You are full of assertions with no proof. You've given me no reason to believe your claim. If you expect me to treat it with anything but disdain, you'll provide at least some justification for it.
I say again,
If you can't measure it, how in blazes can you say anything about it? Specifically, what is your basis for claiming that the model of which it is a part of is incorrect? What is your basis for saying it isn't a Cathodyne?
I say again,
If you can't measure it, how in blazes can you say anything about it? Specifically, what is your basis for claiming that the model of which it is a part of is incorrect? What is your basis for saying it isn't a Cathodyne?
CPaul, if you can't be bothered to find dm6l6.inc model
at Duncan Amps, when I've given a proper page link. How
in blazes can you find time to bother me in PM, whining
that I should email it to you?
I've decided to side with Sy, though he's totally wrong.
Impedance of Cathodyne is now equal. Cause I said so...
This discussion is over.
at Duncan Amps, when I've given a proper page link. How
in blazes can you find time to bother me in PM, whining
that I should email it to you?
I've decided to side with Sy, though he's totally wrong.
Impedance of Cathodyne is now equal. Cause I said so...
This discussion is over.
Well, KenPeter, that's a rational response.
I followed your instructions, repeating what I did before. It still doesn't work. But considering your response here and in your PM, I've lost interest in pursuing the matter. So thank you for your kind considerations. And good luck with your investigations.
I followed your instructions, repeating what I did before. It still doesn't work. But considering your response here and in your PM, I've lost interest in pursuing the matter. So thank you for your kind considerations. And good luck with your investigations.
I been giving this some thought. I think we’re at the end of the trail. Let’s see if we can go out with some clarity.
You know, SY, there’s much we agree on:
You know, SY, there’s much we agree on:
· Burkhart Vogel’s floating source and resistor model gives the right results for time constants (R-C loads) and for voltages (any loads) in a balanced Cathodyne. This model has infinite impedance to ground.
· Your model yields the same results, although it has a value of zero for R?, the impedance between the two sources and ground.
· R? is both un-measurable and non-functional in a balanced Cathodyne.
We part company, though, when you assert that R? must be zero. That raises some questions:· Your model yields the same results, although it has a value of zero for R?, the impedance between the two sources and ground.
· R? is both un-measurable and non-functional in a balanced Cathodyne.
· If R? is unmeasurable, how do you know that it must be zero?
· If R? is non-functional, why is its value constrained in any way?
· If models with both zero and infinite impedances to ground work, then why can’t models with in-between values?
The value of R? is of interest, of course, because the values of Zpg and Zkg depend on it.· If R? is non-functional, why is its value constrained in any way?
· If models with both zero and infinite impedances to ground work, then why can’t models with in-between values?
I didn't assert that about the cathodyne; in the cathodyne, it's an arbitrary value so can be set to zero for both calculational convenience and in recognition of how a cathodyne is actually used.
I did assert that about the incorrect models you presented a few posts back. Even with that resistance of zero, those models give totally incorrect results (my first reaction that with R = 0 your model worked did not bear up to a second, closer look at your circuits, I skimmed over them too quickly, my apologies).
Well, it depends on the model. The ones you posted were wrong and give incorrect results, so the question of R? (whatever it is) is meaningless.
For my model, which DOES give correct results, you can certainly take a resistor between two equipotential points and have it be any arbitrary value- but that's just unremarkably Ohm's law and is true for any circuit. Vogel implicitly recognized this.
For my model, which DOES give correct results, you can certainly take a resistor between two equipotential points and have it be any arbitrary value- but that's just unremarkably Ohm's law and is true for any circuit. Vogel implicitly recognized this.
I'm not going to get off topic and discuss whether you think what I posted was wrong, especially since you haven't even said why you think it was wrong.
So the zero ohm resistor in your model between two sources and ground can be any value, since it is "arbitrary", "non-functional" and "unmeasurable" in a balanced Cathodyne. You chose zero; Vogel, infinity.
Therefore Zpg and Zkg, which directly depend on this resistance, cannot be determined from your model and cannot be measured in a balanced Cathodyne.
So the zero ohm resistor in your model between two sources and ground can be any value, since it is "arbitrary", "non-functional" and "unmeasurable" in a balanced Cathodyne. You chose zero; Vogel, infinity.
Therefore Zpg and Zkg, which directly depend on this resistance, cannot be determined from your model and cannot be measured in a balanced Cathodyne.
Of course they can, and they were- read the article.
Not in a correct model, no, that will change the result. But you can put a nonfunctional resistor in any model of anything and then think you've discovered something wonderful because its value doesn't matter. That's your choice, don't attribute it to me.
I read it. Good data; wrong conclusions. Because as we've agreed, no measurements of a balanced Cathodyne can confirm any value of R? - even that there is a short between the sources and ground. You are essentially arguing that since your model is in accord with what you can measure, the model is correct even in things you can't. Clearly, this is bad logic. So what is your basis for the conclusion since it can't be measurement?
You have yet to explain what is incorrect, what is wrong, about anything you call "wrong" and not "correct". Once again, assertions with no justifications. Where are your justifications?
I can take your model, break the short to ground, and add a 10K resistor between the sources and ground. We've already agreed that such a resistor is non-functional, as was the zero ohm short. By the definition of "non-functional", this cannot change the way the model functions. If it functioned before, it'll still function. Where's the "wrong" in that? Please justify your claim.
And since the choice of the resistor value is, as you said, "arbitrary," so are the claims for the resistances which are based on it- Zpg and Zkg.
You haven't bothered to go back and look at it, have you? It gives totally wrong answers.
There is no short to ground in my model. Please stop mis-attributing things to me.
Assertions again. Prove it. Take us through your claim. Where are your justifications? I've made my case. Where is yours?
Not true - you must be mis-remembering. Figure 3 shows the two sources connected to "common." Figure 2 shows Rk and Rp connected to "common." The only points where Rk and Rp are connected together are the AC "ground" at B+ and ground. Your "common" can only be ground. And your sources are connected to it.
If "common" is not ground, then I could see how you might claim that the plate to common and cathode to common impedances were 1/gm. But then there would no basis left anywhere in the article whatsoever for claiming that Zpgnd and Zkgnd are 1/gm.
So you're saying "take a piece out of one schematic, jam it together with a piece out of another schematic" and then want to attribute that muddle to me and demand I justify it? No thanks.
Try actually looking at your own drawings. You clearly haven't. They give the wrong answer for any pair of loads.
Try actually looking at your own drawings. You clearly haven't. They give the wrong answer for any pair of loads.
I have built a case. Step by step. You say it's wrong, but you give not a single reason. Even when repeatedly challenged to. Not even the courtesy to point out what step in the argument is incorrect. You tell me to go find where the case is wrong, but it is not my place to support your arguments! Shoulder the load, and do your own work. SY, no one can or should accept anything simply on your (or my, or anyone's) say so. And that's what you're asking us to do.
Tell you what. I'll turn your comment around. "SY, try actually analyzing what you are saying. You clearly haven't. Your arguments give the wrong answer in all cases."
See how helpful and persuasive that is? Are you convinced yet?
Fact: BV's model works, just as well and as poorly (depending on the specific result sought) as yours. I invite you to argue that it requires Zpg and Zkg to be 1/gm. Connected to Rk = Rp, it argues that they are about Rk/2 = Rp/2. So is his model wrong?
So no comment on the common / ground thing, huh?
Tell you what. I'll turn your comment around. "SY, try actually analyzing what you are saying. You clearly haven't. Your arguments give the wrong answer in all cases."
See how helpful and persuasive that is? Are you convinced yet?
Fact: BV's model works, just as well and as poorly (depending on the specific result sought) as yours. I invite you to argue that it requires Zpg and Zkg to be 1/gm. Connected to Rk = Rp, it argues that they are about Rk/2 = Rp/2. So is his model wrong?
So no comment on the common / ground thing, huh?
I gave the best reason of all- your model gives absolutely the wrong answers. My model gives correct answers, experimentally verified, which makes it a good model.
Again, just assertions, and no justifications for them. Not even what's wrong about the answers! So let me demonstrate that there is nothing wrong with them.
If we are to evaluate models, which have no physical reality, we can't use bench tests. Our only choices are circuit analysis and simulations. And I'd much rather see you argue with a simulation than with my analysis.
So look below. I've taken your model (R? = 0) and two variations thereof (R? = 13987 and R? = infinity) and simulated the conditions of the bench test you published in your article. The results are identical to one another and in accord with those of your test. There is nothing "wrong" with any of them.
Your choice of R? = 0 is completely arbitrary. Any value from zero to infinity works. Zpg and Zkg are determined in part by R?. This means that they are not determined by your model or by any tests in your article. The article presents no evidence that they equal 1/gm.
If we are to evaluate models, which have no physical reality, we can't use bench tests. Our only choices are circuit analysis and simulations. And I'd much rather see you argue with a simulation than with my analysis.
So look below. I've taken your model (R? = 0) and two variations thereof (R? = 13987 and R? = infinity) and simulated the conditions of the bench test you published in your article. The results are identical to one another and in accord with those of your test. There is nothing "wrong" with any of them.
Your choice of R? = 0 is completely arbitrary. Any value from zero to infinity works. Zpg and Zkg are determined in part by R?. This means that they are not determined by your model or by any tests in your article. The article presents no evidence that they equal 1/gm.
I’m guessing that you were surprised to discover that there is indeed a plethora of models with the same topology as yours which gets the voltages and time constant of a balanced Cathodyne right, but is hopelessly self-contradictory when it comes to the plate and cathode to ground impedances Zpg and Zkg.
Perhaps you’ll claim that your model best represents how a Cathodyne really works. If so, please consider this. Even a cursory examination of a triode reveals that its only paths to ground are indirect and through the P and K terminals – there is no hidden ground lurking within a triode. And the simulations and the bench test have proven that any short to ground is completely non-functional, and cannot be part of “how a Cathodyne really works”. If any model is “best”, it is probably Burkhart Vogels’s, which has no path to ground. But I don’t think either one of us would use his model to determine Zpg or Zpk.
I believe it is time to stipulate that these models are useless for determining Zpg and Zkg. Don’t you agree?
Perhaps you’ll claim that your model best represents how a Cathodyne really works. If so, please consider this. Even a cursory examination of a triode reveals that its only paths to ground are indirect and through the P and K terminals – there is no hidden ground lurking within a triode. And the simulations and the bench test have proven that any short to ground is completely non-functional, and cannot be part of “how a Cathodyne really works”. If any model is “best”, it is probably Burkhart Vogels’s, which has no path to ground. But I don’t think either one of us would use his model to determine Zpg or Zpk.
I believe it is time to stipulate that these models are useless for determining Zpg and Zkg. Don’t you agree?
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