onepole.sch This is a differential pair with current mirror load feeding the output current into an integrating capacitor C2. The output is fed back to the inverting input, reducting that input transitor to a diode D1. This feedback makes the drive current dependent on the voltage over C2. Main purpose is for envelope generation. I which case we do need some form of offset compensation such that the off state is zero current/voltage. Questions: * Can the diodes D1 / D2 be implemented as 1N4148 or do they need to be transistors with base-collector connection, matched to respective Q1 / Q2? The result should just be offset voltage.