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Cecil Moore wrote:
Ian White GM3SEK wrote:
Waves of voltage, yes [1].

Voltage is proportional to the E-field.

Waves of current, yes [1].

Current is proportional to the H-field

Waves of average power, no.

ExH = joules/sec = watts. Are watts the the dimensions
of power? Are the E-field and H-field usually given in
RMS (average) values? Can ExH be considered as the
average power in an EM wave? Are you arguing that
watts are not necessarily power? Are you arguing
that it is not power until it is dissipated?

It can be done easily using forward and reflected waves of voltage
and/or current, but that approach is off-limits for this challenge.
Believers in waves of power shouldn't need it.

"Waves of power" is just a semantic strawman designed
to elicit an emotional response. Anyone using the term
loses technical credibility. It is akin to using the
'N' word to describe race.

How about believers of EM waves containing energy passing
a point? e.g. joules/sec = watts measured at a point?

All this is explained in joules/sec = watts without referring
to volts or amps in my energy analysis article at:

http://www.w5dxp.com/energy.htm

Note that I do not mention "waves of power" anywhere in
my article. What I do talk about is forward energy waves
and reflected energy waves the average value of which can
be measured at a point in joules/sec, i.e. watts.


Cut the other person's text, pepper with strawman questions, throw in a
very ugly smear, and dodge the challenge. Same old Cecil.


--

73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

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Ian White GM3SEK wrote:
Cut the other person's text, pepper with strawman questions, throw in a
very ugly smear, and dodge the challenge. Same old Cecil.

Why must you resort to an ad hominem attack
instead of a point by point technical discussion?
What are you afraid might be revealed by such a
technical discussion?

You know and I know that if we polled the readers
of this newsgroup, no one believes in "waves of
average power". Why you guys feel the need to crucify
that old strawman yet one more time just indicates
how devoid your arguments are of any valid technical
content related to reality. Since it allows you guys
to avoid the actual technical issues, the purpose is
obvious: "Since we are such gurus, blindly believe
what we say."

Here are questions for you and the newsgroup:

1. Who believes in "waves of average power"?
Please don't be shy.

2. Who believes that reflected waves do not
exist?

3. If reflected waves exist, who believes they
can actually exist if they are devoid of joules/sec,
i.e. ExH = zero?
--
73, Cecil http://www.w5dxp.com

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Cecil, W5DXP wrote:
"Waves of power is just a semantic strawman designed to elicit an
emotional response."

It worked. I like the word power. Ronald W.P. King uses it in
"Transmission Lines, Antennas and Wave Guides" on page 245 for example:
"Important properties of transmission circuits (wave guides) of all
types include the following:
1. Low power loss (a) due to heating the conductors and dielectrics of
the circuit itself, and (b) due to radiation.
2. Sufficient power capacity. This implies sufficient spacing of
conductors and adequate dielectric strength of insulating media to
prevent spark discharge; it presupposes conductors with enough surface
to carry large high-frequency currents.
3. An adequate frequency range and a useful frequency response.
4. Physical availability.
5. Special features such as rotational symmetry for swivel points,
invariance in polarization of flexible construction."

Best regards, Richard Harrison, KB5WZI

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Richard Harrison wrote:
Cecil, W5DXP wrote:
"Waves of power is just a semantic strawman designed to elicit an
emotional response."

It worked. I like the word power.

Richard, what would be the dimensions of flowing power?
Wouldn't power flowing past a point be watts/sec or
joules/sec/sec? Have you ever heard of such?

Wave energy flows. The power in the wave is measured at
a fixed point, i.e. the measurement point is NOT moving.

A Bird wattmeter is indirectly measuring the power in joules/sec
*at a fixed point* on the transmission line. The joules are flowing
past a fixed point but the joules/sec power exists at the
measurement point which is NOT moving.

Reflected energy is the energy flowing in the reflected wave.
Reflected power is a measure of that energy flowing past a
fixed point, i.e. the power itself is NOT moving.

"Waves of Average Power" is an oxymoron since waves move
and power doesn't. Be aware that "Waves of Average Power"
is an expression designed to sucker the unsuspected into
a losing argument.
--
73, Cecil http://www.w5dxp.com

my SWR reading
 

Richard Fry wrote:
"Roy Lewallen" wrote:

All the power produced by the transmitter arrives at the antenna
less whatever is lost as heat in the transmission line. There are no
waves of average power bouncing back and forth on a
transmission line. Mathematically separating the power moving
down the line into "forward" and "reverse" components doesn't mean
that waves of average power actually exist.
____________

Roy, I have been involved with the evaluation and repair of FM and TV
broadcast antenna systems where the initial problem was a failure in the
antenna, which then produced a high mismatch between it and the main
transmission line.

The allegedly non-existent nodes along the transmission line for this
condition did a fine job of melting holes in the inner conductor and
Teflon insulators of 3-1/8" OD (and larger) rigid transmission line, at
1/2-wavelength intervals over a considerable length of that line.

What other phenomenon do you believe caused such a result?

Let's suppose for a moment that the holes were melted by reflecting
waves of average power. Why do they repeat every half wavelength? Do the
waves of average power have a phase angle such that they reinforce
periodically? As an engineer, you of course know that the average of a
periodic function is the integral of that function taken over one
period, divided by the period. How then can average power have a phase
angle? Or do the waves not have a phase angle but rather change
amplitude as they travel? If so, what is the mechanism by which they do?
Can you write the equations showing the power at each point along the
line and how it can be greater at half wavelength intervals?

In contrast, the existence of traveling and standing waves of voltage
and current have long been established. You can find a rigorous analysis
of their behavior in a vast number of textbooks. Given the load and
transmission line impedances, you can very quickly calculate, even by
hand and without the use of a computer, the current and voltage at any
point along the line. Unless the line is perfectly matched, there will
be repeating points of high current and of high voltage. Depending on
the nature of the conductor and insulator, either or both of these can
cause localized heating. In the example you gave, the damage is almost
certainly caused by high current rather than high voltage. If you'll
provide me with the impedance of the load and the impedance and velocity
factor of the cable, I'll show that the high current points fall at the
points where the damage occurred. If you tell me the transmitter power
output, I'll also tell you what the current was at those points. Can you
do the same for your theory of power nodes resulting from bouncing waves
of average power? Anyone else having a basic understanding of
transmission line operation can explain your cable damage without any
necessity to imagine bouncing waves of average power.

If you insist on believing that the damage was caused by traveling waves
of average power, please provide an explanation of how these waves
interact to create more power at some points than others. Because power
is the rate of transfer or dissipation of energy, the power into any
point has to equal the sum of the power dissipated at that point and the
power leaving that point, unless that point contains some mechanism to
store energy. Your analysis has to be consistent with this in order to
avoid violating the law of conservation of energy.

I can provide a detailed mathematical quantitative analysis of the
nature of traveling voltage and current waves which explain the
phenomenon you cite. I'm looking forward to your corresponding
mathematical explanation of the phenomenon using traveling average power
waves.

Roy Lewallen, W7EL

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Denny wrote:
There
are no waves of average power bouncing back and forth on a
transmission
line.
************************************************** *******
You really mean that Roy, or am I misreading?

Yes, I mean exactly what I said.

I agree that no 'average' value of power is reflecting, but with a
mismatch at the antenna terminals, voltage/current is definitely
sloshing back and forth on the line making standing waves at .25L
intervals that we can physically probe and measure...

Then we agree on both points.

Roy Lewallen, W7EL

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Cecil Moore wrote:




Here are questions for you and the newsgroup:

1. Who believes in "waves of average power"?
Please don't be shy.

2. Who believes that reflected waves do not
exist?

3. If reflected waves exist, who believes they
can actually exist if they are devoid of joules/sec,
i.e. ExH = zero?

Cecil,

If you ever come to the realization that there is a difference between
transient conditions and steady-state conditions, along with the
realization that standing waves are actually useful, then all of this
mumbo-jumbo about energy coursing back and forth along the entire
transmission line would disappear.

No waves of power needed, average or not.

:D

73,
Gene
W4SZ

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Cecil, W5DXP wrote:
"Waves of Average Power is an oxymoron since waves move and power
doesn`t."

OK, I`m a sucker. I apply power to one end of a transmission line and
power results at the opposite end of the line.

Power did not exist at the far end of the line until it was transported
there by the line. The line moved the power from the 1st place to the
2nd place. It moved!

Best regards, Richard Harrison, KB5WZI

my SWR reading
 

Roy Lewallen wrote:
In contrast, the existence of traveling and standing waves of voltage
and current have long been established.

How can those waves exist without energy? In particular,
how can those waves exist without their energy components
passing a point and being measured in joules/sec?

I can provide a detailed mathematical quantitative analysis of the
nature of traveling voltage and current waves which explain the
phenomenon you cite.

What happens when you calculate ExH in watts? Is it zero?
If not, your whole argument falls apart.
--
73, Cecil http://www.w5dxp.com

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Gene Fuller wrote:
If you ever come to the realization that there is a difference between
transient conditions and steady-state conditions, along with the
realization that standing waves are actually useful, ...

Please explain how those waves can exist without energy,
i.e. without joules/sec passing a point.

No waves of power needed, average or not.

Please stop doing that, Gene. You know that I don't believe
in "power waves". What you are trying to deny is that EM
waves contain energy that can be measured at a point in
joules/sec = watts. That argument just won't fly.
--
73, Cecil http://www.w5dxp.com