[quote author="Learner"]
Thanks for the link.
I have seen these, but that's a set of specialized programs, not compatible with Spice, is it?
JH.
Yea, I they are an independent program that assist you to design/calculate the biasing value and predict the outcome. However, I don't think it will display transient analysis..... :sad:
I donno why no Pspice program allows you to customise your own active device models by inputing the data sheet parameters and curves... :shock:
Or is there!? :?:[/quote]
I think PSpice has such features for diodes, not sure about transistors, certainly not for tubes.
A quick check of the 12AX7 and 12BH7 models from the duncanamps site shows their severe limitations. Very simple modeling, lower part of plate courves just cut off ...
Ok to find bias points, at least in the quick circuit I've tried.
No way to find a sweet spot for certain distortion behaviour, though ...
I found a much "better" model for the 12AX7 (must look up the link), plate courves look really nice, but it has tremendous problems with convergence. So I could plot the data sheet courves easily, but a simple grounded cathode amp with bypassed Rk already runs into errors ...
Sigh.
JH.