Symmetricom makes GPS based NTP time servers with excellent holdover capability. I think our "SyncServer" with an OXCO is good for +/- 0.5 second holdover over something like 60 days. They have options for Rb oscillators installed that will make that much much better and it might fall inside of your requirements. Give them a look. You're welcome to mail me directly with questions about mine if you like.
-Bob On Thu, Sep 9, 2010 at 9:37 AM, Ralph Smith <ra...@ralphsmith.org> wrote: > We have a requirement for approximately ten radio sites to be synchronized > to within 30 ns of each other. Ordinarily you could throw in an > appropriate GPSDO and be done with it. However, we also have the > reqirement to be able to operate independent of GPS for up to six days. If > we were able to have each site within line of sight of another, and could > form a network including all sites, we could do differential time > measurement between the mutually visible sites and correct in that way. > Unfortunately, that is not the case. Absolute time accuracy is not > critical, but relative time accuracy is. Does anyone out there have any > ideas? > > Thanks, > Ralph > AB4RS > > _______________________________________________ > 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.