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#1
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![]() W5DXP wrote: Jim Kelley wrote: You were the topic of discussion of this post, Cecil. It certainly wasn't techincal, but I do think it was accurate. An ethical person would apologize. How about you? After you, sir. ac6xg |
#2
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Jim Kelley wrote:
W5DXP wrote: An ethical person would apologize. How about you? After you, sir. OK, I apologize for any and all angst that I have caused you (or anyone else on this newsgroup). My Dad and my best friend both died this year and I have been in a foul angry mood for most of the time. I would like for you and me to lay our personality conflicts to rest, but based on your past actions and reactions, I really don't think you are capable of being a gentleman. I have a lot of friends with which I differ on technical issues, but you are the only one of them who has ever threatened me. Please prove me wrong about my opinion of you. I have removed your address from my email kill file. -- 73, Cecil, W5DXP |
#3
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W5DXP wrote:
OK, I apologize for any and all angst that I have caused you (or anyone else on this newsgroup). My Dad and my best friend both died this year and I have been in a foul angry mood for most of the time. I accept your apollogy. I also lost my dad. He died last month and I was at his side for his last days. I would like for you and me to lay our personality conflicts to rest, but based on your past actions and reactions, I really don't think you are capable of being a gentleman. I have a lot of friends with which I differ on technical issues, but you are the only one of them who has ever threatened me. Please prove me wrong about my opinion of you. Well, that didn't last very long. I have never threatened you. I don't threaten people. Every one of my personal friends knows me as a truely gentle man. I find it difficult to see how I could ever change your opinion about anything. As you may recall, I was virtually your only supporter on this newsgroup when I joined this quest. I expressed to you my opion that your approach, if correct, was simple, elegant, and beautiful! We seemed to share that enthusiasm in this search for a detailed explanation of the phenomenon. We shared skepticism about reflections from virtual shorts, and agreed that reflections occur only at physical discontinuities. I had discussions with several of the regulars here on the issue, lending support to your point of view about the interference phenomenon. I very much enjoyed that for once we had a common interest and point of view. I've corresponded via email with Steve Best, Walter Maxwell, and others on the issue all prior to having seen part 2 of your paper. After reading part 2 though, I expressed to you that I had reservations about the reversal in the direction of energy described in your paper. I investigated further, and also asked a few of the professors at UC Irvine to consider the problem. The bottom line turned out that there is no physical or mathematical way for such a thing to occur - absent a reflecting media. You wouldn't hear of it. At that point you saw me as your adversary, and began treating me as such. Since then you've called me delusional and impugned my intellegence at almost every opportunity. And yet throughout this whole thing, I've had only one interest. It is the very same one we both shared at the outset, to discover the truth. I've conveyed that truth to you to the best of my ability. And why do you think it is that, through all the insults I've continued to try to convey it to you? It's because I would like to get back to the point once again where you and I share a common viewpoint. That's it. The angst on my part stems from the fact that someone whom I respect, continually finds the need to insult me. Most of the time you'll find I've refrained from commenting on the insults and have simply deleted them. Over the last couple of days however, I spent some time trying to illustrate what that looks like from my point of view. And now we find ourselves here. Of course I appologize for having caused you angst. It was never my intention to cause angst! And it shouldn't have done so. It should only have caused you to reconsider your point of view, and consider another one. I honestly don't believe you have been able to do that - for whatever reasons. Perhaps the case is not unlike that of a scientist who has too much career invested in a particular theory. I don't know. All I know is this is the only less than amicable relationship I have in my life, and I truely wish it were amicable. I have removed your address from my email kill file. I appreciate that courtesy. It's not something I ever thought was necessary. 73, Jim AC6XG |
#4
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Jim Kelley wrote:
I have never threatened you. You deny threatening me with loss of your friendship? -- 73, Cecil, W5DXP |
#5
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![]() W5DXP wrote: Jim Kelley wrote: I have never threatened you. You deny threatening me with loss of your friendship? That's pretty sappy, Cecil. For one thing, although you might care about that, I wouldn't presume to think you'd care about it. For another it's not my MO so, yes. But I've saved all of our correspondence, so if you can quote a date and time, I can look it up. As I've already said, the exchage was a request on my part that you treat me like a friend - as in trying to establish a friendship with you. To put it into context, it was right after you began taking an adversarial stance in our conversations. How you can take that as a threat, I'll never know. Interesting that's the only thing you had a comment on. 73, ac6xg |
#6
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Cecil, W5DXP wrote:
"What does Terman say in Sec. 4-11?" I gave a verbatim response from 4-11 at 11:03am on Jul. 17, 2003. I`ll add the footnote from page 109: "Another way of expressing this situation is to say that the stub position and length are so selected that the input impedance of the line (l1) shunted by the input impedance of the stub-line (a) will equal the characteristic impedance Zo." (l1 is the length of line between the stub and ZL. Fig. 4-17 provides position and length of the stub vs. SWR. The conclusion is that a match is achieved so there is no reflection on the transmission line. The match has eliminated the reflection which was there during the transistion period, but no longer appears there during the steady state. Your Bird wattmeter will show a forward power but no reflected power because the load with its stub provides a match to the transmission line. Best regards, Richard Harrison, KB5WZI |
#7
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Ian, G3SEK wrote:
"---the Bird "wattmeter" is not really a power sensor." The Bird wattmeter indicates the watts, joules per second rate at which energy flows, well enough to be accepted as a world standard portable instrument. Denigrating the Bird is specious because my statement, "Your Bird wattmeter will show a forward power but no reflected power---." is true! The statement only requires the right Bird element to indicate the presence or absence of energy flow in one direction or the other. The Bird is eminently capable. I used the bird because those familiar with it are confident in its ability to separate forward power from reverse power. IEEE defines power as energy in motion, so it could be in perpetual circulation and never used, but it is still power when the volts and amps coincide. Best regards, Richard Harrison, KB5WZI |
#8
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Ian, G3SEK wrote:
"1. The Bird wattmeter does not in fact sense power." The speedometer does not measure miles nor hours, but it can satisfactorily indicate miles per hour. So, what? "2. It only indicates power due to its calibration." Without calibration most instruments only serve as crude indicators. The usual Bird is calibrated for a 50-ohm line which enforces its Zo. Use the common Bird in a different line and its calibration is off. "3. But in this discussion, transmission line theory is under question." I suggested using the Bird as an indicator of transmission line / load match, period. This is based on balance in the directional coupler which is usually good by design and factory adjustment. Many Bird users have adjusted their lload matching networks for minimum reflected power indication. My allusion to the Bird was meant to show that it makes no difference if you have two equal and opposite waves traveling in the reverse direction on a line or no waves in that direction at all. A Bird wattmeter operating properly should indicate zero reflected power. Best regards, Richard Harrison, KB5WZI |
#9
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Richard Harrison wrote:
I suggested using the Bird as an indicator of transmission line / load match, period. This is based on balance in the directional coupler which is usually good by design and factory adjustment. Many Bird users have adjusted their lload matching networks for minimum reflected power indication. As a data point, Using Bird wattmeters, the reflected power was subtracted from the forward during the 75m mobile shootouts to determine the power delivered to the mobile antenna. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 80,000 Newsgroups - 16 Different Servers! =----- |
#10
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Ian, G3SEK wrote:
"What are those V`s and I`s doing in your reply?" Cecil is right on target. Power is VxI. The Bird takes carefully balanced samples of V&I. In the incident wave the samples are in-phase. In the reflected wave the samples are 180-degrees out-of-phase. By exactly balancing the two samples, the reflected wave cancels. Only the incident wave is sensed. To sense the reflected wave only, the polarity of one of the two samples is switched. I am now more dangerous. Until today, I had never seen one of Kraus` books. I now own the third edition of "Antennas (for all applications)". Kraus says there are "fundamental" units and "secondary" units. The "Ampere" is a fundamental unit. All secondary units can be derived from the fundamental units. In the Bird, the given is a 50-ohm line. Power is 50(I)(I), since I=E/R = E/50, and E = 50(I) = V. Power = EI The Bird is accurate enough using a sample of E and a sample of I and scaling to determine power. Multiplication is just scaling or the number of times you repeat a number in an addition column. In the Bird, scaling is an electrical adjustment. Best regards, Richard Harrison, KB5WZI |
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