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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 |
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? |
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 |
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 |
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 |
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 |
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 |
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 |
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 |
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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