Very nice. Thanks! (I'll report when I have my holdover experiment finished in a few days.)
John ---- Tom Van Baak said the following on 01/25/2008 05:34 PM: >> Tom's plots at http://www.leapsecond.com/pages/z3801a-osc/ show 13 >> Z3801As running in unlocked mode, measured against one of his most >> excellent references. So I think that plot shows what you're looking >> for. I was just trying to show what you get when you are running in the >> normal locked condition (my units almost never go into holdover, so I >> was more interested in what the normal behavior was). >> >> One thing that's not clear from Tom's page, though, is whether the units >> were in "smart" holdover mode (ie, no GPS signal but the CPU still >> steering based on its learned aging curve) or truly freestanding with no >> EFC being applied. > > John, > > I'm pretty sure those Z3801A were in factory reset mode when > I made the stability measurements. For that experiment I was > only interested in short-term stability; a range of tau where the > smart ageing correction has little or no effect. > > You also asked about z3801a free-run vs. GPS locked plots. I > found old data for GPSDO #4 (of the 13 I tested in 2002). > > Free-run stability for #4. > http://www.leapsecond.com/pages/z3801a-osc/log8007v.gif > > GPS locked stability for #4: > http://www.leapsecond.com/museum/z3801a/log8286v.gif > > Here I put the two runs in color on the same plot: > http://www.leapsecond.com/museum/z3801a/z3801a-free-lock.gif > > Between the three plots you get a good feel for the function > of a GPSDO. > > /tvb > > > _______________________________________________ > 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.
