"Investigators have uncovered the problems behind the failure of atomic clocks onboard Galileo satellites, the European Commission said." See: http://galileognss.eu/problem-behind-failing-clocks-identified/ May be of some interest. Cheers, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-taylor@blueyonder.co.uk Twitter: @gm8arv

Hmmm Tantalum caps perhaps. My guess. But really no details. Curious though. Regards Paul WB8TSL On Sat, Jul 22, 2017 at 3:10 PM, David J Taylor via time-nuts < time-nuts@febo.com> wrote: > "Investigators have uncovered the problems behind the failure of atomic > clocks onboard Galileo satellites, the European Commission said." See: > > http://galileognss.eu/problem-behind-failing-clocks-identified/ > > May be of some interest. > > Cheers, > David > -- > SatSignal Software - Quality software written to your requirements > Web: http://www.satsignal.eu > Email: david-taylor@blueyonder.co.uk > Twitter: @gm8arv > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/m > ailman/listinfo/time-nuts > and follow the instructions there. >

sounds like they have to go up and re-cap the sats… Isn’t that the first thing the typical forum reader does? > On Jul 22, 2017, at 12:10 PM, David J Taylor via time-nuts <time-nuts@febo.com> wrote: > > "Investigators have uncovered the problems behind the failure of atomic clocks onboard Galileo satellites, the European Commission said." See: > > http://galileognss.eu/problem-behind-failing-clocks-identified/ > > May be of some interest. > > Cheers, > David > -- > SatSignal Software - Quality software written to your requirements > Web: http://www.satsignal.eu > Email: david-taylor@blueyonder.co.uk > Twitter: @gm8arv > _______________________________________________ > 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.

Hi Is there more detail on what they found? Bob > On Jul 22, 2017, at 4:38 PM, Jerry Hancock <jerry@hanler.com> wrote: > > sounds like they have to go up and re-cap the sats… > > Isn’t that the first thing the typical forum reader does? > > > >> On Jul 22, 2017, at 12:10 PM, David J Taylor via time-nuts <time-nuts@febo.com> wrote: >> >> "Investigators have uncovered the problems behind the failure of atomic clocks onboard Galileo satellites, the European Commission said." See: >> >> http://galileognss.eu/problem-behind-failing-clocks-identified/ >> >> May be of some interest. >> >> Cheers, >> David >> -- >> SatSignal Software - Quality software written to your requirements >> Web: http://www.satsignal.eu >> Email: david-taylor@blueyonder.co.uk >> Twitter: @gm8arv >> _______________________________________________ >> 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.

Hi, I have heard that there might have been testing procedures that could have damaged a component so that it slowly develops into a full problem later. This have obviously been known for some time, but the extent of real failures was not known. I would guess that over-voltage can have created a small break-through that ends up going short over time. An experienced guy like you will be able to make a couple of guesses. Cheers, Magnus On 07/22/2017 11:28 PM, Bob kb8tq wrote: > Hi > > Is there more detail on what they found? > > Bob >> On Jul 22, 2017, at 4:38 PM, Jerry Hancock <jerry@hanler.com> wrote: >> >> sounds like they have to go up and re-cap the sats… >> >> Isn’t that the first thing the typical forum reader does? >> >> >> >>> On Jul 22, 2017, at 12:10 PM, David J Taylor via time-nuts <time-nuts@febo.com> wrote: >>> >>> "Investigators have uncovered the problems behind the failure of atomic clocks onboard Galileo satellites, the European Commission said." See: >>> >>> http://galileognss.eu/problem-behind-failing-clocks-identified/ >>> >>> May be of some interest. >>> >>> Cheers, >>> David >>> -- >>> SatSignal Software - Quality software written to your requirements >>> Web: http://www.satsignal.eu >>> Email: david-taylor@blueyonder.co.uk >>> Twitter: @gm8arv >>> _______________________________________________ >>> 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. >

> http://galileognss.eu/problem-behind-failing-clocks-identified/ > http://galileognss.eu/atomic-clocks-failures-onboard-galileo-satellites/ > My guess. Perhaps a time nut will eventually find and share a technical paper with all the details. Meanwhile, let's not use time-nuts as a public guessing forum. Some background on the Galileo clocks, including photos and ADEV plots: "The Onboard Galileo Rubidium and Passive Maser, Status & Performance" http://www.spectratime.com/uploads/documents/ispace/PTTI_FCS_RAFS_PHM_2005.pdf "Space Passive Hydrogen Maser Performances, lifetime data and GIOVE-B related telemetries" http://www.unoosa.org/documents/pdf/psa/gnss/ignss2009/08.pdf "Synchronizing 30 navigation satellites within 1 ns" http://www.ion-ch.ch/media/navigare09/Navigare09_Rochat.pdf "Latest & future Evolutions on Atomic Clocks for Global Navigation Satellites" http://ec.europa.eu/DocsRoom/documents/19185/attachments/88/translations/en/renditions/native [ 04_28 September - Session 6 - Panel 6.1 - Pascal Rochat, Spectratime.pdf ] If anyone has additional technical links to Rb and PHM clocks used for GNSS, feel free to post links. Thanks, /tvb ----- Original Message ----- From: "paul swed" <paulswedb@gmail.com> To: "David J Taylor" <david-taylor@blueyonder.co.uk>; "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Sent: Saturday, July 22, 2017 12:45 PM Subject: Re: [time-nuts] Problem behind failing Galileo clocks identified > Hmmm Tantalum caps perhaps. My guess. > But really no details. Curious though. > Regards > Paul > WB8TSL > > On Sat, Jul 22, 2017 at 3:10 PM, David J Taylor via time-nuts < > time-nuts@febo.com> wrote: > >> "Investigators have uncovered the problems behind the failure of atomic >> clocks onboard Galileo satellites, the European Commission said." See: >> >> http://galileognss.eu/problem-behind-failing-clocks-identified/ >> >> May be of some interest. >> >> Cheers, >> David