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Re: keep going...sooner or later, you'll get it.

Doug wrote:

::::Also NC was not *ALL* wrong, and you have yet to respond to this instance where his own text contradicts your interpretation of the whole. So please quit saying that NC says a-a/4,...::::

Well, you have to do all the math correctly first... and know what the values on the graphs mean and if they represent the values of one tube or two tubes and etc...

Norman apparently anticipated your confusion, and stated;

"All this may seem a little confusing at first, but the important point to realize is that the practical circuit makes the two loads appear to be in series., because the widings of the transformer which combine the output are in series. But the magnetizing effect in the transformer is differential, so you subtract the smaller current from the larger."

"This means that the current change represented on the curves is double that which occurs in each half-winding, and the voltage difference on the curves is what occurs across one half of the winding (either half). Hence, the effective impedance considered on the load line is 1/4 of the impedance from plate to plate."

To get the correct answers you must use the right math and the right values for each of the parameters..

Now, if you would be kind enough to show me where (in his text) Norman states explicitly (please quote him directly) that the load seen by each tube is raa/2 I would be most appreciative. Your pulling raw numbers off of the graphs without understanding the formulas, relationships, and values of the parameters. And this, as Norman predicted, will lead to confusion on your part.


next... your cry about


"....conservation of energy for class A operating conditions."

So you think that Steve Bench, John Broskie, RCA engineers, Termin, Crowhurst, etc, et al... all have violated this dictum?

but... first we would need to know how power is developed in each half of the primary and then ascertain how that power is then "combined" in the output (see Norman's text above)...

if the two primary half windings are in series then surely the value of each half cannot be raa/2. If you have a 5K reflected impedance on either side of ct... then the combined impedance from end to end will be 20K not 10K.

Plus we know that if the reflected impedance of the whole primary is (n1/n2)^2 times the load on the secondary... then... each half primary will have just one quarter the imepedance of the whole which follows mathmetically from ((n1/2)\n2)^2) times the load on the secondary.

If you double the turns you quadruple the impedance. And this axiom is not and cannot be violated.

Transformed series impedances do not add like resistors. Just as two eight ohm windings in series with each other combines or adds up to 32 ohms not 16 ohms.

so your thesis (raa/2) would also violate the "conservation of energy" theorem.... you would have less power than is generated by the tubes by half when two 5K series connected windings are shown to have an end to end impedance of 20K and not the 10K as you have proposed.


MSL



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