[time-nuts] Z3801A version issues - was Re: Substitute GPS in a Z3801A
I believe I've found a difference between the faulty units and the working units... The faulty ones come up as 1/1/1997 when you do :SYSTEM:PRESET, the good ones come up as 1/1/1998. Does this difference ring any bells for anyone? Matthew Kaufman On 6/24/2010 8:41 AM, Matthew Kaufman wrote: I now have *two* Z3801A units which misbehave in the following way (which this thread reminded me of): The GPS status says it acquires quite a few (5-6) satellites with high signal strength... then after a minute or two, for no apparent reason, it loses *all* of them simultaneously but immediately goes back into "acquiring" for the ones it was seeing, and a few seconds later, they're all back. During this time, survey (if in progress) is halted and then restarts and runs for a bit before halting again when it loses everything briefly again. Then, within days, the unit ends up out of lock... if I go check it, I see it doing the same thing, and when the satellites are being received it is in "fine frequency adjust" mode, but so far off the 1pps phase that it really has no hope of re-locking before the next time it drops and then reacquires all the satellites. This is independent of antenna, location, and 48v power source... one unit apparently has been this way since I got it, the other worked fine for months and then developed this problem. Without knowing more, I'm thinking it might simply be a bad GPS receiver board, thus the idea of trying to find a replacement, perhaps one that is better at staying acquired, has crossed my mind. Matthew Kaufman ___ 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] Z3801A version issues - was Re: Substitute GPS in a Z3801A
I seem to remember a rollover about then that obsoleted older gps units. On Sun, Aug 29, 2010 at 5:40 PM, Matthew Kaufman wrote: > I believe I've found a difference between the faulty units and the working > units... The faulty ones come up as 1/1/1997 when you do :SYSTEM:PRESET, the > good ones come up as 1/1/1998. Does this difference ring any bells for > anyone? > > Matthew Kaufman > > On 6/24/2010 8:41 AM, Matthew Kaufman wrote: > >> I now have *two* Z3801A units which misbehave in the following way (which >> this thread reminded me of): >> >> The GPS status says it acquires quite a few (5-6) satellites with high >> signal strength... then after a minute or two, for no apparent reason, it >> loses *all* of them simultaneously but immediately goes back into >> "acquiring" for the ones it was seeing, and a few seconds later, they're all >> back. During this time, survey (if in progress) is halted and then restarts >> and runs for a bit before halting again when it loses everything briefly >> again. Then, within days, the unit ends up out of lock... if I go check it, >> I see it doing the same thing, and when the satellites are being received it >> is in "fine frequency adjust" mode, but so far off the 1pps phase that it >> really has no hope of re-locking before the next time it drops and then >> reacquires all the satellites. >> >> This is independent of antenna, location, and 48v power source... one unit >> apparently has been this way since I got it, the other worked fine for >> months and then developed this problem. >> >> Without knowing more, I'm thinking it might simply be a bad GPS receiver >> board, thus the idea of trying to find a replacement, perhaps one that is >> better at staying acquired, has crossed my mind. >> >> Matthew Kaufman >> >> ___ >> 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] Z3801A version issues - was Re: Substitute GPS in a Z3801A
would that have shown up in a firmware version id change? try *IDN? and see if there is any correlation Matthew. Le 30/08/2010 03:23, paul swed a écrit : I seem to remember a rollover about then that obsoleted older gps units. On Sun, Aug 29, 2010 at 5:40 PM, Matthew Kaufman wrote: I believe I've found a difference between the faulty units and the working units... The faulty ones come up as 1/1/1997 when you do :SYSTEM:PRESET, the good ones come up as 1/1/1998. Does this difference ring any bells for anyone? Matthew Kaufman On 6/24/2010 8:41 AM, Matthew Kaufman wrote: I now have *two* Z3801A units which misbehave in the following way (which this thread reminded me of): The GPS status says it acquires quite a few (5-6) satellites with high signal strength... then after a minute or two, for no apparent reason, it loses *all* of them simultaneously but immediately goes back into "acquiring" for the ones it was seeing, and a few seconds later, they're all back. During this time, survey (if in progress) is halted and then restarts and runs for a bit before halting again when it loses everything briefly again. Then, within days, the unit ends up out of lock... if I go check it, I see it doing the same thing, and when the satellites are being received it is in "fine frequency adjust" mode, but so far off the 1pps phase that it really has no hope of re-locking before the next time it drops and then reacquires all the satellites. This is independent of antenna, location, and 48v power source... one unit apparently has been this way since I got it, the other worked fine for months and then developed this problem. Without knowing more, I'm thinking it might simply be a bad GPS receiver board, thus the idea of trying to find a replacement, perhaps one that is better at staying acquired, has crossed my mind. Matthew Kaufman ___ 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. ___ 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.
