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Wow, what a fantastic app!

But it still has a few glitches.

Here's a real simple circuit, which should just show a straight input-output relationship, but it bobbles all over the place on a DC sweep:

It also oscillates on a time-domain look-see. But it shouldn't. It still oscillates if you hang 1uF capacitors on base and collector. Impossible.

I know it's hard to get all those equations to solve, but really, this simple a circuit shouldn't blow up so spectacularly!

Never mind!

I thought since the device sim spec says that avalanche phenom wasn't simulated, I could push any voltage into the transistor.

But not quite--I figured out if you bump up the "Early voltage" in the device definition, the wobblyness goes away.

It would be nice if the device list included a high-voltage transistor.

I took a look and this was, in fact, a convergence problem related to the Early effect. The issue should now be fixed -- please try your DC sweep now, and it should look fine. (The documentation is still correct -- junction breakdown is not modeled in BJTs.)

Oh, hurray! Now I can proceed with modelling a 6J5 tube. Cheers,