V G wrote:
> I'm not understanding this. Right now, the opamp output drives a
> *negative* feedback control. The higher the opamp output, the lower
> the input to the Darlington pair. If I connect the opamp output to
> the base of the Darlington pair, wouldn't the be a *positive*
> feedback control?

Right, which is why you have to reverse the opamp inputs.

Once again, ditch, V1, R4, Q3, and R5.  Connect the opamp output directly t=
o
the base of Q2, but the sign of the feedback now needs to be flipped.


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