Have you a BVA? If you have a BVA then it is the best source for PN measurements and, if disciplined, for AD measurements too. Anyway, for AD I think that every GPSDOs can do (TBolt preferred).
On Fri, Sep 28, 2012 at 11:15 AM, Bruce Griffiths < bruce.griffi...@xtra.co.nz> wrote: > Ulrich Bangert wrote: > >> Gentlemen, >> >> I know that lots of you own a GPSDO, some of you two or even more. For >> that >> reason I conclude that there must be a lot of knowledge available on how >> different GPSDOs perform against each other. This is why I want to put >> forward the question for the BEST GPSDO in terms of >> >> a) phase noise up to 100 kHz from the carrier >> >> b) AD for tau> 0.1 s and< say 7200 s (where the AD is controlled by LO >> AND >> GPS and not by GPS alone) >> >> The basic question is: If we want a reference that can be used for phase >> noise measurements as well as for AD measurements, what shall we buy? If >> you >> come to the opinion that a) and b) cannot be satisfied by the same device, >> then suggest different devices that you would use for a) and b). >> >> My personal guess is (without owning one) that a Z3815 may be a candidate >> due to its E1938 oscillator. >> > The phase noise floor of the E1938 isnt all that low and there is an > "interesting bump" in the region above a few kHz offset. > If you want I can send you the data obtained using a Timepod with dual > reference sources. > The Z3815 PN floor should be somewhat higher due to its relatively low > output signal level. > The spurs due to the internal switching regulators may also be interesting. > > But as to be seen on Tom's pages there are >> better and worse specimen of this OCXO too. My own measurements with the >> new >> Timepod indicate that my Z3805 with the MTI260 OCXO can't be that bad. You >> may even have luck with a double oven HP10811 in a Z3801 although the 6 >> channel gps receiver is surely not state of the art. Perhaps the >> Thunderbolt >> is the solution? >> >> > The thunderbolt phase noise floor isn't stellar due principally to the > noisy output buffer amp. > However the PN floor of the OCXO used in some Thunderbolts can be quite > low. > > I will be glad to read what you judge! >> >> Ulrich Bangert >> www.ulrich-bangert.de >> Ortholzer Weg 1 >> 27243 Gross Ippener >> >> >> ______________________________**_________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/** >> mailman/listinfo/time-nuts<https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts> >> and follow the instructions there. >> >> >> > Bruce > > > ______________________________**_________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/** > mailman/listinfo/time-nuts<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.