Hi For most OCXO’s most certainly not. The typical OCXO improves on ADEV as it runs. That said, a good OCXO should have a 1 second ADEV of at least parts in 10^-12 rather than 10^-11. A 5370 should have a floor at 1 second of around 2x10^-11. You may be measuring your counter doing something stupid ( = needs alignment) rather than the OCXO or Cs.
Bob > On Jun 27, 2016, at 5:55 PM, Bob Stewart <b...@evoria.net> wrote: > > I've had a specific GPSDO running for some time now, and I notice that the > noise at tau 1s has gotten worse as the retrace flattens out. In this case, > the ADEV was about 3.6E-11 a month or so ago, and has now gone up to about > 8.5E-11. (Measurements performed by a 5370A against a PRS-45A Cs standard.) > Is this normal as the startup drift settles out? It's been on the same power > supply module during this time, but I have been using it to test new code, so > the DAC has been cycled from midpoint to lock numerous times. Another unit > that's been running for some time has done essentially the same thing. > Weather? Environment? GPS demons? > > Bob - AE6RV > ----------------------------------------------------------------------------------- > GFS GPSDO list: > groups.yahoo.com/neo/groups/GFS-GPSDOs/info > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
