The chinese GPSDO's famous on E-bay are not really phase locked to begin with, they are only frequency locked and often with a small frequency offset. I don't think any of your questions apply to this kind of unit. See e.g. http://www.ke5fx.com/gpscomp.htm
Units that have been spec'ed for holdover in terms of time delta, make phase the number one priority and will gladly "oversteer" frequency to get the phase to match back up after holdover and then settling down again,. e.g. http://leapsecond.com/pages/z3801a-efc/ In recovery from a holdover where something went clearly wrong - the holdover specs of the unit were greatly exceeded - they declare themselves unlocked, and will do a phase jump and enter a "frequency lock" mode until oscillator parameters are relearned and they again declare themselves locked. Tim N3QE On Sun, Apr 3, 2016 at 11:39 PM, Hal Murray <hmur...@megapathdsl.net> wrote: > > Has anybody studied what happens when a GPSDO comes out of holdover? Has > anybody seen any specs? I don't think I have. > > I think you have a choice of quick recovery for time or frequency, but you > can't get both. > > Suppose your setup has been in holdover for a while. The frequency is > slightly off. The time offset of the PPS pulse will be the integral of the > frequency offset. > > What happens when you come out of holdover? If you fix the frequency, the > PPS will stay off. > > Suppose the PPS has drifted by 1 ns. If you correct that in 1 second, the > frequency will need to be off by 1E9 during that second. > > > -- > These are my opinions. I hate spam. > > > > _______________________________________________ > 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.