Hi a few questions, Does your "cave" have any connectivity to the outside world ?
Are there any places your cave has connectivity to that might have enough of a sky view to provide periodic gps coverage ? Do you need a COTS (commercial off the shelf) solution or can you accept something that has been kludged together ? Do you need a Peng or other professional to sign off on the solution ? (In my experience PTP may on occasion be found in industrial settings where a Peng may be required to sign off on the solution.) Mark Spencer On 2015-05-12, at 4:00 PM, "Tucek, Joseph" <[email protected]> wrote: > I'm looking for information on non-GPS time sources. > > For background, I need to provide PTP to a cluster where we don't have line > of sight to the sky, and are unlikely to get roof-rights without a fight. > There are CDMA solutions that would work (e.g. Endrun Technologies), but I > was wondering if there were any other options. I either need an indoor > capable PTP, or an indoor capable PPS. Microsemi claims to have an indoor > capable "GNSS" system, but I've yet to find a sales rep to talk about it; if > anyone has a link to one who can, I'd love to find out the problems^W^W^W^W > talk to them about it. > > For an example of something that almost but doesn't quite work, Beagle > Software has a CDMA NTP server, but they do neither PTP nor PPS in the CDMA > version. Similarly, Meinberg will sell a PTP unit that freeruns (if you > override the config), but they have no solution to discipline via CDMA. > > I'm also curious if anyone has any idea about non-GPS time sync after CDMA > gets turned off (can I get time from 4G?). > > My endgame worst case is to just do PPS from a stratum 2 NTP (or even a > freerunning oscillator) and lie to my PTP server; hard sync to UTC is a > secondary concern so long as the cluster agrees with itself. Endrun is > looking pretty good, but I'd really like to have a second option to compare > against. > > -Joe > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
