know what Terman had to say about radiation
which is a cause of most discussion the summation of which
is not accepted by the IEEE. I don't think he has given any
credit to Maxwell, Faraday, Heaviside or any of the pioneers
in any of his books so it would be interesting to know why
his wrestling with the mechanics of radiation was to no availe!.
And Richard, when you have finished reading from Terman
to get us to sleep, would you consider for your next book
to read to us, like Lady Chatterlies Lover by D.H. Lawrence?
That book may well prevent you going to sleep as well while
reading on the net Most of us have read all the volumes by
Terman so a different reading book may well be of more interest.
Art

RSGB RadCom December 2007 Issue
 

art wrote:

...
And Richard, when you have finished reading from Terman
to get us to sleep, would you consider for your next book
to read to us, like Lady Chatterlies Lover by D.H. Lawrence?
That book may well prevent you going to sleep as well while
reading on the net Most of us have read all the volumes by
Terman so a different reading book may well be of more interest.
Art

Art;

This text wastes time/space/patience.

You fault others for such petty "stick poking" as the above. Are you
sure you wouldn't rather keep this to a minimum?

Regards,
JS

RSGB RadCom December 2007 Issue
 

Cecil, W5DXP wrote:
"Does this cause and effect chain of events result in aphase lag between
electric and magnetic fields?"

Never saw a phase lag suggested. As radiation impedance is a resistance
even in free space, I expect rise and fall in electric and magnetic
fields is simultaneous even as they speed away at the velocity of light.
Which came first, the electric or the magnetic?

Best regards, Richard Harrison, KB5WZI

RSGB RadCom December 2007 Issue
 

Cecil Moore wrote:

Jim Kelley wrote:

Richard Feynman said there is a probability that reflection will occur
at any point within a partially reflecting media.


Of course, there are always 2nd, 3rd, ... Nth order effects.
On this newsgroup, we are usually talking about first order
effects.

And so was Dr. Feynman. You really ought to freshen up on your QED. ;-)

73, ac6xg

RSGB RadCom December 2007 Issue
 

Richard Harrison wrote:
Never saw a phase lag suggested. As radiation impedance is a resistance
even in free space, I expect rise and fall in electric and magnetic
fields is simultaneous even as they speed away at the velocity of light.
Which came first, the electric or the magnetic?

Does "simultaneous" imply faster than light? :-)
(Photons don't have the phase lag problem).
--
73, Cecil http://www.w5dxp.com

RSGB RadCom December 2007 Issue
 

Jim Kelley wrote:

Cecil Moore wrote:
Of course, there are always 2nd, 3rd, ... Nth order effects.
On this newsgroup, we are usually talking about first order
effects.

And so was Dr. Feynman.

I seriously doubt that Dr. Feynman ever said that the
majority of reflections occur somewhere else besides
the junction of two mediums.
--
73, Cecil http://www.w5dxp.com

RSGB RadCom December 2007 Issue
 

Richard Harrison wrote:
Cecil, W5DXP wrote:
"Does this cause and effect chain of events result in aphase lag between
electric and magnetic fields?"

Never saw a phase lag suggested. As radiation impedance is a resistance
even in free space, I expect rise and fall in electric and magnetic
fields is simultaneous even as they speed away at the velocity of light.
Which came first, the electric or the magnetic?

The ratio of E to H fields of a wave is known as the wave impedance. It
has both a magnitude and a phase angle (or real and imaginary
components). The impedance of a plane wave propagating through a medium
is the intrinsic impedance of the medium. For example, the ratio of E to
H of a plane wave propagating through space equals the intrinsic
impedance of space. The intrinsic impedance of space is purely real
(~377 + j0 ohms), which tells you that the ratio of E to H of a plane
wave propagating through it is purely real. This means there is no phase
difference between the two - E and H are in phase.

But the intrinsic impedance of many materials (e.g., dirt) isn't purely
real, so there is a non-zero phase angle between E and H fields of plane
waves propagating through them.

The ratio of E to H is also often complex in the near field around an
antenna, and usually with a magnitude other than 377 ohms. So in that
region, there's also a phase difference between E and H.

Roy Lewallen, W7EL

RSGB RadCom December 2007 Issue
 

Roy Lewallen wrote:
For example, the ratio of E to
H of a plane wave propagating through space equals the intrinsic
impedance of space. The intrinsic impedance of space is purely real
(~377 + j0 ohms), which tells you that the ratio of E to H of a plane
wave propagating through it is purely real. This means there is no phase
difference between the two - E and H are in phase.

But if the E-field causes the H-field which in turn causes
the E-field, how is a delay avoided? Isn't that faster than
light generation of fields?
--
73, Cecil http://www.w5dxp.com