Hi You can be pretty sure that in their original installations as a reference for a cell tower, shutting the whole thing down every couple months was not part of the spec.
Bob > On Oct 12, 2021, at 12:47 AM, CFO <[email protected]> wrote: > > >>>> My Z3810 had begun to show Alarm on the GPS receiver. >>>> On Coldstart it seems like it lives for 10min or so , and the enters alarm >>>> state. >>>> I'm quite sure it's the GPS receiver that has gone to "heaven" , never got >>>> that "Coldstart" every 6 months incorporated in my routines >>>> > Well (Oopz - It is a Z3801A i have) > > I dug out the Z3801 from storage (10 months), gave it a new 48V PSU and > started it up. > To my surprise it locked to 3 sats, after a few hours. And is now happily > humming away. > I did "quick" test the old 48V PSU, loaded with 600mA. And it keept the 48V > fine, doubt it was the cause. > > The "Lady" (Heather) shows that, The "Old Lady" (Z3801A) has 122700 active > hours (14yr) > Maybe it was the GPS oscillator that needed that restart, as per the service > note. > > https://synergy-gps.com/wp-content/uploads/2019/06/VP_SERVICE_NOTE.pdf > ****** SNIP ****** > Turn off all power to the GPS unit. The unit must be completely powered down > for > at least two minutes. After two minutes, turn the power on. > > This procedure should be performed every three to six months. This will allow > the unit > to perform a self-diagnostic routine and recalibrate an internal component > for optimal > performance. > ****** SNIP ******* > > The SN explicit says "Turn off all power for minimum 2 min", would that have > influence on the OCXO stability ? > Wonder why a : *TST - Would not do it (The reboot & cal) .. Anyone have an > idea ? > > > Thank you goes to the nice person that off-list offered to have a look in the > "drawer" for a VP. > Let's see if it's still needed. > > > CFO > Denmark > _______________________________________________ > time-nuts mailing list -- [email protected] -- To unsubscribe send an > email to [email protected] > To unsubscribe, go to and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] -- To unsubscribe send an email to [email protected] To unsubscribe, go to and follow the instructions there.
