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.