On Wed, 26 May 2004 10:34:57 -0500, "Steve Nosko"
wrote:
Hey! I know it HAD to be a PREGNANT Chicken that came first...


Well actually....

One explanation I've read (Scientific American, I think) offered that
some folks believe that chickens have eggs to get more chickens.
Wrong. Eggs have chickens to get more eggs.

Another superposition issue. ;-)

73's
Richard Clark, KB7QHC

On Thu, 27 May 2004 10:49:25 -0500, Cecil Moore
wrote:
It's clear that R.C. loves tweeking Cecil.

Trouble is, I usually have no idea what his random ramblings
are all about.

Steve, perhaps you should repeat your observation with easier words.

Cecil Moore wrote:

Jim Kelley wrote:

Tam/WB2TT wrote:
Seems to me that once you
have put all the energy into the TL that it can store, you don't have to
supply any more energy (?)

BINGO!! No more _energy_ flows - until or unless something changes.
(TV signals are of course always changing.)

Of course, you are talking about *NET* energy above.

Right. There isn't another kind.

73, Jim AC6XG

Cecil Moore wrote:
It's a very condensed verion of the reams of stuff that some posters have
posted over the past year. In particular, when I tried to introduce noise
and modulation to prove my point, I was told that noise and modulation are
not allowed during steady-state.

Stands to reason. Intentionally absent from the steady state are noise,
modulation, transients, and any other perturbation. It would be kinda
like opening the lid of an adiabatic chamber in order to see if the
internal temperature stays constant.

73, Jim AC6XG

Gene Fuller wrote:
* Standing waves don't require the pre-existence of traveling waves.

Please present an example of a standing wave that exists without
a forward-traveling wave component superposed with a rearward-
traveling wave component.
--
73, Cecil http://www.qsl.net/w5dxp

Cecil Moore wrote:

Jim Kelley wrote:

Cecil Moore wrote:
Of course, you are talking about *NET* energy above.

Right. There isn't another kind.

That goofy assertion doesn't even merit a response.



Following your logic, two people shooting at each
other with identical bullets can do no harm because
the net energy is zero. Care to prove your theory?

How many sources ya got in that example, Cecil? Is that the same to
you? If it is, then I can see why you don't understand.

73, Jim AC6XG
73, Cecil http://www.qsl.net/w5dxp

Jim Kelley wrote:

Cecil Moore wrote:
Of course, you are talking about *NET* energy above.

Right. There isn't another kind.

That goofy assertion doesn't even merit a response.

Following your logic, two people shooting at each
other with identical bullets can do no harm because
the net energy is zero. Care to prove your theory?
--
73, Cecil http://www.qsl.net/w5dxp

Jim Kelley wrote:

Cecil Moore wrote:
It's a very condensed verion of the reams of stuff that some posters have
posted over the past year. In particular, when I tried to introduce noise
and modulation to prove my point, I was told that noise and modulation are
not allowed during steady-state.

Stands to reason.

By no stretch of the imagination, can that be dubbed "reason".

"Steve Nosko" wrote in message ...
OH! NO! Vortex vs. Bernoulli

Actually, it's Circulation vs. Newtonian vs. Bernoulli -- all three
are different mathmatical means of describing accurately and precisely
what happens when a airfoil produces lift. Actually each is simply a
different way of expressing exactly the same thing, but none of them
translates well to a real-life understanding of the concept. One of
the problems is that causes and effects get confused and
oversimplified by the math.

Much the same with reflections, transmission lines, and impedance
matching. While reflections do indeed exist on transmission lines when
mismatched to a source or load, they simply create standing waves.
Standing waves create non-optimum impedances depending on the
characteristics and length of the line. These impedances interact with
source and load impedances in very predictable and calculated ways.
Efficiency of power transfer is then determined by optimizing the
matching of these impedances. Optimimizing impedances then eliminates
reflections --- a circle of causes and effects.

Mathmatically, it's more expedient to skip much of the in-between
cause-and-effect stuff, and jump directly to describing the entire
process as a direct relationship between reflections and power
transfer -- which causes problems when attempting to visualize or
explain the process -- because that's not the way it really works.
It's not quite that simple and direct.

A standard SWR meter is a good example. It can't conveniently measure
reflections OR standing waves, so it measures mismatch. Since
everything is directly related, it could be said that it measures
reflections -- but it really doesn't. So, it doesn't really matter
unless you try to understand how the meter works in terms of how it
measures reflections or standing waves.

Al

Cecil Moore wrote:
Gene Fuller wrote:

* Standing waves don't require the pre-existence of traveling waves.


Please present an example of a standing wave that exists without
a forward-traveling wave component superposed with a rearward-
traveling wave component.
--
73, Cecil http://www.qsl.net/w5dxp



Cecil,

Sorry, you are not paying attention.

I gave you a reference that is full of such examples. Another reference
you have quoted on numerous occasions is "Transmission Lines and
Networks" by Walter Johnson. Take a look on page 164. He gives a
description of standing waves and then comments, "One can imagine two
oppositely traveling waves, . . . "

Note that he uses "imagine", not required, essential, or any other
mandatory word.

I do not claim the use of superposed traveling waves is wrong. However,
it is merely a mathematical trick, not unlike describing a square wave
as a summation of Fourier components. This is very commonly done, and it
is often very useful. It does not mean that mathematically derived
sub-components are somehow more valid representations of nature than the
original form.

73,
Gene
W4SZ