Standing morphing to travelling waves, and other stupid notions
 

On Jan 11, 2:12 pm, Jim Kelley wrote:
Cecil Moore wrote:
On Jan 10, 9:23 pm, Jim Kelley wrote:
A standing wave is an amplitude vs position envelope.

A standing wave has an associated envelope but the envelope is *NOT*
the wave itself.
It's like saying the body of a car is the car itself but you have
forgotten the thing that makes the car move - the motor.

Sorry, that is a false statement.

No, in the most general sense, it is a precisely accurate statement.

The equation for a standing wave contains an omega*t term. The
equation for standing waves that does not contain an omega*t term is
the equation for the envelope. Quoting the following reference, page
32: "For problems in which we shall be concerned throughout with
sinusoidal quantities, it is not necessary to write the factor e^jwt
explicitly each time, since it will always be understood that all
terms are multiplied by this factor;"

Please reference "Fields and Waves
in Communication Electronics" by Ramo, Whinnery, and Van Duzer, page
343.

Ah. Apparently the only book you know of that contains the
description of a standing wave.

No, just the only book I brought on my trip.

The equation for the standing wave voltage is: Ez = Efor*e^j(wt-
Bz) + Eref*e^j(wt+Bz)

You must belong to the Standing Wave Equation of the Week Club. Nice
letter choices. :-)

Ramo and Whinnery use E+ and E- but that looks too much like addition
and subtraction when using ASCII characters.

Ah. So according to Cecil, we have a new definition for a wave which
now stipulates that it must only be expressed as a function of time.

Nothing new. The actual standing wave equation is a function of time.
Dropping the time term turns it into an envelope equation. An envelope
is a wave envelope, not a wave. You need to learn to be a little more
precise with the language you choose to use. Looks like you have
forgotten that e^jwt is implied. You need to be a little more precise
with your wording.
--
73, Cecil, w5dxp.com

Standing morphing to travelling waves, and other stupid notions
 

Cecil Moore wrote:
On Jan 11, 2:12 pm, Jim Kelley wrote:

Cecil Moore wrote:

On Jan 10, 9:23 pm, Jim Kelley wrote:

A standing wave is an amplitude vs position envelope.


A standing wave has an associated envelope but the envelope is *NOT*
the wave itself.

No, it's plot of the equation - just like any other plot one might
make of it. It simply a plot of amplitude vs position at a fixed time.

Jeez, Cecil. You really do need a life, man.

By the way, you forgot to give the Poynting vector for a modulation
envelope. :o() (it's a clown) :-)

regards, ac6xg

Standing morphing to travelling waves, and other stupid notions
 

On Jan 11, 12:06 pm, Gene Fuller wrote:

For a plane wave the E and H fields are
perpendicular for either traveling waves or standing waves. For a
coaxial cable operating in the normal TEM mode, the E field is radial
and the H field is circular around the center conductor. Again, the E
field and H field are always perpendicular. Unless one or both of the
fields are exactly zero, the Poynting vector will be nonzero. It will
have a magnitude and direction.

True for traveling waves. ABSOLUTELY *FALSE* FOR STANDING WAVES. Those
false concepts are the source of your (and others) confusion.You
should have paid attention to my postings of those two very different
equations.

The E and H fields are 90 degrees apart for traveling waves. The cross
product of ExH is the power density in watts/unit-area, i.e. the
Poynting vector. For standing waves, the E and H fields are either in
phase or 180 degrees out of phase. The cross product of ExH for
standing waves is *ALWAYS* equal to zero, i.e. the Poynting vector for
pure standing waves is always equal to zero. Please alleviate your
ignorance on this subject and get back to us. There is ZERO real power
in a pure standing wave. The Poynting vector for a standing wave is
*ALWAYS* zero contrary to what you falsely assert above.

Stating the same thing in voltage and current terms, for a traveling
wave, the voltage and current are either in phase for forward waves or
180 degrees out of phase for reflected waves. Either way, the real
power in the traveling wave is V*I watts.

For a standing wave, the voltage and current are 90 degrees out of
phase. The real power in the standing wave is ZERO! P = V*I*cos(90) =
0
--
73, Cecil, w5dxp.com

Standing morphing to travelling waves, and other stupid notions
 

On Jan 11, 4:04 pm, Jim Kelley wrote:
Cecil Moore wrote:
A standing wave has an associated envelope but the envelope is *NOT*
the wave itself.

No, it's plot of the equation - just like any other plot one might
make of it. It simply a plot of amplitude vs position at a fixed time.

I'm glad you finally agree.
--
73, Cecil, w5dxp.com

Standing morphing to travelling waves, and other stupid notions
 

Cecil Moore wrote:
On Jan 11, 12:06 pm, Gene Fuller wrote:

For a plane wave the E and H fields are
perpendicular for either traveling waves or standing waves. For a
coaxial cable operating in the normal TEM mode, the E field is radial
and the H field is circular around the center conductor. Again, the E
field and H field are always perpendicular. Unless one or both of the
fields are exactly zero, the Poynting vector will be nonzero. It will
have a magnitude and direction.

True for traveling waves. ABSOLUTELY *FALSE* FOR STANDING WAVES. Those
false concepts are the source of your (and others) confusion.You
should have paid attention to my postings of those two very different
equations.

The E and H fields are 90 degrees apart for traveling waves. The cross
product of ExH is the power density in watts/unit-area, i.e. the
Poynting vector. For standing waves, the E and H fields are either in
phase or 180 degrees out of phase. The cross product of ExH for
standing waves is *ALWAYS* equal to zero, i.e. the Poynting vector for
pure standing waves is always equal to zero. Please alleviate your
ignorance on this subject and get back to us. There is ZERO real power
in a pure standing wave. The Poynting vector for a standing wave is
*ALWAYS* zero contrary to what you falsely assert above.

Stating the same thing in voltage and current terms, for a traveling
wave, the voltage and current are either in phase for forward waves or
180 degrees out of phase for reflected waves. Either way, the real
power in the traveling wave is V*I watts.

For a standing wave, the voltage and current are 90 degrees out of
phase. The real power in the standing wave is ZERO! P = V*I*cos(90) =
0
--
73, Cecil, w5dxp.com


Cecil,

That is utter nonsense. Back to school for you. You are confusing phase,
vector direction, phasors, and most everything else. What a mess!

Everything I said above is exactly correct.


73,
Gene
W4SZ

Standing morphing to travelling waves, and other stupid notions
 

Cecil Moore wrote:
On Jan 11, 12:10 pm, Gene Fuller wrote:
What do you recommend as the definitive reference on "the nature of
photons and photonic waves"?

I personally like "Optics" by Hecht and his idea that standing waves
maybe shouldn't be called waves at all. EM waves move energy and
conserve momentum. Standing waves don't.
--
73, Cecil, w5dxp.com

That was a joke. I doubt that Hecht even uses the exact term "photonic
wave". For fun, try a Google on "photonic wave". Most of the entries are
really weird stuff.

Wave-particle duality means that light and other electromagnetic
phenomena can be described in terms of waves or in terms of photons.
There is no need to use both descriptions at the same time. The laws of
physics are complete for either.

73,
Gene
W4SZ

Standing morphing to travelling waves, and other stupid notions
 

On Jan 11, 8:32 pm, Gene Fuller wrote:
Wave-particle duality means that light and other electromagnetic
phenomena can be described in terms of waves or in terms of photons.
There is no need to use both descriptions at the same time. The laws of
physics are complete for either.

Actually, what you don't seem to realize is that exactly the same laws
apply to both at the same time and all those laws are perfectly
consistent. Photons cannot stand still. Therefore, standing waves are
not photonic, i.e. they are not EM waves. That you assert the standing
wave E-field and H-field are 90 degrees apart is insanity (in addition
to being completely false).
--
73, Cecil, w5dxp.com

Standing morphing to travelling waves, and other stupid notions
 

On Jan 11, 8:27 pm, Gene Fuller wrote:
Everything I said above is exactly correct.

Sorry Gene, almost everything you said about standing waves is false
and some simple math will prove it. Please stop acting like a spoiled
brat long enough to understand the following facts of physics.

Assume the forward wave and reflected wave have the same magnitude. At
one point on the line:

The forward voltage is 100v at 0 deg and the forward current is 1 amp
at 0 degrees.

The reflected voltage is 100v at 90 degrees and the reflected current
is 1 amp at 270 degrees. Perform the simple phasor addition to find
the magnitude and phase of the standing wave at that point.

The standing wave voltage is 141v at 45 deg and the standing wave
current is 1.414 amps at -45 deg. The standing wave voltage and
current are *always* 90 degrees apart which means the standing wave E-
field and H-field are necessarily either zero or 180 degrees apart.

141*1.414*cos(90) = zero watts = ExH = E*H*sin(A) = standing-wave
Poynting vector

Therefore, the angle A between the standing wave E-field and H-field
is either zero or 180 degrees. That doesn't meet the definition of a
TEM wave. Therefore, standing waves are *NOT* TEM waves and Hecht was
right about that notion.

Until you (and others) hit the books and correct your false concepts,
you are going to continue to exhibit your considerable ignorance of
this subject, your alleged education notwithstanding.

I believe that, in the long run, the technical truth will will out
over all the ignorance, obfuscation, and ad hominem attacks.
--
73, Cecil, w5dxp.com

Standing morphing to travelling waves. was r.r.a.a Laugh Riot!!!
 

"AI4QJ" wrote in
:


"Michael Coslo" wrote in message
...

And there are some sanctimonius people out there who are educated
orders of magnitude beyond their intelligence,

Gosh, I apologize. I did not realize I was communicating with someone
of such a greater IQ than I. Can you tell me your MENSA number or
perhaps where you recived your PhdD?

ready to throw out veiled
insults at the drop of a hat.......

Fortunately no one like that is in this conversation, eh?

Well, there was the one person who started this exchange with a very
sarcastic comment. I'm not sure who it was but this mystery person
said:

"Oh darnit! Here I went and built several antennas designed with
Eznec, and they have worked just like the program said they would.

I guess I'll have to take the remaining ones down, since I was
only
supposed to discuss them, not actually make and use them. Thanks for
the correction!"

Unexpected and unnecessary sarcasm pointed in my direction tends to
make me appear sanctimonious and to respond in kind.


That was me. Forgive the sarcasm. Sometimes that doesn't come
across well in posting.

I'll be straightforward.

Your comment about Eznec as you quoted...


The NEC program is just a computer model, for discussion purposes only.

End qoute

That statement is absolutely wrong.

I have designed antennas using the program. I have studied the presumed
properties of these antennas. I have put these antennas together.

Upon testing and use of these antennas, they have worked in a manner
consistent with the way the program predicted that they would.

- Mike -

Standing morphing to travelling waves, and other stupid notions
 

On 9 Jan, 22:25, Roy Lewallen wrote:
After reading this, I understand why you find Art's material interesting.

snip
Roy Lewallen, W7EL


You just cannot stop the sarcasm coming out against posters can you?
What did you gain on this gotcha?
Art