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Richard Clark April 6th 07 07:25 AM

Revisiting the Power Explanation
 
On Fri, 06 Apr 2007 00:06:36 GMT, Cecil Moore
wrote:
Superposition is in contradiction to superposition and is in error!

It should be easy to prove.


Stupidity²

Keith Dysart April 6th 07 11:55 AM

Revisiting the Power Explanation
 
On Apr 5, 11:13 pm, Cecil Moore wrote:
Keith Dysart wrote:
This is also true for the
components in our simple generators so superposition holds
there as well.


I've asked Richard how to hook up two IC-706's in
series to get them to meet the requirements of
the superposition principle. Maybe you can show
us how to do it.


Sure, but I thought it would be obvious that there are many
ways, but take the following as an example.

Place them side by side on the bench.
Take a piece of coax sufficiently long to reach between the
output jacks.
Put an appropriate plug on each end of the coax.
Plug the plugs into the output jacks.

....Keith

PS. Was there a real question there somewhere?
What outcome were you expecting to observe?

And there will be no progress until you explain why you think
that superposition and conservation of energy are in conflict.
You have, for years, claimed that conservation of energy holds,
a claim with which there is general agreement.
Only a week ago you started a thread to argue that superposition
holds, another claim with which there is general agreement.
And yet suddenly you are prepared to discard superposition.
Do you not think it worthwhile to examine the reasons to ensure
that you are not making a mistake?
After all, superposition is a powerful technique and none of the
text books mention special caveats that constrain how it can
be applied to generators.
Where is the source of your conflict?






Cecil Moore[_2_] April 6th 07 01:02 PM

Revisiting the Power Explanation
 
Keith Dysart wrote:
On Apr 5, 11:13 pm, Cecil Moore wrote:
Keith Dysart wrote:
This is also true for the
components in our simple generators so superposition holds
there as well.


It is not true for the average commercial amateur
radio transmitter.

I've asked Richard how to hook up two IC-706's in
series to get them to meet the requirements of
the superposition principle. Maybe you can show
us how to do it.


Sure, but I thought it would be obvious that there are many
ways, but take the following as an example.

Place them side by side on the bench.
Take a piece of coax sufficiently long to reach between the
output jacks.
Put an appropriate plug on each end of the coax.
Plug the plugs into the output jacks.


In order to satisfy the results predicted by superposition,
I don't see how you can double the voltage by putting
them in parallel. That's why I asked you to put them
in series. Please put them is series such that the
two component voltages are doubled and the two component
currents are doubled when both transmitters are powered
on.

Also please tell us how the powered-down transmitter
handles the voltage and current that it is exposed
to when the other transmitter is powered up. I
seriously doubt your implication that it is a linear
process.

PS. Was there a real question there somewhere?
What outcome were you expecting to observe?


I am expecting the signal from the powered-on
transmitter not to make it through the circuitry
of the powered-down transmitter. I am expecting
smoke when you try to superpose two coherent 100w
signals into a single 400w signal.

And there will be no progress until you explain why you think
that superposition and conservation of energy are in conflict.


There's a name for people who try to tell others what
they think. I do not think there is a conflict and am
absolutely NOT asserting that the conservation of energy
principle and the superposition *principles* are in
conflict. Such is a figment of your imagination. Please
listen closely:

THE AVERAGE AMATEUR RADIO TRANSMITTER DOES NOT MEET
THE RULES NECESSARY FOR THE SUPERPOSITION PRINCIPLE
TO APPLY! Got it?

There's nothing wrong with the superposition principle.
It simply doesn't apply to certain circuits including
the average commercial amateur radio transmitter.
--
73, Cecil http://www.w5dxp.com

Cecil Moore[_2_] April 6th 07 01:10 PM

Revisiting the Power Explanation
 
Richard Clark wrote:
Cecil Moore wrote:
Superposition is in contradiction to superposition and is in error!

It should be easy to prove.


Stupidity²


Richard, anyone who has to stoop to editing postings
in order to change the meaning is the personification
of stupidity. You have evolved such stupid behavior
into an art form.

I wonder what would think about
your violation of netnews rules?
--
73, Cecil
http://www.w5dxp.com

Richard Clark April 6th 07 04:00 PM

Revisiting the Power Explanation
 
On Fri, 06 Apr 2007 07:10:07 -0500, Cecil Moore
wrote:

I wonder what would think about
your violation of netnews rules?


What a wheeze :-0
Has Hecht split the sheets with you?

73's
Richard Clark, KB7QHC

Jim Kelley April 6th 07 04:42 PM

Revisiting the Power Explanation
 
On Apr 6, 5:02 am, Cecil Moore wrote:

There's nothing wrong with the superposition principle.
It simply doesn't apply to certain circuits including
the average commercial amateur radio transmitter.
--
73, Cecil http://www.w5dxp.com


Hi Cecil -

There are examples of superposition in commercial equipment. Check
out the QSC Audio web page. In particular note the specs on their
stereo power amps in bridged mode.

Your expectation of obtaining 400 watts from two 100 watt radios hints
at a possible error in your understanding regarding simultaneously
superposing voltages and currents. Just a thought.

73, Jim AC6XG



John Smith I April 6th 07 04:59 PM

Revisiting the Power Explanation
 
Richard Clark wrote:
On Fri, 06 Apr 2007 00:06:36 GMT, Cecil Moore
wrote:
Superposition is in contradiction to superposition and is in error!

It should be easy to prove.


Stupidity²


½ ¼ ? ß ? ? ? ? µ ? ? ? ? ? ? ? ? ? ? ± ? ? ? ? ÷ ? ° ? · ? ^(n) ²

IBM extended ascii, ain't it great? grin

JS


Cecil Moore[_2_] April 6th 07 07:13 PM

Revisiting the Power Explanation
 
Jim Kelley wrote:
Your expectation of obtaining 400 watts from two 100 watt radios hints
at a possible error in your understanding regarding simultaneously
superposing voltages and currents. Just a thought.


Put two 70.7 vdc batteries in series with a 50 ohm load.
Switch in one battery at a time. Each battery will
supply 100 watts. Now switch in both batteries. They
will supply a combined 400 watts. The batteries are
required to supply the extra constructive interference
energy assuming each battery maintains its constant
70.7 vdc voltage output.

This is what has to happen when two coherent RF voltages
are superposed in phase. I just don't think an IC-706
will do that, i.e. it is not a linear device, thus
violating the requirements for superposition. In phase
superposition would require that:

Vtot = V1/_0 deg + V2/_0 deg = |V1|+|V2|

Ptot = P1 + P2 + 2*SQRT(P1*P2)cos(0)

Ptot = 100w + 100w + 2*SQRT(100w*100w) = 400w

Presupposition of linearity of any amateur radio
transmitter without proof is foolish as is the
presupposition that a ten cent resistor or a $10
resistor will gobble up all the reflected energy.
--
73, Cecil http://www.w5dxp.com

Cecil Moore[_2_] April 6th 07 07:17 PM

Revisiting the Power Explanation
 
John Smith I wrote:
IBM extended ascii, ain't it great? grin


What is surprising is that if I simply enter a
Shift-6 and a '2', it somewhere gets changed
to that IBM extended superscript squared
character.
--
73, Cecil http://www.w5dxp.com

Jim Kelley April 6th 07 08:35 PM

Revisiting the Power Explanation
 


Cecil Moore wrote:
Jim Kelley wrote:

Your expectation of obtaining 400 watts from two 100 watt radios hints
at a possible error in your understanding regarding simultaneously
superposing voltages and currents. Just a thought.



Put two 70.7 vdc batteries in series with a 50 ohm load.
Switch in one battery at a time. Each battery will
supply 100 watts. Now switch in both batteries. They
will supply a combined 400 watts. The batteries are
required to supply the extra constructive interference
energy assuming each battery maintains its constant
70.7 vdc voltage output.


This is what has to happen when two coherent RF voltages
are superposed in phase. I just don't think an IC-706
will do that, i.e. it is not a linear device, thus
violating the requirements for superposition. In phase
superposition would require that:

Vtot = V1/_0 deg + V2/_0 deg = |V1|+|V2|

Ptot = P1 + P2 + 2*SQRT(P1*P2)cos(0)

Ptot = 100w + 100w + 2*SQRT(100w*100w) = 400w


Presupposition of linearity of any amateur radio
transmitter without proof is foolish as is the
presupposition that a ten cent resistor or a $10
resistor will gobble up all the reflected energy.


Holy cow. Happy Good Friday by the way.

A 100 watt source is something which ostensibly produces a maximum of
70.7 volts and a maximum 1.414 amps into a 50 ohm load. There are two
ways to superpose the outputs of 100 watts sources such as this. One
way is to superpose voltages by arranging them in series. The total
output voltage available would then 141.4 volts. But doing so does
not allow the source to produce current beyond some limit. Maximum
current would still ostensibly be 1.414 amps. To increase the
available current one could arrange the sources in parallel and
basically 'superpose' the currents. However this does not increase
the available voltage. That is still ostensibly 70.7. volts. Total
current from the two sources in parallel into a 50 ohm load would now
be 2.828 amps.

A car battery does not have a 100 watt limit, or in particular, a
1.414 amp limit. When you put two batteries in series you are more of
less superposing the voltages, but you aren't superposing currents.
Since the battery doesn't have a 1.414 amp current limit, the
batteries can each now produce 141.4 volts divided by 50 ohms worth of
current. Since they are arranged in series, each battery will produce
2.828 amps of current. It isn't a superposition thing. Put the
batteries in parallel as a check on your notion of superposition.

Your numbers highlight the problem using irradiance equations with
power terms in them. You're getting the wrong answer because power
doesn't interfere, so it's pretty ridiculous to put it into an
interference equation in the first place. Look at the risk you run
doing it. There is nothing wrong with the proper use of superposition
and interference. Given that, what do you think the problem might be?

73, Jim AC6XG



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