On Wed, 15 Oct 2003 10:52:56 -0400, "Tarmo Tammaru"
wrote:


"Richard Clark" wrote in message
.. .
On Tue, 14 Oct 2003 20:32:33 -0400, "Tarmo Tammaru"
wrote:
Hi Tam,

Simulations conform to nature, they do not enforce their own rules and
try to mimic someone's notion of "what should be."


No, I built an actual circuit, using perfect components.

Built? How droll.

If it does not care about coax, this kind of response is an implicit
statement of its being "too hard to manage" so-forget-about-it
approach to changing the problem to suit the answer. In other words,
a model of what? Nothing closer to the original than the oft-quoted
humor of "What is the definition of an elephant? A mouse built to
government specification!"

If you want, I will send you a PDF of the schematic.

And a schematic proves you have "built" a mouse to government
specifications? The amusement "builds."


And so I return to the statement I objected to:
source impedance does not affect SWR.
which is shown no where to have been attempted, and is shown nowhere
to have been proven. What SWR? Where?

I measured the SWR at the point Cecil proposed. I don't recall him
specifying a transmission line either.

You didn't measure anything, you modeled it, and you didn't answer the
question, instead using Cecil's "proposed point" as the scapegoat.
Soon the EE departments across the land will be teaching SWR
measurements to each component lead in a circuit if they follow this
"logic." This syllabus is suitable only for the Laughing Academies.


I note the total absence of technical answers to these specific
questions with proofs of unrelated doodling offered instead.

You want equations, OK.

5) G=R/50

But 5 is precisely the definition of SWR. Therefore G==SWR. Your Bird
wattmeter does exactly this same thing.

An appeal to a bench top instrument? Funny how models at some point
eventually require this anchor that the users insist is unnecessary.
Funnier still is that this whole affair arose of its failure in the
face of inappropriate application, and then the "model" inverting the
logic to prove the inappropriateness was in fact appropriate, which in
turn brings us back to the Bird to substantiate the model.

Next, models of earth, by using short rulers laid against the ground,
will prove it flat. :-)


The condescension of
A simulation of a circuit is better than the "bench".
is absurd, especially when that same simulation fails to confirm bench
experience. I would challenge you to offer the testimony of any
single (credible) author of a simulator to stand by this profundity.

I hate to tell you this, but all complicated designs have been proven in by
simulations for years. Nobody builds a Pentium CPU before they make a chip.
They simulate it.

Aw c'mon Tam, you don't hate to tell me that at all! Nobody built a
4004 before they made it? Your argument is simply the artifice of
myopic reasoning to force the question to the answer.


I note this last effort of yours is one of several iterations - which
simulation was the most perfect? The first or the last? Who is to
know? How is it to be known? Simulation did not describe to you what
you had to change in the simulation to achieve Nirvana. None of your
rationale for change emanated from the data, it sprang from the
experience of someone's bench providing superior results. If this
exercise is so much better, it should have taken only one pass to
accomplish. The negation of that is found in the failed attempts.

In analog simulations there is a tradeoff between accuracy, and how long it
takes. Also, I pointed out that I added opamps to the model so I would not
be loading down the line with 10K resistors.

Not responsive to the question at all. Which Model was the most
perfect in a world where all Models are perfect?

Your response (anticipated) begs the question: Why the need for 10GHZ
GBW Op Amps when a diode, resistor, capacitor, and suitable Radio
Shack meter could do the job? You beg accuracy (the common refuge of
many here so untutored in the subject) when you demonstrate poor
method of accomplishing the measure. Nothing demands 10K resistors
except to satisfy the answer force fitting the question around it.

In my career in Metrology, I measured Hi-Q circuits long, long before
10GHz (or 100MHz, or 1MHz) GBW devices. The poverty of experience is
not a suitable argument proving what was not measured.

Thus the assertion of:
A simulation of a circuit is better than the "bench".
has been shown to be absurd through successive failures by the author
of that statement.

Just for an example, I can make the source impedance anything I want. Do
that on your bench.

In fact I demonstrated this exactly to this specific point, but of
course that evidence is ignored to once again fit the question around
the answer "built." Just like discarding the transmission line that
doesn't fit the answer achieved, discarding my data to charge me with
not having the capacity to do it is of similar caliber.


As I have offered before, there is humor to be found in the disconnect
and this *******ization by Cecil reigns supreme in examples. But to
its credit, it keeps me amused and offers considerable fodder for the
mythical lurker to observe where the logical landmines are (or in
counting the field's litter of amputees attempting pirouettes). ;-)

You have been talking to the Easter Bunny again.
Tam/WB2TT

73's
Richard Clark, KB7QHC


As for equations. It is eminently obvious no "critics" here are going
to utter a line of such work that fills an entire chapter from
Chipman, and is found distributed across other chapters in its
introduction. Even the Easter Bunny would be loath to cite Chipman to
prove Chipman wrong. Talk about impeaching your sources. :-)

I have the advantage here. I could be wrong. I could be shown to be
in error in my reading of Chipman. It hasn't happened. There are
many here who hold copies of his work. There are none who dispute my
recitation at any specific point, nor do they offer statements in his
text expressed by him contradicting my interpretation. My advantage
is that so many here are either lazy if I am wrong, or worse, too
ashamed if I am right. And for such a small matter too. ;-)

It is indeed a poor model that cannot replicate results found from the
math source offered for the unaltered question posed; but the flat
earth society endures and the world tolerates (humors) their model.

73's
Richard Clark, KB7QHC