I picked up some VCR2N FETs a while back, and with the discussion of FETs as gain control elements in these parts recently, it seems like a good time to mess around with them.
I "borrowed" Fred's opto sidechain and modified it to work with FETs -
It puts out two control voltages. CV1 is suitable for using with the FET as a series element in an L-pad arrangement or an opamp feedback-loop shunt type of doohickey. It should also work as a meter output.
CV2 is for using the FET as the shunt element in an L-pad, like in the 1176.
I put one together on a RatShak board, and testing with fingertip signal injection indicates that, amazingly, it does what it's supposed to.
So now I can start messing around in earnest. I'm especially curious to see what happens when you use one FET as a series element and another as a shunt element in an L-pad. Hope someone finds this useful.
I "borrowed" Fred's opto sidechain and modified it to work with FETs -
It puts out two control voltages. CV1 is suitable for using with the FET as a series element in an L-pad arrangement or an opamp feedback-loop shunt type of doohickey. It should also work as a meter output.
CV2 is for using the FET as the shunt element in an L-pad, like in the 1176.
I put one together on a RatShak board, and testing with fingertip signal injection indicates that, amazingly, it does what it's supposed to.
So now I can start messing around in earnest. I'm especially curious to see what happens when you use one FET as a series element and another as a shunt element in an L-pad. Hope someone finds this useful.