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[email protected] September 19th 03 05:55 AM

Cecil Moore wrote:

wrote:
I have often suspected that it is the existence and use of 'Bird watt'
meters that has convinced so many of the existence of forward and
reverse power; a belief which many seem absolutely unwilling to
relax their hold on despite the difficulties it causes them.


OTOH, a TDR causes you difficulties. And just how do you explain
standing waves without a forward wave and a reflected wave?


Can you expand on why you think a TDR causes me difficulties?
I can't think of any reasons.

As for standing waves, I have no difficulties with forward
and reflected voltage waves. They work perfectly fine.

....Keith

[email protected] September 19th 03 05:58 AM

Cecil Moore wrote:

wrote:
Of course if you let go of Pfwd and Pref and just used Vfwd and Vref
you would quickly learn that you had no interest in Pfwd and Pref
and thus your inability to determine them would not cause you
much distress.


Uh Keith, radiated *POWER* is what we are trying to get from our
antennas.


Yes indeed. Net power. The only power that counts.
Pnet = average( v(t) * i(t) )

Forget that forward and reverse stuff. That's not what is radiated.

....Keith

Cecil Moore September 19th 03 01:00 PM

Roy Lewallen wrote:
I've done my analysis, and am satisfied with it. That's why I don't
rearrange things to suit your view of reality.


I've never before seen a person so proud of a contradiction. If reflected
power is greater than forward power, then the Poynting vector points away
from the load, but you have said it doesn't. So which is it?

Why are you unable to calculate the correct terms, collect them, or
whatever you think necessary, and show us what values they are and how
they add up to give us the forward and reverse powers you hypothesize?


I don't choose to waste my time on such a no-brainer issue. If the Poynting
vector points toward the load, the reflected power cannot be greater than
the forward power. Chipman goes out of his way to indicate that such an
apparent contradiction is caused by a resonance effect. The opposite sign
of the reactance of Z0 Vs the load is re-reflecting energy back to the load
because the load resistance is in series with the inductive reactance of the
load and the capacitive reactance of the feedline. The re-reflected energy
supplied by the capacitive reactance becomes forward power in the resistance.
That's why the Poynting vector points toward the load. According to Chipman,
that's why forward power minus reflected power CANNOT be negative.
--
73, Cecil http://www.qsl.net/w5dxp



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Cecil Moore September 19th 03 01:07 PM

wrote:
Can you expand on why you think a TDR causes me difficulties?
I can't think of any reasons.


There's more than just voltage in those returned pulses.

As for standing waves, I have no difficulties with forward
and reflected voltage waves. They work perfectly fine.


That takes care of the E-field. But do you think a wave can exist
without an H-field? If not, the wave possesses energy, by definition.
Energy flowing past a point is power.

Your voltage-only waves violate the conservation of energy
principle and the accepted laws of physics for EM waves.
--
73, Cecil
http://www.qsl.net/w5dxp



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Cecil Moore September 19th 03 01:11 PM

wrote:
Forget that forward and reverse stuff. That's not what is radiated.


Uh Keith, power delivered to the antenna equals forward power minus
reflected power. I notice you have not provided a way for standing
waves to develop without the existence of reflected waves. Do you
also believe that standing waves don't exist?
--
73, Cecil
http://www.qsl.net/w5dxp



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Cecil Moore September 19th 03 01:14 PM

wrote:
When you use a pulse, p(t) = v(t) * i(t) shows the pulse going
by and coming back too, if it reflects. But for that, you have to
look at things in the time domain, something a number of readers
here refuse to do for continuous sinusoidal excitation. When you
look at continuous sinusoidal excitation in the time domain all
the information you need about power is provided without having
to resort to Pfwd and Prev.


Yes, but those steady-state shortcuts often lead to a distorted
view of reality. Exactly what magic happens at the instant when a
system goes from the transient state to steady-state?
--
73, Cecil
http://www.qsl.net/w5dxp



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David Robbins September 19th 03 02:58 PM


"Cecil Moore" wrote in message
...
Yes, but those steady-state shortcuts often lead to a distorted
view of reality. Exactly what magic happens at the instant when a
system goes from the transient state to steady-state?


there is no magic, and real systems can never get to steady state. the
steady state approximations are used by engineers who understand their
limitations and know when they can apply them to easily get answers that are
good enough for every day use. engineers who don't understand them can
always use the full field equations and calculate the exact answers if they
have the time and enough information about the system... but they will never
be able to answer the question about forward and reflected power except at a
specific instant in time and single location in the system as the transients
never go away and power in is never equal to power out except by
coincidence.



Richard Clark September 19th 03 05:02 PM

On Fri, 19 Sep 2003 07:07:35 -0500, Cecil Moore
wrote:
Your voltage-only waves violate the conservation of energy
principle and the accepted laws of physics for EM waves.


Hi Cecil,

Problems of speed reading again afflict you. Or is it the phenomenon
of copy machine hypnosis, where with each sweep of the light you
acquire more virtual education? That technique works better if you
hold single pages up instead while looking down through sunglasses.
(Not nearly as expensive as tuition by the way ;-)

From Chipman (no point in offer the page # is there?):
"Postulate 4. At the intersection of any transverse
plane with the line conductors there is a unique
value of potential difference between the conductors
at any instant..."

As you reject Postulate 4 explicitly in your statement(s), you also
reject your own arguments couched in Chipman's discussion that you
cut-and-paste into your derivative works.

Next time you ride your bike to the library, take the time to read
Chipman's work instead of copying it. Given the nearly universal
silence in this group to such insights offered above in the quote, it
seems you should be in rather crowded circumstances competing to read
that same volume - none here seem to have time to read nor quote the
obvious.

The kulture of Institutionalized Ignorance festers on.

73's
Richard Clark, KB7QHC

Richard Clark September 19th 03 05:21 PM

On Fri, 19 Sep 2003 13:58:36 -0000, "David Robbins"
wrote:
"Cecil Moore" wrote in message
...
Exactly what magic happens at the instant when a
system goes from the transient state to steady-state?


there is no magic, and real systems can never get to steady state. the
steady state approximations are used by engineers who understand their
limitations and know when they can apply them to easily get answers that are
good enough for every day use.


Hi David,

This is the difference between Engineering and religion. All
Engineering works with error and simply states the limits of
confidence to known factors. That is 1 Ohm/Volt/Ampere to a tolerance
of 20% or 10% or 5% or better. When differences between known
boundary conditions far exceed the error of their determination, then
you can rest assured that you have a solution that is an accurate
portrayal of those different boundary conditions. (On reflection,
even religion acknowledges error; so comparisons are an affront to
that study as well. What goes on in these "debates" is simple,
narcissistic laziness.)

I offered a simple line loss problem some time ago to which there was
only one correct submission (be e-mail no less). This problem
approached this "debate" with known errors and the correspondent found
a solution to within 0.06 dB while others, frozen in mental gridlock,
failed to even choose the conventional "perfect" answer. In the work
place they would be staring at the bench, transfixed in the agony of
Zeno's paradox, while real techs (not even engineers) would have the
problem whipped before the first break (and still had done productive
work too).

73's
Richard Clark, KB7QHC

Cecil Moore September 19th 03 05:21 PM

Richard Clark wrote:
From Chipman (no point in offer the page # is there?):
"Postulate 4. At the intersection of any transverse
plane with the line conductors there is a unique
value of potential difference between the conductors
at any instant..."

As you reject Postulate 4 explicitly in your statement(s), ...


Richard, you really need to grasp the difference between exclusive
and inclusive statements. Keith implies a voltage-only wave. It
is my understanding that an EM wave cannot exist without an
associated H-field. Chipman doesn't say EM waves can exist
without an H-field. EM waves possess both E-fields and H-fields.
The power associated with an EM wave is E x H. An H-field around
a wire implies a current in that wire. My objection to Keith's
statement is his voltage-only wave existing without current, energy,
or power.
--
73, Cecil, W5DXP



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