Richard,

Since we agree the transmission line setup is substantially linear, I'm
not sure we have much to discuss.

I do not agree with you on antenna linearity, but that is another
subject for another rainy weekend, and I'm not the right person to be
discussing that anyway.

73,
Glenn

Hi. How's about you guys going to Dayton.
I'm sure a Tag Fight could be arranged for you all.
Two Pin Falls, Two Submissions,or a KO to decide the winner.

Maybe if you all meet face to face, you will come to some common agreement,
or this thread wii continue ad nausium.

Regards Mike.

Richard Clark wrote:

snip

SBS and SRS (Stimulated Raman Scattering) would be suitable search
engine terms (esp. SBS threshold), but I warn you, they lead to
remarkably dense work where only one link in 20 will be accessible.

73's
Richard Clark, KB7QHC

Thanks.

tom
K0TAR

Richard Clark wrote:
Injecting an electron (current) can achieve the same end.

How accurate are your electron position and velocity
measurements?
--
73, Cecil http://www.qsl.net/w5dxp

Richard Clark wrote:
On Thu, 18 May 2006 19:01:58 -0500, Tom Ring
wrote:


I had not heard of the Stokes shift, nor the scattering you mentioned.
I have some looking up and reading to do. Which, of course, Cecil does
not, since it's not a Xerox moment.


Hi Tom,

It is pretty exotic, it only relates to radiation, reflection,
refraction, heat, and conduction, topics that are alien to discussion
here in more than TV Guide English it appears. Other difficult
concepts include linearity, coherence, mixing, and gain.

Stokes shift is the change in frequency due to the non-linear response
of a media to excitation. Typically the excitation is a photon
interacting with a phonon with radiation scattering following.
Injecting an electron (current) can achieve the same end. The effect
of power clamping in fiber optic transmission lines is due to SBS
(Stimulated Brillouin Scattering) threshold. I've been working with
this (Stokes and Anti-Stokes Shift) for some 20 years, and it fails
easy access through a copier.

The mention came only response to questions of linear response to what
at first glance would be a rather pedestrian transmission line
definition, but Glenn appears to have followed the clown instead of
pursuing his own question - he warned me it may have been pointless.

SBS and SRS (Stimulated Raman Scattering) would be suitable search
engine terms (esp. SBS threshold), but I warn you, they lead to
remarkably dense work where only one link in 20 will be accessible.

73's
Richard Clark, KB7QHC

Hi Richard,
Stokes' law and the Raman effect can be found in
physics texts dealing with quantum mechanics. Georg Joos, in
his book _Theoretical Physics_ deals with such things. The reading
is dense but the underlying concepts aren't too difficult. The
difficulty might lie in understanding how they apply to this
discussion.
73,
Tom Donaly, KA6RUH

On 19 May 2006 03:26:29 -0700, wrote:

I do not agree with you on antenna linearity, but that is another
subject for another rainy weekend, and I'm not the right person to be
discussing that anyway.

Hi Glenn,

By this very post you are discussing it.

Who, in your estimation, does qualify to discuss it? Despite all
outward appearances (and certainly the troll inspired name of the
topic), this is NOT about one-upmanship competition.

73's
Richard Clark, KB7QHC

On Fri, 19 May 2006 15:08:11 GMT, "Tom Donaly"
wrote:

Stokes' law and the Raman effect can be found in
physics texts dealing with quantum mechanics. Georg Joos, in
his book _Theoretical Physics_ deals with such things. The reading
is dense but the underlying concepts aren't too difficult. The
difficulty might lie in understanding how they apply to this
discussion.

Hi Tom,

Certainly Joos would give some entry into the field, but finding work
as accessible outside of a bookstore or library (in other words,
through a search engine) makes for drinking out of a fire hose to
quench a sip's worth of thirst.

Insofar as HOW this applies, I've spoken to that and Tom shows
interest. That alone goes beyond the typical churning that passes for
discussion. The point is that these underlying concepts are fairly
simple as you imply and they are certainly not remote from the usual
topics of consideration here. What they lack is specifics that relate
to our common applications, and there too I've offered discussion.
However, few seem inspired to travel those paths and that fault can
hardly be laid at my doorstep.

73's
Richard Clark, KB7QHC

Richard,

Who, in your estimation, does qualify to discuss it?

I would like to hear from someone who has actually measured the
linearity of a simple antenna. I have not done this, so would only be
one guy with an opinion. Plenty of us around.

By 'simple antenna' I mean an antenna such as a wire dipole without
traps, baluns or other things that could degrade linearity. Since the
linearity of antenna systems in general is in question, the simplest
setup that answers the question would be best.

In the absence of measurement, can anyone comment on the modelling
software? Does it assume and model a linear system? If so, do we know
of any substantial nonlinear departures from the modelling software?

Anyone?

73,
Glenn AC7ZN

Richard Clark, KB7QHC wrote:
"Who. in your estimation, does qualify to discuss it?"

If it`s about antennas, I nominate Kraus. If it`s about mathematics,
many marhematicians qualify.

In algebra, y = mx + b, (the point slope formula), is called linear
because it is the graph of a straight line.

In the discussion of transmission lines and antennas, you must admit
that a uniform transmission line enforces a unique characteristic
impedance (a resistance) on energy traveling in either direction. A
resistance is linear because Ohm`s law prevails. In free-space, everyone
agrees the characteristic impedance is about 377 ohms (a resistance).

Kraus says on page 2 of his 1950 edition of "Antennas":
"Let the transmission line now be connected to a dipole antenna as in
Fig.1-2. The dipole acts as an antenna because it launches a free-space
wave. However, it may also be regarded as a section of transmission line
(see Sec. 1-2). In addition, it exhibits many of the characteristics of
a resonator, since energy reflected from the ends of the dipole gives
rise to a standing wave on the antenna. Thus a single device, in this
case the dipole, exhibits simutaneously properties characteristic of an
antenna, transmission line, and a resonator.

Best regards, Richard Harrison, KB5WZI

wrote:
By 'simple antenna' I mean an antenna such as a wire dipole without
traps, baluns or other things that could degrade linearity.

Seems the easiest measurement of nonlinearity would be the
harmonics (if any) generated by the antenna that do not
appear in the source signal.
--
73, Cecil http://www.qsl.net/w5dxp