Antenna reception theory
 

Gene, W4SZ write:
"As has been said many times on this newsgroup, it is not possible to
filter out one field component or the other."

Saying it does not make it so.

Countless Faraday screens are at work removing the E-field component
from electromagnetic waves. Faraday said that the voltage in a coupled
circuit depends only on the rate of change of the magnetic flux through
the circuit. He was refering to induced voltage. It was 1831 when
Michael Faraday observed the interaction between primary and secondary
coils in what was likely the world`s first transformer. Faraday made it
himself and noted that the needle of a galvanometer connected across one
coil deflected briefly whenever he connected or disconnected a battery
across the other coil.

Antenna reception theory
 

it is just as easy to remove the H-field from the wave as it is to
remove the E-field with a Faraday screen.

To remove the H-field, one sure way is to completely enclose two coils
so they are completely shielded from each other and all electromagnetic
waves. Put the coils in separate metal cans. Put a tiny hole in each
can. Conect one termial of each coil to its end of a coupling capcitor.
Ground the other terminal of each coil.. Ground is the return path for
the coils but it must run on the surfaces of the cans and through the
tiny holes due to skin effect.
Complete shielding removes the H-field as a coupling agent. Only E-field
coupling is provided via the coupling capacitor.

Best regards, Richard Harrison, KB5WZI

Antenna reception theory
 

Cecil Moore wrote:

Jim Kelley wrote:

Wave P1 contains 75 watts and Wave P2 contains 8.33 watts.
Without a source of constructive interference energy, they cannot
add up to 133.33 watts.


And obviously he still doesn't believe it, Gene.

I should have said Tom. If I were Cecil I'd have blamed the error on my
glasses or my advanced age. ;-)

You don't really support superposition of
powers and violations of conservation of energy, do you?.

Depending on how high you keep your squelch set, you should already
pretty well know what I think about those things.

You're at least partially right though. Power does not superpose
(because, for among other reasons, it doesn't move or propagate). The
point you continue to miss is that power does not interfere either. Nor
is it valid to take the square root of the product of two power numbers
and claim that it turns around miraculously and goes the other
direction. But that's what you've miguidedly presented to the readers
of World Radio as fact. The irradiance equations are nevertheless
correct because power goes as the square of the fields - which do of
course superpose and interfere. The equations accurately describe the
effect - the end result, the outcome, not necessarily the cause or the
mechanism by which the result is achieved.

Before we go any further (and it is my sincerest hope that we do not), I
agree with Melles-Griot, Born and Wolf, Hecht, Jackson, and the other
E&M and optics books. What I disagree with (and I'm sure given the
opportunity so would the above mentioned authors) is some of your
interpretation of the physical phenomenon they describe.

73, ac6xg

Antenna reception theory
 

Gene Fuller wrote:
Yes, most people with
rudimentary arithmetic skills would agree that 75 plus 8.33 does not
equal 133.33.

Too bad Dr. Best posted the equation: "Ptotal = 75w + 8.33w = 133.33w"
on this newsgroup (and, thank goodness, left it out of his article) so
he obviously disagreed with you at the time. He also said that interference
had nothing to do with it.

However, anyone even remotely familiar with waves would readily
understand that the component waves Cecil loves to talk about are merely
mathematical conveniences. It is entire possible to set up other model
configurations, such as a combination of a one traveling wave and one
standing wave.

What happens at an impedance discontinuity given those circumstances? To
find out, read my WorldRadio article, Part I of which is posted on my web
page. Part II will be posted after Christmas. At the risk of raising your
politically incorrect ire as I have done with this technical posting,
MERRY CHRISTMAS!.

In order to make his model work, Cecil needs to invoke the mythical P3
and P4 on the source side of the reflection discontinuity. He never gets
around to explaining how these two waves, which exactly cancel at all
points in space and at all times, can contain any energy at all.

The answer is simple. Do waves contain any energy at all? Do waves that
cancel contain any energy? If waves contain no energy, they cannot exist,
and therefore are incapable of canceling. If they exist and cancel, they
contained energy just before their cancellation. Any way you cut it,
my approach is consistent with the laws of physics as enumerated in "Optics",
by Hecht, and yours leads to a contradiction of those laws of physics.

The reason that most practitioners of wave models solve for the fields
first and then worry about power or energy is:

a - This procedure works correctly all the time.

Yes, it does. But optics engineers didn't have the luxury of dealing
with voltages and currents. They had to solve the problem using powers.
And they did exactly that decades ago. That RF engineers refuse to
consider the laws of physics concerning EM waves developed by optics
engineers is absolutely astounding to me. W7EL put it best, something
to the effect that if it wasn't invented here, we don't want to hear it
(even if it is right). But I daresay that Eugene Hecht knows much more
about EM waves that you will ever know, given your closed mind.

I do not expect to change Cecil's mind. Other than his own potential
embarrassment from the silly publications in World Radio, his folly is
harmless.

You are just displaying your extreme ignorance, Gene. My "WorldRadio" article
corrects some of the *conceptual* errors in Dr. Best's QEX article but otherwise
contains the same equations as his article. If you disagree with me, you are
also disagreeing with Dr. Best's equations, i.e. you are between a rock and a
hard place.

It is interesting that the very people who tell us not to worry about energy
are the people who get so emotionally rabid when someone chooses to worry about
energy like real-world physicists do. What do they possibly have to lose besides
face, self-esteem, sleep, and their pseudo-religious guru status? :-)
--
73, Cecil http://www.qsl.net/w5dxp

Antenna reception theory
 

Jim Kelley wrote:
I should have said Tom. If I were Cecil I'd have blamed the error on my
glasses or my advanced age. ;-)

Alzheimer's can certainly strike at your age, Jim. :-) My Dad was
legally blind when he was my age so I'm ahead of the curve.

You're at least partially right though. Power does not superpose
(because, for among other reasons, it doesn't move or propagate). The
point you continue to miss is that power does not interfere either.

Here's a quote from my magazine article, Jim. If you would just cease
and desist from your MF'ing ways (that's "mind", not "muther"), you
might understand. Quote:
************************************************** ********************
"The words 'power flow' have been avoided even though
that is a term of common usage. For the purposes of this paper, energy
flows and power is a measure of that energy flowing at a fixed point or
plane. Likewise, the EM fields in the waves do the interfering. Powers,
treaded as scalars, are incapable of interference."
************************************************** ********************
But you already knew that's what I believe since I have been telling
you exactly that in CAPITAL LETTERS for years now and even sent you
an advance copy of my magazine article. I have never asserted the things
you claim that I have. Hopefully, the readers will recognize you for
what you are.

The irradiance equations are nevertheless
correct because power goes as the square of the fields - which do of
course superpose and interfere. The equations accurately describe the
effect - the end result, the outcome, not necessarily the cause or the
mechanism by which the result is achieved.

Where does the constructive interference energy come from, Jim? Hecht
says that in the absence of energy from other sources, the constructive
interference energy must be exactly matched by an equal amount of
destructive interference. Please present your credentials that allows
you to disagree with Eugene Hecht?

Before we go any further (and it is my sincerest hope that we do not), I
agree with Melles-Griot, ...

No you don't, and your disagreement is more than obvious to any informed
casual observer. You remind me of a fellow employee from the 70's. I asked
him what he would do if his wife caught him in bed with his neighbor's wife
(as I did) and he answered, "I'd just deny it."
--
73, Cecil http://www.qsl.net/w5dxp

Antenna reception theory
 

Cecil,

If this is name-dropping poker, I'll see your Hecht and raise with J.D.
Jackson and Born & Wolf.

But thanks for the education. After 40 years of obtaining multiple
degrees in physics followed by working R&D in the optics field I guess I
still need to seek out some "real-world physicists" to figure out that
energy is indeed something to "worry about". I never would have imagined
such a thing!


73,
Gene
W4SZ

Cecil Moore wrote:
Gene Fuller wrote:

Yes, most people with rudimentary arithmetic skills would agree that
75 plus 8.33 does not equal 133.33.


Too bad Dr. Best posted the equation: "Ptotal = 75w + 8.33w = 133.33w"
on this newsgroup (and, thank goodness, left it out of his article) so
he obviously disagreed with you at the time. He also said that interference
had nothing to do with it.

However, anyone even remotely familiar with waves would readily
understand that the component waves Cecil loves to talk about are
merely mathematical conveniences. It is entire possible to set up
other model configurations, such as a combination of a one traveling
wave and one standing wave.


What happens at an impedance discontinuity given those circumstances? To
find out, read my WorldRadio article, Part I of which is posted on my web
page. Part II will be posted after Christmas. At the risk of raising your
politically incorrect ire as I have done with this technical posting,
MERRY CHRISTMAS!.

In order to make his model work, Cecil needs to invoke the mythical P3
and P4 on the source side of the reflection discontinuity. He never
gets around to explaining how these two waves, which exactly cancel at
all points in space and at all times, can contain any energy at all.


The answer is simple. Do waves contain any energy at all? Do waves that
cancel contain any energy? If waves contain no energy, they cannot exist,
and therefore are incapable of canceling. If they exist and cancel, they
contained energy just before their cancellation. Any way you cut it,
my approach is consistent with the laws of physics as enumerated in
"Optics",
by Hecht, and yours leads to a contradiction of those laws of physics.

The reason that most practitioners of wave models solve for the fields
first and then worry about power or energy is:

a - This procedure works correctly all the time.


Yes, it does. But optics engineers didn't have the luxury of dealing
with voltages and currents. They had to solve the problem using powers.
And they did exactly that decades ago. That RF engineers refuse to
consider the laws of physics concerning EM waves developed by optics
engineers is absolutely astounding to me. W7EL put it best, something
to the effect that if it wasn't invented here, we don't want to hear it
(even if it is right). But I daresay that Eugene Hecht knows much more
about EM waves that you will ever know, given your closed mind.

I do not expect to change Cecil's mind. Other than his own potential
embarrassment from the silly publications in World Radio, his folly is
harmless.


You are just displaying your extreme ignorance, Gene. My "WorldRadio"
article
corrects some of the *conceptual* errors in Dr. Best's QEX article but
otherwise
contains the same equations as his article. If you disagree with me, you
are
also disagreeing with Dr. Best's equations, i.e. you are between a rock
and a
hard place.

It is interesting that the very people who tell us not to worry about
energy
are the people who get so emotionally rabid when someone chooses to
worry about
energy like real-world physicists do. What do they possibly have to lose
besides
face, self-esteem, sleep, and their pseudo-religious guru status? :-)

Antenna reception theory
 

Richard,

OK, I will turn this right back at you. How do you know that the
countless Faraday screens remove the E-field component from
electromagnetic waves?

"Saying it does not make it so."

Yes, I understand they are used in broadcast transmission lines, and
yes, I understand they take many lightning hits.

Faraday screens are effective. How do you know that they also negate the
fundamental properties of time-varying electric and magnetic fields as
expressed by Maxwell's equations?

73,
Gene
W4SZ

Richard Harrison wrote:
Gene, W4SZ write:
"As has been said many times on this newsgroup, it is not possible to
filter out one field component or the other."

Saying it does not make it so.

Countless Faraday screens are at work removing the E-field component
from electromagnetic waves. Faraday said that the voltage in a coupled
circuit depends only on the rate of change of the magnetic flux through
the circuit. He was refering to induced voltage. It was 1831 when
Michael Faraday observed the interaction between primary and secondary
coils in what was likely the world`s first transformer. Faraday made it
himself and noted that the needle of a galvanometer connected across one
coil deflected briefly whenever he connected or disconnected a battery
across the other coil.

Antenna reception theory
 

Gene Fuller wrote:
If this is name-dropping poker, I'll see your Hecht and raise with J.D.
Jackson and Born & Wolf.

Please post any contradiction of Hecht by your sources. That argument
could get very interesting. To summarize: Constructive interference
energy must come from somewhere in the real world. You seem to disagree.
So where do you think constructive interference energy comes from?

But thanks for the education. After 40 years of obtaining multiple
degrees in physics followed by working R&D in the optics field ...

If you are omniscient, please prove it. If you are not omniscient and
still capable of learning, please admit it. The trouble with gurus is
that they sincerely believe that they know everything already and
therefore cannot possibly learn anything new. I'm still open to learning.
How about you?

... I guess I
still need to seek out some "real-world physicists" to figure out that
energy is indeed something to "worry about". I never would have imagined
such a thing!

That's a really strange thing to admit, Gene, since a very large percentage
of the physics community is dedicated to understanding where the energy
was, is, and will be - down to an almost infinitessimally small amount.
You definitely seem to be cast in the mold of the priests who put Galileo
under house arrest. Are you comfortable with that position?
--
73, Cecil http://www.qsl.net/w5dxp

Antenna reception theory
 

Cecil,

If you know anything about physics, you must know that energy is at the
core of almost all physical analysis.

Sorry that my message was too opaque for you.

73,
Gene
W4SZ

Cecil Moore wrote:
Gene Fuller wrote:


... I guess I still need to seek out some "real-world physicists" to
figure out that energy is indeed something to "worry about". I never
would have imagined such a thing!


That's a really strange thing to admit, Gene, since a very large percentage
of the physics community is dedicated to understanding where the energy
was, is, and will be - down to an almost infinitessimally small amount.
You definitely seem to be cast in the mold of the priests who put Galileo
under house arrest. Are you comfortable with that position?

Antenna reception theory
 

A short while ago, I explained why your Faraday cage doesn't separate E
and H as you claim. Exactly the same explanation applies to this
structure, but with E and H reversed. It locally modifies the E/H ratio
but doesn't separate the field components and it certainly doesn't
remove the E field as you claim.

Roy Lewallen, W7EL

Richard Harrison wrote:
it is just as easy to remove the H-field from the wave as it is to
remove the E-field with a Faraday screen.

To remove the H-field, one sure way is to completely enclose two coils
so they are completely shielded from each other and all electromagnetic
waves. Put the coils in separate metal cans. Put a tiny hole in each
can. Conect one termial of each coil to its end of a coupling capcitor.
Ground the other terminal of each coil.. Ground is the return path for
the coils but it must run on the surfaces of the cans and through the
tiny holes due to skin effect.
Complete shielding removes the H-field as a coupling agent. Only E-field
coupling is provided via the coupling capacitor.

Best regards, Richard Harrison, KB5WZI