what happens to reflected energy ?
 

On Jul 3, 6:13*pm, lu6etj wrote:
... then I asked
you if you can hear sound 80 dB below insect shooting your window.

That reminds me of the medical profession two hundred years ago when
doctors believed that there was no such thing as a virus because they
couldn't see it and besides that, how could it possibly exist and be
alive without a cellular structure?
--
73, Cecil, w5dxp.com

what happens to reflected energy ?
 

On Jul 3, 9:34*pm, lu6etj wrote:
Hi hi, Why I find it more hard to translate your writings than another
guys ones? is it a peculiarity of your playing with words or your zone
manners?

Don't worry about it, Miguel. I am an English major and understand
your English better than Richard's. He is not unlike a court jester
who talks in riddles and takes pride in himself when nobody
understands.
--
73, Cecil, w5dxp.com

what happens to reflected energy ?
 

On Jul 4, 12:02*am, Richard Clark wrote:
You can experience one photon, however could you state that it was not
two instead?

Actually, human rods can detect one photon but that small impulse does
not reach the brain. It takes about nine photons for our brains to
experience photons. It's a transmission line problem, not a detector
problem.

Cecil is among those who cannot be
trusted to write on the white board.

Translation: Don't bother me with technical facts. I am already
satisfied with my present metaphysics. :-)
--
73, Cecil, w5dxp.com

what happens to reflected energy ?
 

"K1TTT" wrote
...
On Jul 4, 8:28 am, "Szczepan Bialek" wrote:
"lu6etj"
...

Hi hi, Why I find it more hard to translate your writings than another

guys ones? is it a peculiarity of your playing with words or your zone
manners? I am sorry because I miss some of your subtleties or
grammatical tricks and I suspect they have more funny meanings that I
can capture :)

Try to understand. Richard gives the free English lessons. I have learnt
a
lot from him.
S*

just nothing about electromagnetics i guess.

Yes. Because I am interested in the antennas and Richard is an expert in it.
In electromagnetics Maxwell and Heaveside are the experts. Available on
line.
S*

what happens to reflected energy ?
 

On Jul 4, 4:19*pm, "Szczepan Bialek" wrote:
"K1TTT" ...
On Jul 4, 8:28 am, "Szczepan Bialek" wrote:

"lu6etj"
...

Hi hi, Why I find it more hard to translate your writings than another

guys ones? is it a peculiarity of your playing with words or your zone
manners? I am sorry because I miss some of your subtleties or
grammatical tricks and I suspect they have more funny meanings that I
can capture :)

Try to understand. Richard gives the free English lessons. I have learnt
a
lot from him.
S*
just nothing about electromagnetics i guess.

Yes. Because I am interested in the antennas and Richard is an expert in it.
*In electromagnetics Maxwell and Heaveside are the experts. Available on
line.
S*

unfortunately you have to learn modern em to know what writings of
maxwell and heaveside to bother believing... they both went through
learning periods before they came to the final transverse wave
formulations. if you read their earlier works you will be mislead
because they were still learning and following dead end paths like
aether theory and fluid analogies.

what happens to reflected energy ?
 

On Jun 30, 5:55*pm, Roy Lewallen wrote:
Keith obviously understands the requirements for energy flow, but a
casual reader might draw the wrong conclusions. . .

Keith Dysart wrote:
. . .
This is quite incorrect. Energy flows must balance, otherwise energy
is being created or destroyed to sustain a difference in flow.

On the average, yes. But not moment-by-moment. Energy can be stored and
retrieved from storage, resulting in unequal energy flow (power) into
and out of a point. For a while. This was explicitly stated earlier when
discussing a capacitor, but I think it's important to make the
distinction here between instantaneous and average requirements. In
steady state, the average condition (energy flow balance) must be met
each cycle. That is, the total energy into a node over a cycle has to
equal the energy out of a node over a cycle.

. . .
Unfortunately wrong. Energy flows must balance as well. Otherwise,
energy is coming from nowhere to sustain the flow.

Ditto.

. . .
Yes, indeed. At that instant, zero energy is flowing from the inductor
to the capacitor. But very soon, energy will be flowing from the
capacitor to the inductor. The balance is that the energy flowing
out of the capacitor is always and exactly equal to the energy flowing
in to the inductor. That is the energy flow balance. The only way for
this not to be true is for energy to be created or destroyed.

Ditto.

. . .
Instead, think that at every instant, the energy flow between the
entities in the experiment must balance.

No, it doesn't, unless I'm misunderstanding the statement. At a given
instant, more energy can flow into a component (e.g., a capacitor or
inductor) than is flowing out, or vice-versa. But in steady state,
whatever flows in during one part of the cycle must flow out during the
remainder of the cycle.

I think you are misunderstanding, possibly because I am not expressing
as clearly as could be. I find it difficult to pick a vocabulary that
will not be confusing due to prior associations with the words. But
then words like 'entity' are too fuzzy.

The system I have in mind has ports through which energy can flow in
or out of the system and components inside the system which can
store energy. For such a system, the energy flowing in to ports
of the system minus the energy flowing out of ports must
equal the increase in energy being stored in the system.

This must be true at all times, or energy is being created or
destroyed; a bit of a no-no.

This system can be subdivided in to sub-systems for which this
energy flow balance must also hold.

As such, if the energy stored in one of the entities (e.g.
capacitor) is increasing, either net energy is flowing in to
the ports of the system, or the energy stored in some other
entity in the system is decreasing (or both). But the sum
of all the flows entering or leaving the ports, plus
the flows between the internal entities must balance on
a moment by moment basis.

Of course the expressions written to describe this will
be dependent on the details of the system. One must also
not forget to account for energy that leaves the system
as heat courtesy resistors. These can be thought of as
ports which only remove energy from the system.

The requirement for moment-by-moment balance is more stringent
than the requirement for average balance. The former inevitably
leads to the latter, but the converse is not true.

From Wikipedia, I have just learned that the concept I am attempting
to describe is known as a "Continuity equation".

Every time one of your instantaneous power curves crosses the zero
axis, power has been destroyed. Every time one of your instantaneous
power curves reaches a peak, power has been created.

I think you may be confused because you are only looking at the
flow in and out of a single entity. This is clearly not conserved.
Nor for that matter is the energy within that entity. It is the
total energy within the system that is conserved, just as it is
the total of the flows of energy between the entities within the
system that must be conserved.

Put more strictly: The sum of all the energy flows in to all of
the entities within the system must equal the energy flow in to
the system.

Again, only on an average or steady-state cycle-by-cycle basis. Great
inequalities can exist for shorter periods.

*. . .

Like Keith, I firmly believe that an instantaneous time-domain analysis
is essential in understanding what really happens to the energy in an AC
system. Averaging reduces the amount of information you have -- if all
you know is the average value of a waveform, you have no way of going
back and finding out what the waveform was, out of an infinite number of
possibilities. If averaging is to be done, it should be done after you
calculate and understand what's going on at each instant, not before you
begin the analysis.

But it's also essential to make absolutely clear what conditions must be
met every instant, such as p(t) = v(t) * i(t), and which must be met
only on the average, such as energy in = energy out.

Roy Lewallen, W7EL

what happens to reflected energy ?
 

On Jul 1, 8:37*am, Cecil Moore wrote:
On Jun 30, 11:29*am, Keith Dysart wrote:

Check the a0 coefficient in the Fourier transform. This represents
the DC component of the signal.

And the result is zero EM waves, either forward or reflected, and your
argument falls apart.

What was my argument that fell apart? I am not the one pushing the
notion
of forward and reflected EM waves. That's you. I am just trying to
help
you fit square waves in to your model.

So how do you characterize a slow square wave? Say one that is 0V for
one year, then 10V for a year, then 0, then...

With several meters of open circuited transmission line, what do you
think is happening on the line for the year while you are waiting for
the
signal to drop back to zero volts? Does it have a constant voltage?
And
0 current for most of that year? Is it an EM wave?

Without this, how would you deal with a signal such as
* V(t) = 10 + 2 cos(3t)

If the cosine term is zero, there are zero EM waves, either forward or
reflected, and your argument falls apart.

Incidentally, V(t) = 10, is a perfect way to prove that energy and the
time derivitive of energy are not the same thing and your argument
falls apart.

You need to read more carefully. I have never claimed they are the
same.

Alternatively, one can use the standard trick for dealing with
non-repetitive waveforms: choose an arbitrary period. 24 hours
would probably be suitable for these examples and transform from
there. Still, you will have zero frequency component to deal
with, but there will be some at higher frequencies (if you
choose your function to make it so).

Windowing doesn't generate EM waves where none exist in reality and
your argument falls apart.

A question for your model...

With an infinitely long transmission line excited by a step function,
is there an EM wave propagating down the line?

If not, what is it that is propagating down the line? Especially at
the leading edge?

....Keith

what happens to reflected energy ?
 

On Jul 1, 8:53*am, K1TTT wrote:
On Jul 1, 12:37*pm, Cecil Moore wrote:





On Jun 30, 11:29*am, Keith Dysart wrote:

Check the a0 coefficient in the Fourier transform. This represents
the DC component of the signal.

And the result is zero EM waves, either forward or reflected, and your
argument falls apart.

Without this, how would you deal with a signal such as
* V(t) = 10 + 2 cos(3t)

If the cosine term is zero, there are zero EM waves, either forward or
reflected, and your argument falls apart.

Incidentally, V(t) = 10, is a perfect way to prove that energy and the
time derivitive of energy are not the same thing and your argument
falls apart.

Alternatively, one can use the standard trick for dealing with
non-repetitive waveforms: choose an arbitrary period. 24 hours
would probably be suitable for these examples and transform from
there. Still, you will have zero frequency component to deal
with, but there will be some at higher frequencies (if you
choose your function to make it so).

Windowing doesn't generate EM waves where none exist in reality and
your argument falls apart.
--
73, Cecil, w5dxp.com

a better argument is that a constant voltage produces a constant
electric field everywhere, since the field is not varying in time or
space there is no time or space derivative to create a magnetic field
so there can be no propagating em wave. *you could do the same with
zero or constant current producing a constant magnetic field.

The same question for you...

With an infinitely long transmission line excited by a step function,
is there an EM wave propagating down the line?

If not, what is it that is propagating down the line? Especially at
the leading edge?

essentially the dc case IS unique in that you must wait forever for it
to reach sinusoidal steady state since the lowest frequency component
is 0hz

You have used similar phrases before. Are you suggesting that an
open circuited transmission line excited with a step function takes
infinitely long to read steady state?

....Keith

what happens to reflected energy ?
 

On 4 jul, 20:53, K1TTT wrote:
On Jul 4, 4:19*pm, "Szczepan Bialek" wrote:





"K1TTT" ...
On Jul 4, 8:28 am, "Szczepan Bialek" wrote:

"lu6etj"
...

Hi hi, Why I find it more hard to translate your writings than another

guys ones? is it a peculiarity of your playing with words or your zone
manners? I am sorry because I miss some of your subtleties or
grammatical tricks and I suspect they have more funny meanings that I
can capture :)

Try to understand. Richard gives the free English lessons. I have learnt
a
lot from him.
S*
just nothing about electromagnetics i guess.

Yes. Because I am interested in the antennas and Richard is an expert in it.
*In electromagnetics Maxwell and Heaveside are the experts. Available on
line.
S*

unfortunately you have to learn modern em to know what writings of
maxwell and heaveside to bother believing... they both went through
learning periods before they came to the final transverse wave
formulations. *if you read their earlier works you will be mislead
because they were still learning and following dead end paths like
aether theory and fluid analogies.- Ocultar texto de la cita -

- Mostrar texto de la cita -

Hello all, friends.

Sorry, I thought we was basically alone in this issue with Richard :)

Then, perhaps some of you can help me if I am not capable to make my
poor english writings intelligible enough. I feel as if Richard had
not pointed in the direction I point. I think that because his
references to S+N/N and others made me think Richard are thinking in
detect low frequency wave quanta at little energy levels, and I am
talking about to perceive the little LF quanta at high energy levels
(large scale oscillators).
In my original example I said we are not able distinguish (today...
tomorrow who knows?) Osc. A from Osc. B, having Osc. A 4*10^28
quanta and Osc. B 4*10^28 +1 quanta, having each 80 m quantum 2.3 *
10^-19 J.

(I know my friend Richard inevitably is going to penalize me for this
"analogy", but it is so beautiful that I could not resist..!) = The
problem is such as distinguish between two zeppelins of about 1500 m^3
each one having zeppelin A only one molecule more than zeppelin B...!
Do not we need an alien Roswell Grey technology for that? :)

Last night I found in the web the "strange word", it is not
"granularity" it is = "graininess", graininess translate to spanish
properly to "granularidad" and granularidad to english as
granularity :)

At the end of this link: http://panda.unm.edu/Courses/Finley/...hermalRad.html
there are a similar text in its original english words =

"Therefore, we see that the quantization of energy simply does not
show up for large-scale oscillators. The smallness of Planck's
constant makes the graininess in the energy much too fine to detect in
those experiments. This is quite similar to the statement that we do
not ordinarily observe the fact that the air in the room is actually
made up of many, many individual molecules. Nonetheless, we can indeed
perform experiments in which this graininess is noticeable, and even
important. Obviously the behavior of the spectral radiancy at very
short wavelengths is one such case. The phenomena involved with the
photoelectric effect, and the Compton effect, are others."

I apologize for my insistence dear Richard, I do not want to be
stubborn but I remember Carl Sagan telling: "Extraordinary claims
require extraordinary evidence" and my posting about the very large
quantum number of the 3.5 MHz Xmtrs play here the "conservative"
role :)

73 to all Miguel - LU6ETJ

PS: Szczepan: Thanks for your info.
Richard: Why a "white board"? has a special meaning? - You are
saying Cecil it is as Dr. House? - Really nice car your RX-7, I envy
you! - My London friend is "missing2 I owe you some answers :(

what happens to reflected energy ?
 

On Jul 1, 10:20*am, Cecil Moore wrote:
On Jun 30, 11:30*am, Keith Dysart wrote:

But you are NOT adding up the energy flows - you are adding up the
power.

Ummm. Energy flow is power. Joules/s!

If it helps, any place I have written 'power', please replace with
'energy flow'.

One too many words - what I meant to say is that you are not adding up
the energy - you are adding up the power. There is no such thing as
conservation of energy flow. That is proved by your own graphs. There
are times when the energy flow is destroyed. There are other points on
your power graphs where energy flow is created.

There is no conflict with conserving flows, ...

The conflict is that conservation of flows doesn't exist. Keith, you
need to go back to college. There is no such thing as conservation of
energy flow so your argument falls apart. When one looks up
"conservation" in a physics book one finds:

conservation of energy principle
conservation of mass-energy
conservation of mechanical energy
conservation of momentum principle

There is NO conservation of energy flow or conservation of power.
Until you give up on that ridiculous concept, we don't have much to
discuss except your religion.

One example you should be familiar with is Kirchoffs Current Law;
it tells you that sum of the FLOWs must equal 0 based on the
Conservation of Charge law. Recall that current is charge per
unit time.

For a more general treatment look up 'Continuity equation' in
Wikidedia where you will find "A continuity equation in physics is a
differential equation that describes the transport of some kind of
conserved quantity. Since mass, energy, momentum, electric charge
and other natural quantities are conserved, a vast variety of
physics may be described with continuity equations.".

Welcome to a new tool for analysis.

What happens when energy = 1 joule, and de/dt = 0 watts. This happens
all the time during an RF cycle so you are not using actual energy
flows. You are using power which goes to zero even when maximum energy
is still present.

Yes, indeed. That is a fundamental possibility and occurs on
transmission lines with infinite VSWR.

If power goes to zero, power has been destroyed. Therefore, there is
no conservation of power principle. Anything that can go to zero, i.e.
can disappear, cannot be conserved.

Power is the time derivitive of energy. They are related
but definitely not one-to-one.

Well, that shoots your argument down. If power and energy do not have
a one-to-one correspondence, then you cannot use the conservation of
energy principle to prove that power is conserved and your argument
falls apart. You must then product a conservation of power principle,
something that every physics professor has warned us doesn't exist.

I can provide any number of references to support the conservation of
energy principle. Please provide just one bona fide reference that
supports your conservation of energy flow (power) principle.

See above, though it seems the common term is Continuity equation.

This is quite incorrect. Energy flows must balance, otherwise energy
is being created or destroyed to sustain a difference in flow.

Good grief! Any physicist knows that is false. Any number of examples
prove that is false.

Energy flows must balance as well. Otherwise,
energy is coming from nowhere to sustain the flow.

Given a black box with an input and output. Measurements of the power
flow vector indicates that the magnitude of each power flow vector is
50 watts and both vectors are pointing inside the black box. How can
the instantaneous energy flows possibly balance?

Inside the box are some elements whose stored energy is increasing
at the same rate.

Instead, think that at every instant, the energy flow between the
entities in the experiment must balance.

You are contradicting yourself. Assume the capacitor *IS* the system
inside a black box. The instantaneous energy flow does NOT balance.

Expand your thinking a bit. Energy is being stored in the capacitor.
You do need to account for this. It is just another flow to track.

It is the
total energy within the system that is conserved, just as it is
the total of the flows of energy between the entities within the
system that must be conserved.

You have it half right. Energy must be conserved. Energy flow is not
conserved.

See above.

Put more strictly: The sum of all the energy flows in to all of
the entities within the system must equal the energy flow in to
the system.

Please see the black box experiment above and balance the energy flow.
Please produce a reference for the conservation of power principle.

See above.

....Keith