original and ingenious circuits ... (was: in How the heck does th e MS-50 filter WORK?)

[Martin Czech]

> So, if you like this topic, write what were important circuit discoveries
> for you !
> 
I don't know if Serge Tchernepin actually used Norton-OpAmps in his
designs, but he has severall patents about these current mirror input
stage designs.  It was quite interesting to see how voltage controlled
impedance and thus voltage controlled phasers/filters etc. can be
realized. Also wave-shapers, rectifiers and current integrators (which
can also be found on the LM3900 data sheet).

m.c.