There is simply no experimental evidence to support the claim that Zpg = Zkg = 1/gm.
As long as the loads are equal, ALL of the experimental evidence is consistent with that. I haven't found an exception and, based on your one experiment, neither have you.
Of course it's consistent. But only in the sense that it is not contradictory. Heater voltages of 6.3V are consistent with B+ voltages of 300V. That doesn't mean either one predicts or constrains the other. "Consistent" doesn't mean "implies".
There is not a single test for the Zpg or Zkg of a balanced Cdyne that you can point to that favors the value of 1/gm above any other. 143,738 is no more or less valid than 1/gm.
There is no way to bench test Zkg or Zpg if the Cdyne is kept balanced. There’s no voltage at the junction of the sources in the model whether its center is grounded or floating. There’s no voltage at the junction of the coupling caps on the bench. There’s no current from either of these points to ground. Ergo, you can’t measure the impedance connecting these points to ground. And because that impedance is a part of Zp and Zk, these tests can say nothing about them.
Why don't you engage with the argument in the above paragragh whose conclusion you deny, and try to find flaws in it? Ignoring reasoning is no defense against its conclusion.
There is not a single test for the Zpg or Zkg of a balanced Cdyne that you can point to that favors the value of 1/gm above any other. 143,738 is no more or less valid than 1/gm.
There is no way to bench test Zkg or Zpg if the Cdyne is kept balanced. There’s no voltage at the junction of the sources in the model whether its center is grounded or floating. There’s no voltage at the junction of the coupling caps on the bench. There’s no current from either of these points to ground. Ergo, you can’t measure the impedance connecting these points to ground. And because that impedance is a part of Zp and Zk, these tests can say nothing about them.
Why don't you engage with the argument in the above paragragh whose conclusion you deny, and try to find flaws in it? Ignoring reasoning is no defense against its conclusion.
There is not a single test for the Zpg or Zkg of a balanced Cdyne that you can point to that favors the value of 1/gm above any other. 143,738 is no more or less valid than 1/gm.
Other than all of the actual experimental data. Plug 143,738 ohms into the Thevenin source impedance at either or both outputs and you get the wrong answer.
Of course it's consistent. But only in the sense that it is not contradictory. Heater voltages of 6.3V are consistent with B+ voltages of 300V. That doesn't mean either one predicts or constrains the other. "Consistent" doesn't mean "implies".
That might be the most singularly inapt analogy I've ever seen. The Zout = 1/gm model correctly predicts the effects of loading. 6.3V on the heater predicts nothing about the plate. Or was that just a silly debating trick?
And once again, you simply ignore rather than confront an inconvenient argument. You refuse to engage or acknowledge what doesn't suit you.
You will forgive me if I wonder if you are trying to misread what I have said. The fact is that all of the following models are consistent with all of your experimental data. That means that your experiments are incapable of determining which, if any, is correct. Which means you aren't measuring Zpg or Zkg.

You will forgive me if I wonder if you are trying to misread what I have said. The fact is that all of the following models are consistent with all of your experimental data. That means that your experiments are incapable of determining which, if any, is correct. Which means you aren't measuring Zpg or Zkg.

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By the way, if you eliminate your added Dunsel resistor entirely, you end up with the Figure 2 in my article.
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As long as the loads are equal, ALL of the experimental evidence is consistent with that. I haven't found an exception and, based on your one experiment, neither have you.
Even when identical loads behave non-equal ( due to being on
different push or pull parts of a forward conducting curve ).
Even push the example to extremes of A2 stOOpidity and open
any GNF feedback loops that might push it back into balance.
There just isn't a whole lot damage done by impedance being
locally unequal, when compared to locally forced equal. Its
proven to my satisfaction that there was nothing wrong with
the old unequal impedance Cathodyne that wants fixing.
The worst bent case (aside from DC) has been explored, and
this debate will find no answers at the end of that tunnel.
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Those models are incorrect. You might want to squint at them and correct.
If you add a resistor that has no function in the circuit (assuming a correct circuit, not the ones you drew), then a measurement under the stated constraints will indeed show no difference.
If you add a resistor that has no function in the circuit (assuming a correct circuit, not the ones you drew), then a measurement under the stated constraints will indeed show no difference.
We agree that the "resistor has no function in the circuit" and "a measurement under the stated constraints will indeed show no difference."
That's what I call progress! Now let's examine the consequence of that admission.
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?
That's what I call progress! Now let's examine the consequence of that admission.
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?
The way you present them, they're trivially easy to distinguish. Take a close look and do some analysis. 😀
The answer which is not an answer. 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?
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?
I didn't say anything about it, it's your nonfunctional part. Except in the circuits you just drew, where it's extremely functional and easy to measure, in a bad way.
Of course you've said something about it. You've said that the model it is in is wrong. And within the constraints of balanced Cdyne measurements, 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?
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?
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That is not an answer. Why can't you answer a simple question?
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?
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?
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Your circuit doesn't represent a cathodyne, so you might want to take a second look at it.
I won't bother saying that again.
I won't bother saying that again.
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