Using a latching relay driver for true bypass 12th June 2010
A nice alternative to Millenium Bypass and expensive sometimes unreliable 3PDT footswitches. This works with normally open momentary contact switches, of which there is a massive range of styles, and best of all there's no audible click when switching.
The schematic by RG Keen at Geofex:
My working prototype (doesn't exactly match the updated layout above!)
Click here to download the PCB trace.