Thanks to Scott J. for pointing it out - The Rate potentiometer was missing in the wiring diagram. I have added it now. (Doesn't change anything on the PCB, but may be important to those who are creating a panel layout for this.) http://www.jhaible.de/sonofstormtide/sost_sch7.pdf http://www.jhaible.de/sonofstormtide/sonofstormtide.html JH.