Maybe you can remind us what U7 is. Someplace I have a schematic but not handy right now. On Sun, May 13, 2012 at 5:24 AM, Kevin Staley <kevin.staley at virgin.net> wrote: > Hi All > > I am building the Brooke Shera GPSDO controller board but have run into > problems sourcing U7. Chris Albertson Redondo Beach, California