seen their GPSDO's, Pendulums, etc jump after long times like this, sometimes after weeks of perfect operation. bye, Said In a message dated 10/24/2008 06:29:34 Pacific Daylight Time, iovane@ inwind.it writes: > See the following plot, blue is phase offset to UTC, brown is EFC voltage. Said, please, what is on the X axis? When did this jump occur? Thanks, Antonio I8IOV