This question might be too localized, but I try.
Is it possible to replace a variable resistor by a MOSFET, under conditions shown in the following schematic?
If yes, can someone propose a MOSFET type or the required MOSFET parameters.
What I am actually trying to accomplish is to replace R2a by something simple that I can control with a microcontroller (DAC).
I am hacking an existing device and can not replace the resistor R1.