If you want to make your own models, you need to read up on the Koren tube spice model, on his webpage, all the parameters are explained. BTW, all the parameters shown above are unit-less.
Wow.
I did read it.
No way I can do that.....
So I hope someone will put in the 100TH curves.
Thanks
Nonlinerar distortion are calculeted directly from the characteristics of the selected tube. Algorithm is based on geometrical rules. Here is the link to used formulas:
Program wspomagający dobor punktu pracy triody
You have to use google translator (sorry for this inconvenience) or analyze only the formulas and chart.
These formulas are approximate, but were commonly used by designers in the gold era of electron tubes.
BTW. Take into account that the harmonic components strongly depends on the selected operating point.
I've noticed something interesting when using this simulator looking for triodes for small signal amplification and for long tail pair drivers. Some types (12ax7, 6sn7) have fairly low distortion, decaying moderate 2nd to fairly low 3rd, whether biased at around a volt or two or center biased. Other types (12at7, 12au7, 12bh7) are generally higher distortion, but have a 3rd harmonic null around center bias. Is this a real effect? Any ideas as to the cause if so?
Actually I don't think so. It may be simple if you have done it manually before. It would be helpful to have some guidelines on where to start (B+, current), what to watch for such as distortion components, max dissipation, how to use the output (plate, cathode resistors) etc... I'd never designed anything before and it was a long time before I understood what I was looking at. It was just a chart with a lot of moving lines. I had an 'AHA' moment and finally got it.
Don't get me wrong, I'm not criticizing the tool itself, it is actually great once you understand how to use it.
Don't get me wrong, I'm not criticizing the tool itself, it is actually great once you understand how to use it.
