Hi I’m sure they expect you to take out the sawtooth error before you do the comparison. Are you doing that?
Bob On Sep 13, 2014, at 6:41 PM, Peter Reilley <pe...@reilley.com> wrote: > I see in the Trimble Resolution T data sheet that they > say that the PPS signal is "within 15 nS to GPS or UTC (1 Sigma) > when using an over determined solution in stationary mode.". > I take this to mean that the PPS signal should be within 15 nS > and that comparing 2 units that there should be no more than > 30 nS between the two edges. This is comparing the rising edges. > > > Pete. > > > -----Original Message----- > From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp > Sent: Saturday, September 13, 2014 6:26 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Correcting jitter on the 1 PPS signal from a > GPSreceiver. > > Hi > > Where are you getting the "15 ns accuracy" number from? When I look at the > Trimble spec's they have a number of errors described (like sawtooth) that > are larger than 15 ns. > > Bob > > On Sep 13, 2014, at 10:41 AM, Peter Reilley <pe...@reilley.com> wrote: > >> I have 2 Trimble Resolution T receivers and I have compared the 1 PPS > signal >> between the 2 units. They are spec'ed at 15 nS accuracy. I am seeing >> about >> 80 nS of jitter between the two. This is with about 6 satellites in > view. >> >> I was thinking about ways to improve this. Since this is a stationary >> installation, >> can you use the jitter in the reported location (latitude and >> longitude) to correct for the 1 PPS jitter? >> >> The location data is derived using the internal GPS disciplined >> oscillator so both >> pieces of information should show the same jitter error. If you compare >> the reported >> location with the known fixed location you should be able to use that >> error to correct for the 1 PPS error. >> >> Does this make sense or am I missing something? >> >> Pete. >> >> >> _______________________________________________ >> 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. > > _______________________________________________ > 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.
