Yes, and it happens a lot apparently. I.E. it looked weird, but it wasn't.
On Thu, Jan 2, 2020 at 6:05 PM Mike Hammett <af...@ics-il.net> wrote: > Was the weird clock update from GPS PRN 29 sent about 20 minutes before > midnight Moscow time just coincidence? > > > > ----- > Mike Hammett > Intelligent Computing Solutions <http://www.ics-il.com/> > <https://www.facebook.com/ICSIL> > <https://plus.google.com/+IntelligentComputingSolutionsDeKalb> > <https://www.linkedin.com/company/intelligent-computing-solutions> > <https://twitter.com/ICSIL> > Midwest Internet Exchange <http://www.midwest-ix.com/> > <https://www.facebook.com/mdwestix> > <https://www.linkedin.com/company/midwest-internet-exchange> > <https://twitter.com/mdwestix> > The Brothers WISP <http://www.thebrotherswisp.com/> > <https://www.facebook.com/thebrotherswisp> > > > <https://www.youtube.com/channel/UCXSdfxQv7SpoRQYNyLwntZg> > ------------------------------ > *From: *"Forrest Christian (List Account)" <li...@packetflux.com> > *To: *"AnimalFarm Microwave Users Group" <af@af.afmug.com> > *Sent: *Thursday, January 2, 2020 6:53:14 PM > *Subject: *Re: [AFMUG] mass GPS issues > > For us, we have only been shipping GPS+GLONASS since late in 2017 or 2018, > so this is the first GLONASS rollover for us. Remember this is still > speculation here, but I am starting to feel like this most likely will turn > out to be the underlying cause. > > All of us with the issue seem to be running AXN5.1.1 which was built at > the end of 2017. This might be specific to that firmware version/build. > > There are lots of GPS modules out there of varying quality, but few which > are really suitable for 1PPS synchronization. Believe me, I've evaluated > enough of them to know. I even evaluated a GPS module earlier this year > which was specifically targeted to timing applications (including survey-in > and single-satellite operation) and discovered that it was far worse > timing-wise than the ones we're using. The mediatek based modules seem to > be a good mix of low cost and really good 1PPS performance. Pretty much > any others are multiples of the price. This is probably why we've all > ended up using the same modules. > > But if you're looking for a cheap GPS receiver and don't care about 1PPS > you might end up with something else. And probably a different firmware > build. > > TOTAL SPECULATION: One suspicion I have is that the behavior of the > device might be related to which constellation it is preferring, because if > GLONASS is saying 2016 and GPS is saying 2020 (according to your broken > firmware), then you might find a module which thinks it's 2016 based on > GLONASS but is getting these confusing signals from GPS which says it's > 2019/2020. An alternate module that is convinced it's 2019/2020 might not > be happy about GLONASS trying to say it's 2016. The behavior would > probably have to be different in both cases and possibly would alternate > between the behaviors if one was not preferred for some RF reason. > > On Thu, Jan 2, 2020 at 5:14 PM Ken Hohhof <af...@kwisp.com> wrote: > >> I’m not sure it’s true that only Cambium products were affected. It >> appears to be more a certain 3rd party GPS+GLONASS receiver module that >> Packetflux uses in their latest production of Syncboxes and that Cambium >> apparently uses in their latest UGPS production. Are Packetflux sync >> products used to time anything but Cambium? Probably not. Certainly some >> other manufacturers must OEM that particular module, you’d think some newer >> auto GPS nav products or autosteer tractors or ICBMs or whatever must have >> gone bonkers. Even if they only use location data and not time sync or a >> 1pps signal, it seemed like the GPS sats just disappeared. >> >> >> >> Older Cambium and Packetflux products as well as Last Mile Gear CTM-1 and >> CTM-2 seemed unaffected, I assume because they used different, older >> modules inside. It’s interesting that Nate reports his ePMP APs tracked >> fewer satellites but not down to zero, and recovered without a power >> cycle. Different GPS+GLONASS module? Different firmware in the module? >> Inquiring minds want to know. >> >> >> >> >> >> *From:* AF <af-boun...@af.afmug.com> *On Behalf Of *Matt Hoppes >> *Sent:* Thursday, January 2, 2020 5:42 PM >> *To:* AnimalFarm Microwave Users Group <af@af.afmug.com> >> *Subject:* Re: [AFMUG] mass GPS issues >> >> >> >> So why didn’t this happen four years ago? And why were only Cambium type >> products affected? >> >> >> On Jan 2, 2020, at 6:13 PM, Forrest Christian (List Account) < >> li...@packetflux.com> wrote: >> >> The answer to your question is complicated. The short answer is that >> not in the way you stated it, as there isn't good enough clock hardware in >> the rackinjector to do this holdover, and the current electrical >> architecture isn't set up to permit the generation of a clock internally. >> We're looking at some options though so you might see something like this >> in the future. We're also looking at doing a hardware revision to the >> control board to permit a high quality holdover oscillator to be added. >> This work was underway well before this event, but hasn't progressed to the >> point that there are really any details as to what form this might take and >> when it might happen. >> >> >> >> On Thu, Jan 2, 2020 at 4:00 PM Eric Muehleisen <ericm...@gmail.com> >> wrote: >> >> A great feature would be for the RackInjector to generate it's own >> hold-over sync if it were to loose GPS. Any possibility of including >> something like that in the next firmware update? >> >> >> >> On Tue, Dec 31, 2019 at 8:45 PM Forrest Christian (List Account) < >> li...@packetflux.com> wrote: >> >> One note is that on later RackInjectors, rebooting the rackinjector not >> only won't reboot attached devices, it also won't reboot the GPS receiver. >> This is to permit reboots of the control interface without affecting >> connected device at all. This includes *most* firmware upgrades. >> >> >> >> So for the later boards, you'll need to reset it on the GPS status page. >> >> >> >> >> >> >> >> On Tue, Dec 31, 2019 at 6:29 PM Andreas Wiatowski <andr...@silo.ca> >> wrote: >> >> Thanks Forrest, let us know what you find. I can confirm that I have done >> the power cycle on the Rack injectors....we have seen the same issue occur >> again...feels like interference. >> >> It has been suggested by some to switch to Autosync+Freerun to avoid loss >> of client use...I guess it really depends on your networks reuse scheme. >> >> >> <image861500.jpg> >> >> *Internet.*** >> ** >> *Phone.****TV.* >> >> *Andreas Wiatowski* >> >> CEO/Founder >> >> Silo >> >> *1-866-727-4138, ext 600* <1-866-727-4138,%20ext%20600> >> >> | >> >> *andr...@silo.ca* <andr...@silo.ca> >> >> *silo.ca* <http://www.silo.ca/> >> >> >> >> <image461146.png> >> >> >> >> >> >> <image041427.png> >> >> > On Dec 31, 2019, at 8:05 PM, Forrest Christian (List Account) < >> li...@packetflux.com> wrote: >> > >> > [EXTERNAL] >> > Just an update/random informational message, a lot of which is pretty >> obvious from this thread: >> > >> > 1) As is pretty obvious at this point, something happened either with >> the GPS constellation or with the firmware which runs in the GPS module, or >> some combination of those. What many of you might not be aware of is that >> many vendors use the same GPS modules from the same vendor. Generally a >> certain portion of the uGPS, PacketFlux, ePMP all will use the same module, >> along with other vendors. Each of the vendors (including PacketFlux) has >> changed the exact model of the module over the years, for instance the >> GPS+glonass modules are in newer devices, and GPS only are in older ones. >> I'm working through determining whether this is just the GPS+GLONASS >> modules which are affected (it seems like it might be the case), or if it's >> a few different types. Note that because this seems like it might be >> confined to a certain type (or types) of module, that it might turn out to >> be only certain date/model ranges of each type of gear which are affected. >> > >> > 2) Restart of the module seems to clear the issue. For PacketFlux gear, >> anyone with a SiteMonitor or RackInjector should be able to do this >> remotely. In the SiteMonitor, the row on the binary tab is labeled >> something like 'SyncPipe power'. There might be multiple rows depending on >> how many SyncInjector/PowerInjectors you have - this corresponds to the >> power port on each injector, so you'll have to turn off the row which is >> for the unit which the GPS receiver is attached to. In the RackInjector, >> it's a bit simpler since it's just a button on the GPS page. >> > >> > 3) I'm currently working through trying to find anyone who really knows >> what went on here. None of the usual notification locations seem to have >> any data. Probably too early to tell. I might luck out and be able to get a >> GPS constellation recording I can replay here to replicate. >> > >> > One thing which might be helpful is for those of you who log this >> stuff, if you can provide a pretty close UTC time that this occurred, along >> with the approximate LAT/LONG, I might be able to correlate this with a >> specific event. >> > >> > - Forrest >> > -- >> > AF mailing list >> > AF@af.afmug.com >> > http://af.afmug.com/mailman/listinfo/af_af.afmug.com >> >> -- >> AF mailing list >> AF@af.afmug.com >> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >> >> >> >> >> -- >> >> - Forrest >> >> -- >> AF mailing list >> AF@af.afmug.com >> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >> >> -- >> AF mailing list >> AF@af.afmug.com >> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >> >> >> >> >> -- >> >> - Forrest >> >> -- >> AF mailing list >> AF@af.afmug.com >> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >> >> -- >> AF mailing list >> AF@af.afmug.com >> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >> > > > -- > - Forrest > > -- > AF mailing list > AF@af.afmug.com > http://af.afmug.com/mailman/listinfo/af_af.afmug.com > > -- > AF mailing list > AF@af.afmug.com > http://af.afmug.com/mailman/listinfo/af_af.afmug.com > -- - Forrest
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