Richard Clark wrote:

On Tue, 01 Mar 2005 18:06:18 GMT, gwhite wrote:

It is about DC to RF efficiency,

Put a number to it.

as I've been pointing out since my
first post, and which you initially commented was "nonsense"

Hi OM,

And so it remains with additional elaborations not quoted here.

but now seem to agree with.

Seeming is a rather insubstantial thing to hang your theories on.

Well they are apparently your's too! Your own example of testing your own PA
said absolutely zip about output-Z. The most you could say is how the circuit
is loaded and its RF/DC efficiency. You're agreeing with me and can't even seem
to recognize it.

"Impedance matching" meant in the normal sense of conjugate
matching for maximum transfer of power

And this reveals the error of "Seeming" because the so-called meaning
you ascribe is this same nonsense.

Here's the original quote [Ken]:

"When the correct matching is done, the antenna works as an impedance mathcing
network that matches the output stages impedance to the radiation resistance."

He brought up "matching to the output impedance" (of the device), not me. There
is no "misinterpretation of meaning" when it comes to making statements about
matching output impedance to a load impedance. The meaning is well-understood
and precise. It means conjugate matching for maximum power transfer, and this
is explicitly sourced from small signal theory. Small signal theory is
oblivious to practical factors like supply rails and efficiency. These
practical factors are paramount in PA design. Thus to apply a theory that
ignores paramount factors is to beg a design which will likely be non-optimal.

Pay more attention to reading
instead of writing.

I'm paying attention, you agree with me but don't have the background to
understand it.

It has been pointed out more than once, and by
several, that Matching comes under many headings. The most frequent
violation is the mixing of concepts and specifications (your text is
littered with such clashes).

No, you still don't get it. I don't have a problem with saying it is
"matched." For example, I said a PA needs to be "load-line matched." This has
a specific meaning, and that meaning explicitly isn't "impedanced matched,"
which means something else. If you don't bother to know what the words mean, I
might as well speak Swahili.

is a misapplied small signal
concept/model. I think that is all I've really been saying.

And I preserved this clash quoted above as an example. If there is
any misapplication, you brought it to the table with this forced
presumption.

There is no forced presumption. The words have explicit definitions. If you
don't know the language, you have no way of communicating.

The misapplication of S parameters to a large signal
amplifier is one thing, to project this error backwards into the
fictive theory that there is some difference between large and small
signal BEHAVIOR (not modeling) is tailoring the argument to suit a
poorly framed thesis.

The models come from behavior and/or device physics, and were developed for the
express purpose of efficient design methodology. Small signal models can (and
do) conveniently ignore large signal concerns such as efficiency and supply
rails, because such concerns are irrelevent in the small signal milieu. To
apply a model to a milieu for which the model is not suited begs a non-optimal
design. The output-impedance concept itself is quite dubious for large signal
amplifiers.

None of your dissertation reveals any practical substantiation, hence
it falls into the realm of armchair theory. We get plenty of that
embroidered with photonic wave theory that is far more amusing.

You are off track.

I read in sci.electronics.design that gwhite wrote
(in ) about '1/4 vs 1/2 wavelength
antenna', on Wed, 2 Mar 2005:

I might as well speak Swahili.


Good idea! Furahini mkaimbe. The wrangling is getting tiresome.
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

On Wed, 02 Mar 2005 19:06:32 GMT, gwhite wrote:
but now seem to agree with.
Seeming is a rather insubstantial thing to hang your theories on.
Well they are apparently your's too!

Hi OM,

From seeming to appearances - leaps of faith are better suited for
debate at the Vatican.

The remainder, unquoted due to repetition of the same basic errors,
has already been commented upon in another posting. Oh, except the
more entertaining jousts:
Pay more attention to reading instead of writing.
I'm paying attention, you agree with me but don't have the background to
understand it.

Mmm-hmm :-)

To be so eagerly embraced as a fellow fool! Something of the chess
equivalent of the sacrificial queen gambit.

73's
Richard Clark, KB7QHC

In article , gwhite wrote:
[...]
Here's the original quote [Ken]:

"When the correct matching is done, the antenna works as an impedance mathcing
network that matches the output stages impedance to the radiation resistance."

Yes, I stand by and have just in another part of the thread once again
explained that indeed the impedance is matched. ie: If you make a small
change in the impedance in any direction the power decreases. Increasing
the resistance is the obvious one. The other three are because the
protection circuits act. The OP had a completed transmitter he was
connecting to a length of wire.



--
--
forging knowledge

Ken Smith wrote:

In article , gwhite wrote:
[...]
Here's the original quote [Ken]:

"When the correct matching is done, the antenna works as an impedance mathcing
network that matches the output stages impedance to the radiation resistance."

Yes, I stand by and have just in another part of the thread once again
explained that indeed the impedance is matched. ie: If you make a small
change in the impedance in any direction the power decreases.

Driven to max swing, this is true. But it is because of asymmetrical clipping,
not because of conjugate mismatch. For lower drives, what you say won't
necessarily be true *unless* you've mis-designed according to conjugate match
ideals. Your argument is circular.

If you design for conjugate match, you're right. I'm saying: don't do that. If
I design for load line match and you design for conjugate max (both pf us using
the same device and supply), I will get a higher peak power than you will.
However, you'll get to be right about how your amp acts regarding diverging from
conjugate load. But it is irrelevent: you made a fundamental mistake.

Increasing
the resistance is the obvious one. The other three are because the
protection circuits act. The OP had a completed transmitter he was
connecting to a length of wire.