Schematics / DJB-004 Module-Mixer Full Wave Rectifier Amp Comparator
DJB-004 Module - Mixer / Full Wave Rectifier / & Comparator by Dave Brown , the page dedicated to this Module is here http://modularsynthesis.com/modules/DJB-004/djb004.htm ,from the notes there :
This module was inspired by Richard Brewster's Mixer-Comparator module. I decided I wanted additional functionality and added a Full Wave Rectifier as an alternate output. A jumper strap on the PCB selects either AC or DC coupling for the full wave rectifier. For AC coupling the gain is x2 so the output is a full +/- 5 volts.