Could you guys check this cascode article for me

[aletheian]

I'm really pissed now that I forgot to change that paragraph... now I have to do the math for the whole thing over again.

[cerrem]

As long as the cathode resistor is bypassed..then the RED line is the slope representing 1/gm of the top valve.....
I have the gm curves for a 6922 ...but not with me... There is a book that has them...maybe someone here can help with that..
As for active feedback.....I am refering to using an inverting op-am in the feeback loop between the lower anode and the upper tubes grid...while still maintaining the DC reference voltage...

Chris

[aletheian]

Originally posted by cerrem
As long as the cathode resistor is bypassed..then the RED line is the slope representing 1/gm of the top valve.....
I have the gm curves for a 6922 ...but not with me... There is a book that has them...maybe someone here can help with that..
As for active feedback.....I am refering to using an inverting op-am in the feeback loop between the lower anode and the upper tubes grid...while still maintaining the DC reference voltage...

Chris

INVERTING OPAMP! Brilliant. I would never have thought of that.
1/gm for the slope eh? I guess for a rule of thumb, I could use a straight line since 1/12,500 is off the chart anyway.
I think what I need to do is invest in a book of complete tube curves. Last night I actually found a 36 page PDF from Phillips that has all the curves I need, INCLUDING a graph for a 6922 in cascode... boy would that have made life easier