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Old April 2nd 06, 04:40 PM posted to rec.radio.amateur.antenna
Tom Donaly
 
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Default Coils and Transmission Lines.

Cecil Moore wrote:
Reg Edwards wrote:

It may be of interest to antagonists in the "current through coils"
civil war.



The nature of traveling wave current and standing wave current
is different. Does your program take that into account?

The "current through coils" argument boils down to the ones who
understand standing wave currents in a standing wave antenna and
those who refuse to take the time to understand.

Quoting "Optics", by Hecht: "E(x,t) = 2Eo*sin(kx)*cos(wt)
This is the equation for a STANDING or STATIONARY WAVE, as
opposed to a traveling wave (Fig. 7.10). Its profile does
not move through space. ... [The phase] doesn't rotate at
all, and the resultant wave it represents doesn't progress
through space - it's a standing wave."

Until the gurus take the time to understand the nature of
standing waves in standing waves antennas, they will keep
committing the same mental blunders over and over.


Hecht forgot to put the phase difference in his formula.
It's no wonder there's no phase information in your
standing waves, Cecil, Hecht left it out. Not only
that, but where did he get the idea that it was sin(kx) instead
of cos(kx). I understand Hecht is a good old boy, but I'd like to
see his derivations.
73,
Tom Donaly, KA6RUH
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Old April 2nd 06, 07:39 PM posted to rec.radio.amateur.antenna
Cecil Moore
 
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Default Coils and Transmission Lines.

Tom Donaly wrote:
Hecht forgot to put the phase difference in his formula.
It's no wonder there's no phase information in your
standing waves, Cecil, Hecht left it out.


You are mistaken. If Hecht left it out then so did Gene Fuller.
I suggest you listen to Gene when he says: Regarding the
cos(kz)*cos(wt) terms in the standing wave equation:

Gene Fuller, W4SZ wrote:
In a standing wave antenna problem, such as the one you describe, there is no
remaining phase information. Any specific phase characteristics of the traveling
waves died out when the startup transients died out.

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

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


Not only
that, but where did he get the idea that it was sin(kx) instead
of cos(kx). I understand Hecht is a good old boy, but I'd like to
see his derivations.


Apparently, you are ignorant of the difference in conventions between
optics and RF engineering. In optics, there is no current so there is
no current changing phase at an open circuit. In optics, the M-field
changes directions but not phase. In RF engineering, a change in
direction of the H-field is considered to be a 180 degree phase shift.
Both conventions are correct as long as one understands them. Your
strange statement about Hecht above just proves your ignorance.
--
73, Cecil http://www.qsl.net/w5dxp
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Old April 2nd 06, 09:20 PM posted to rec.radio.amateur.antenna
Tom Donaly
 
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Default Coils and Transmission Lines.

Cecil Moore wrote:
Tom Donaly wrote:

Hecht forgot to put the phase difference in his formula.
It's no wonder there's no phase information in your
standing waves, Cecil, Hecht left it out.



You are mistaken. If Hecht left it out then so did Gene Fuller.
I suggest you listen to Gene when he says: Regarding the
cos(kz)*cos(wt) terms in the standing wave equation:

Gene Fuller, W4SZ wrote:

In a standing wave antenna problem, such as the one you describe,
there is no remaining phase information. Any specific phase
characteristics of the traveling waves died out when the startup
transients died out.

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

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



Not only
that, but where did he get the idea that it was sin(kx) instead
of cos(kx). I understand Hecht is a good old boy, but I'd like to
see his derivations.



Apparently, you are ignorant of the difference in conventions between
optics and RF engineering. In optics, there is no current so there is
no current changing phase at an open circuit. In optics, the M-field
changes directions but not phase. In RF engineering, a change in
direction of the H-field is considered to be a 180 degree phase shift.
Both conventions are correct as long as one understands them. Your
strange statement about Hecht above just proves your ignorance.


Whatever. I'd still like to see his derivations. In your case,
you're using the wrong equation anyway. What you really want is
Beta*l, or the radian length of your transmission line. You can
get that if you know, or can measure the usual parameters in the
transmission line impedance equation, using that equation to solve
for Beta*l. That won't prove your theory because you still haven't
shown that any one transmission line model is unique in terms of
substituting for your coil, but at least it'll give you something
to do.
73,
Tom Donaly, KA6RUH
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Old April 2nd 06, 10:10 PM posted to rec.radio.amateur.antenna
Cecil Moore
 
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Default Coils and Transmission Lines.

Tom Donaly wrote:
Whatever. I'd still like to see his derivations.


"Optics", by Hecht, 4th edition, page 289.

The intensity of a light beam is associated with the E-field
so Hecht's equations are in relation to the E-field.

Speaking of the light standing wave: "The composite
disturbance is then:

E = Eo[sin(kt+wt) + sin(kt-wt)]

Applying the indentity

sin A + sin B = 2 sin 1/2(A+B)*cos 1/2(A-B)

E(x,t) = 2*Eo*sin(kx)*cos(wt)"

Hecht says the standing wave "profile does not move through
space".

I have said the RF standing wave current profile does not move
through a wire.

Hecht says the standing wave phasor "doesn't rotate at all,
and the resultant wave it represents doesn't progress through
space - it's a standing wave."

I have said the same thing about the RF standing wave current
phasor.

Hecht says the standing wave transfers zero net energy. I have
said the same thing about RF standing waves.
--
73, Cecil http://www.qsl.net/w5dxp
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Old April 3rd 06, 05:34 PM posted to rec.radio.amateur.antenna
Tom Donaly
 
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Default Coils and Transmission Lines.

Cecil Moore wrote:
Tom Donaly wrote:

Whatever. I'd still like to see his derivations.



"Optics", by Hecht, 4th edition, page 289.

The intensity of a light beam is associated with the E-field
so Hecht's equations are in relation to the E-field.

Speaking of the light standing wave: "The composite
disturbance is then:

E = Eo[sin(kt+wt) + sin(kt-wt)]

Applying the indentity

sin A + sin B = 2 sin 1/2(A+B)*cos 1/2(A-B)

E(x,t) = 2*Eo*sin(kx)*cos(wt)"

Hecht says the standing wave "profile does not move through
space".

I have said the RF standing wave current profile does not move
through a wire.

Hecht says the standing wave phasor "doesn't rotate at all,
and the resultant wave it represents doesn't progress through
space - it's a standing wave."

I have said the same thing about the RF standing wave current
phasor.

Hecht says the standing wave transfers zero net energy. I have
said the same thing about RF standing waves.


If it's a solution to the wave equation it's o.k., Cecil, but
Hecht is still not using the case where there is a phase difference
between the two waves. If it isn't in the original equation it
won't be in the final version since they're just two ways of
saying the same thing. That's fine because it's the wrong
equation anyway for what you want, which involves impedances
and length, which you probably don't want to deal with because
you're probably under the impression they're just virtual and
not real, and so not worthy of inclusion in your theory.
73,
Tom Donaly, KA6RUH


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Old April 3rd 06, 07:58 PM posted to rec.radio.amateur.antenna
Cecil Moore
 
Posts: n/a
Default Coils and Transmission Lines.

Tom Donaly wrote:
If it's a solution to the wave equation it's o.k., Cecil, but
Hecht is still not using the case where there is a phase difference
between the two waves.


Yes, he is, Tom. The phase *disappears* when you add the two
traveling waves. That you don't recognize that fact of physics
is the source of your misconception. The forward and reflected
wave phasors are rotating in opposite directions at the same
angular velocity. That makes their sum a constant phase value
for half the cycle and the opposite constant phase value for
the other half of the cycle.

I and Richard Harrison have already explained that a number of
times quoting Kraus and Terman.

Here are a number of problems. I(f) is forward current and
I(r) is reflected current. Please everybody, perform the
following phasor additions where I(f)+I(r) is the *standing
wave current*:

I(f) I(r) I(f)+I(r)

1 amp at 0 deg 1 amp at 0 deg _________________

1 amp at -30 deg 1 amp at +30 deg _________________

1 amp at -60 deg 1 amp at +60 deg _________________

1 amp at -90 deg 1 amp at +90 deg _________________

1 amp at -120 deg 1 amp at +120 deg _________________

1 amp at -150 deg 1 amp at +150 deg _________________

1 amp at -180 deg 1 amp at +180 deg _________________

If you guys will take pen to paper and fill in those blanks
you will uncover the misconception that has haunted this
newsgroup for many weeks. If you need help with the math,
feel free to ask for help.
--
73, Cecil http://www.qsl.net/w5dxp
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Old April 3rd 06, 11:05 PM posted to rec.radio.amateur.antenna
John Popelish
 
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Default Coils and Transmission Lines.

Cecil Moore wrote:
(snip)
Here are a number of problems. I(f) is forward current and
I(r) is reflected current. Please everybody, perform the
following phasor additions where I(f)+I(r) is the *standing
wave current*:

I(f) I(r) I(f)+I(r)

1 amp at 0 deg 1 amp at 0 deg 2 A @ 0 deg

1 amp at -30 deg 1 amp at +30 deg 1.72 A @ 0 deg

1 amp at -60 deg 1 amp at +60 deg 1 A @ 0 deg

1 amp at -90 deg 1 amp at +90 deg 0 A @ 0 deg

1 amp at -120 deg 1 amp at +120 deg 1 A @ 180 deg

1 amp at -150 deg 1 amp at +150 deg 1.72 A @ 180 deg

1 amp at -180 deg 1 amp at +180 deg 2 A @ 180 deg

If you guys will take pen to paper and fill in those blanks
you will uncover the misconception that has haunted this
newsgroup for many weeks. If you need help with the math,
feel free to ask for help.


What misconception? That all current in a standing wave has the same
phase, rather than one of two possible phases?
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Old April 4th 06, 12:21 AM posted to rec.radio.amateur.antenna
Tom Donaly
 
Posts: n/a
Default Coils and Transmission Lines.

Cecil Moore wrote:

Tom Donaly wrote:

If it's a solution to the wave equation it's o.k., Cecil, but
Hecht is still not using the case where there is a phase difference
between the two waves.



Yes, he is, Tom. The phase *disappears* when you add the two
traveling waves. That you don't recognize that fact of physics
is the source of your misconception. The forward and reflected
wave phasors are rotating in opposite directions at the same
angular velocity. That makes their sum a constant phase value
for half the cycle and the opposite constant phase value for
the other half of the cycle.

I and Richard Harrison have already explained that a number of
times quoting Kraus and Terman.

Here are a number of problems. I(f) is forward current and
I(r) is reflected current. Please everybody, perform the
following phasor additions where I(f)+I(r) is the *standing
wave current*:

I(f) I(r) I(f)+I(r)

1 amp at 0 deg 1 amp at 0 deg _________________

1 amp at -30 deg 1 amp at +30 deg _________________

1 amp at -60 deg 1 amp at +60 deg _________________

1 amp at -90 deg 1 amp at +90 deg _________________

1 amp at -120 deg 1 amp at +120 deg _________________

1 amp at -150 deg 1 amp at +150 deg _________________

1 amp at -180 deg 1 amp at +180 deg _________________

If you guys will take pen to paper and fill in those blanks
you will uncover the misconception that has haunted this
newsgroup for many weeks. If you need help with the math,
feel free to ask for help.


Cecil, if you don't put any phase information in your
original formula it won't be there when you say the
same thing some other way. But if you
do put it in there, then it has to affect both formulas.
If it disappears, you've done something wrong. If you and
Harrison can't figure out how to extract phase information
from a standing wave you should return your diplomas to
wherever you got them from.
73,
Tom Donaly, KA6RUH
(P.S. Let me give you a hint: first you have to find
out what phase means in a standing wave on a transmission
line. You probably already think you know, though, so I
don't expect you to bother much about it.)
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