Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly
> I've not been following this discussion too closely, but were the nav > solutions from the GPS steady and continuous during the event (that is, > was just a time discontinuity). I'm guessing that since the problem was > only in the "how to convert from GPS to UTC" parameters that the nav > solution was steady. Jim, Nav solutions were fine. Time solutions were fine. It was just a UTC offset problem (and then only for some receivers). > And this brings up an interesting question. On receivers that provide a > 1pps, do they bring out the 1pps on GPS time or on UTC time. I suspect > some are GPS and some are UTC. Almost all timing receivers allow you to choose between GPS time and UTC. It's in the manual. The TBolt and Z38xx-series and 58503-series make it really easy to switch from one to the other. /tvb ___ 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.
Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly
On 1/27/16 11:46 PM, Magnus Danielson wrote: Fellow time-nuts, Here is the official statement. Cheers, Magnus I know we're all time-nuts here and not position-nuts. The thing in the statement that was intriguing was about GPS guided munitions. 13.7 microseconds is about 4.5 km. I've not been following this discussion too closely, but were the nav solutions from the GPS steady and continuous during the event (that is, was just a time discontinuity). I'm guessing that since the problem was only in the "how to convert from GPS to UTC" parameters that the nav solution was steady. And this brings up an interesting question. On receivers that provide a 1pps, do they bring out the 1pps on GPS time or on UTC time. I suspect some are GPS and some are UTC. And, did this "ripple in the force" cause all those NTP synchronized clocks to hiccup (if a NTP ticker is UTC driven vs GPS driven) Forwarded Message Subject: CGSIC: FW: Official Press Release - GPS Ground System Anomaly Date: Thu, 28 Jan 2016 01:13:13 + From: Civil Global Positioning System Service Interface Committee (CGSIC)Reply-To: cg...@cgls.uscg.mil To: cg...@cgls.uscg.mil All CGSIC: Air Force Official Press Release - GPS Ground System Anomaly On 26 January at 12:49 a.m. MST, the 2nd Space Operations Squadron at the 50th Space Wing, Schriever Air Force Base, Colo., verified users were experiencing GPS timing issues. Further investigation revealed an issue in the Global Positioning System ground software which only affected the time on legacy L-band signals. This change occurred when the oldest vehicle, SVN 23, was removed from the constellation. While the core navigation systems were working normally, the coordinated universal time timing signal was off by 13 microseconds which exceeded the design specifications. The issue was resolved at 6:10 a.m. MST, however global users may have experienced GPS timing issues for several hours. U.S. Strategic Command's Commercial Integration Cell, operating out of the Joint Space Operations Center, effectively served as the portal to determine the scope of commercial user impacts. Additionally, the Joint Space Operations Center at Vandenberg AFB has not received any reports of issues with GPS-aided munitions, and has determined that the timing error is not attributable to any type of outside interference such as jamming or spoofing. Operator procedures were modified to preclude a repeat of this issue until the ground system software is corrected, and the 50th Space Wing will conduct an Operational Review Board to review procedures and impacts on users. Commercial and Civil users who experienced impacts can contact the U.S. Coast Guard Navigation Center at (703) 313-5900. V/R Rick Hamilton CGSIC Executive Secretariat GPS Information Analysis Team Lead U.S. Coast Guard Navigation Center 703-313-5930 ___ 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.
Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly
Jim, On 01/28/2016 01:22 PM, jimlux wrote: On 1/27/16 11:46 PM, Magnus Danielson wrote: Fellow time-nuts, Here is the official statement. Cheers, Magnus I know we're all time-nuts here and not position-nuts. The thing in the statement that was intriguing was about GPS guided munitions. 13.7 microseconds is about 4.5 km. I've not been following this discussion too closely, but were the nav solutions from the GPS steady and continuous during the event (that is, was just a time discontinuity). I'm guessing that since the problem was only in the "how to convert from GPS to UTC" parameters that the nav solution was steady. That is exactly what Meinbergs research as presented by Martin shows. In particular, it's the A0 coefficient of the GPS to UTC conversion message which is out of tune. And this brings up an interesting question. On receivers that provide a 1pps, do they bring out the 1pps on GPS time or on UTC time. I suspect some are GPS and some are UTC. You can configure, most of them would default to UTC and in my experience, many systems wants UTC. And, did this "ripple in the force" cause all those NTP synchronized clocks to hiccup (if a NTP ticker is UTC driven vs GPS driven) NTP bumping around 13,7 us... I'm not sure I *really* care for most usage. Oh... not to speak about telecom and broadcast networks. When national TV broadcast networks suffers greatly, we start to care about these things. *GREATLY* Cheers, Magnus Forwarded Message Subject: CGSIC: FW: Official Press Release - GPS Ground System Anomaly Date: Thu, 28 Jan 2016 01:13:13 + From: Civil Global Positioning System Service Interface Committee (CGSIC)Reply-To: cg...@cgls.uscg.mil To: cg...@cgls.uscg.mil All CGSIC: Air Force Official Press Release - GPS Ground System Anomaly On 26 January at 12:49 a.m. MST, the 2nd Space Operations Squadron at the 50th Space Wing, Schriever Air Force Base, Colo., verified users were experiencing GPS timing issues. Further investigation revealed an issue in the Global Positioning System ground software which only affected the time on legacy L-band signals. This change occurred when the oldest vehicle, SVN 23, was removed from the constellation. While the core navigation systems were working normally, the coordinated universal time timing signal was off by 13 microseconds which exceeded the design specifications. The issue was resolved at 6:10 a.m. MST, however global users may have experienced GPS timing issues for several hours. U.S. Strategic Command's Commercial Integration Cell, operating out of the Joint Space Operations Center, effectively served as the portal to determine the scope of commercial user impacts. Additionally, the Joint Space Operations Center at Vandenberg AFB has not received any reports of issues with GPS-aided munitions, and has determined that the timing error is not attributable to any type of outside interference such as jamming or spoofing. Operator procedures were modified to preclude a repeat of this issue until the ground system software is corrected, and the 50th Space Wing will conduct an Operational Review Board to review procedures and impacts on users. Commercial and Civil users who experienced impacts can contact the U.S. Coast Guard Navigation Center at (703) 313-5900. V/R Rick Hamilton CGSIC Executive Secretariat GPS Information Analysis Team Lead U.S. Coast Guard Navigation Center 703-313-5930 ___ 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.
Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly
Tom, On 01/28/2016 04:58 PM, Tom Van Baak wrote: I've not been following this discussion too closely, but were the nav solutions from the GPS steady and continuous during the event (that is, was just a time discontinuity). I'm guessing that since the problem was only in the "how to convert from GPS to UTC" parameters that the nav solution was steady. Jim, Nav solutions were fine. Time solutions were fine. It was just a UTC offset problem (and then only for some receivers). Quite a lot of receivers it turns out. The way it works, many receivers could go lucky through the events. And this brings up an interesting question. On receivers that provide a 1pps, do they bring out the 1pps on GPS time or on UTC time. I suspect some are GPS and some are UTC. Almost all timing receivers allow you to choose between GPS time and UTC. It's in the manual. The TBolt and Z38xx-series and 58503-series make it really easy to switch from one to the other. I find that most use in telecom and broadcast is to set them for UTC. Cheers, Magnus ___ 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.
Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly
Poul-Henning, On 01/28/2016 11:27 PM, Poul-Henning Kamp wrote: In message <56aa6aa2.6050...@rubidium.dyndns.org>, Magnus Danielson writes: And, did this "ripple in the force" cause all those NTP synchronized clocks to hiccup (if a NTP ticker is UTC driven vs GPS driven) NTP bumping around 13,7 us... I'm not sure I *really* care for most usage. I don't think most NTPD based servers would even notice the pattern I saw on my receivers. Indeed. Even if they saw it, as soon as you got past the first router that bump is nothing anyways. I just *might* have been using a bit of an understatement. Cheers, Magnus ___ 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.
Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly
In message <56aa6aa2.6050...@rubidium.dyndns.org>, Magnus Danielson writes: >> And, did this "ripple in the force" cause all those NTP synchronized >> clocks to hiccup (if a NTP ticker is UTC driven vs GPS driven) > >NTP bumping around 13,7 us... I'm not sure I *really* care for most usage. I don't think most NTPD based servers would even notice the pattern I saw on my receivers. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ 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.
Re: [time-nuts] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly
What was interesting was in addition to the bump was that the Garmin nav receiver in the car was unable to get a fix until it did a full cold start Content by Scott Typos by Siri > On Jan 28, 2016, at 5:37 PM, Magnus Danielson> wrote: > > Poul-Henning, > >> On 01/28/2016 11:27 PM, Poul-Henning Kamp wrote: >> >> In message <56aa6aa2.6050...@rubidium.dyndns.org>, Magnus Danielson writes: >> And, did this "ripple in the force" cause all those NTP synchronized clocks to hiccup (if a NTP ticker is UTC driven vs GPS driven) >>> >>> NTP bumping around 13,7 us... I'm not sure I *really* care for most usage. >> >> I don't think most NTPD based servers would even notice the pattern I >> saw on my receivers. > > Indeed. Even if they saw it, as soon as you got past the first router that > bump is nothing anyways. > > I just *might* have been using a bit of an understatement. > > Cheers, > Magnus > ___ > 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] Fwd: CGSIC: FW: Official Press Release - GPS Ground System Anomaly
Fellow time-nuts, Here is the official statement. Cheers, Magnus Forwarded Message Subject: CGSIC: FW: Official Press Release - GPS Ground System Anomaly Date: Thu, 28 Jan 2016 01:13:13 + From: Civil Global Positioning System Service Interface Committee (CGSIC)Reply-To: cg...@cgls.uscg.mil To: cg...@cgls.uscg.mil All CGSIC: Air Force Official Press Release - GPS Ground System Anomaly On 26 January at 12:49 a.m. MST, the 2nd Space Operations Squadron at the 50th Space Wing, Schriever Air Force Base, Colo., verified users were experiencing GPS timing issues. Further investigation revealed an issue in the Global Positioning System ground software which only affected the time on legacy L-band signals. This change occurred when the oldest vehicle, SVN 23, was removed from the constellation. While the core navigation systems were working normally, the coordinated universal time timing signal was off by 13 microseconds which exceeded the design specifications. The issue was resolved at 6:10 a.m. MST, however global users may have experienced GPS timing issues for several hours. U.S. Strategic Command's Commercial Integration Cell, operating out of the Joint Space Operations Center, effectively served as the portal to determine the scope of commercial user impacts. Additionally, the Joint Space Operations Center at Vandenberg AFB has not received any reports of issues with GPS-aided munitions, and has determined that the timing error is not attributable to any type of outside interference such as jamming or spoofing. Operator procedures were modified to preclude a repeat of this issue until the ground system software is corrected, and the 50th Space Wing will conduct an Operational Review Board to review procedures and impacts on users. Commercial and Civil users who experienced impacts can contact the U.S. Coast Guard Navigation Center at (703) 313-5900. V/R Rick Hamilton CGSIC Executive Secretariat GPS Information Analysis Team Lead U.S. Coast Guard Navigation Center 703-313-5930 ___ CGSIC one-way mailing list Unsubscribe: http://www.navcen.uscg.gov/?pageName=listserverunsubscribe=cgsic ___ 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.