[time-nuts] Re: Symmetricom XLi question

[paul swed]

I will agree with you Bob. But those are the best opportunities to
experiment and learn.
With a bit of luck he can find the 15 pin diagram and with a drop more luck
the lamp signal (Or not). There is always the old open it up and see if the
lamp ignites. Only taking apart as little as possible to get in. Thats
still a lot. If there is light then it gets really messy reverse
engineering the photocell out and temp controllers RF etc. Since winters
coming what a great project. Humor intended.
But the good news is there is a possible chance to recover it.
Regards
Paul
WB8TSL


On Wed, Sep 21, 2022 at 4:59 PM Bob kb8tq <kb8tq at n1k.org> wrote:

> Hi
>
> The Symmetricom X72 GPS is indeed a compact Telecom RB. Like pretty much
> all of them,
> there is no real source for schematics or troubleshooting. The normal
> approach for a dead
> one is to send it back to the factory. Even working out minor things isn’t
> very easy.
>
> Bob
>
> > On Sep 21, 2022, at 1:46 PM, paul swed via time-nuts <
> time-nuts at lists.febo.com> wrote:
> >
> > Well the easy thing is to check the supplies. But that will end up being
> 1
> > supply typically something like 21-24 volts. I am guessing the RB is a
> > typical telco Rb. These are small units. There is a good chance the lamps
> > not lit. Depending on the actual unit like a FRS they actually have
> signals
> > to show the lamps lit or not. From that point you can try to figure out
> > what the next step is.
> > Regards
> > Paul
> > WB8TSL
> >
> >
> > On Wed, Sep 21, 2022 at 2:35 PM Mark G Thomas via time-nuts <
> > time-nuts at lists.febo.com> wrote:
> >
> >> Hi,
> >>
> >> I just received an XLi from e-bay. It unexpectedly has the Rubidium
> >> standard, in addition to the GPS receiver 87-8028-2.
> >>
> >> I have not yet determined if my 87-8028-2 is affected by the week 1024
> >> rollover bug. After 12 hours it has finally transitioned from "SITE
> >> SURVEY" to "TRAIM ACTIVE", but still not GPS locked.
> >>
> >> Claude -- which exact Jackson Labs part did you use?
> >>
> >> Unfortunately the X72 RUBIDIUM OSC is in FAULT state.
> >>
> >> I am interested in any recommendations about what to do about the failed
> >> rubidium. My next steps will be to check supply voltages and pull out
> >> the 87-8028-2 to see which GPS module it has, but I was hoping it would
> >> get GPS lock before I shut it down again.
> >>
> >>> F18
> >> F18 BOOTLOADER  192-8000
> >>     SOFTWARE    192-8001
> >>     FILE SYSTEM 192-8002V2-4
> >>     PROJ REV #  2-4
> >>     FPGA #      184-8000V65
> >>
> >>> F72
> >> F72 CLOCK PLL              LOCKED
> >>     CLOCK STATUS           UNLOCKED    GPS PRI
> >>     PRIMARY POWER SUPPLY   OK
> >>     SECONDARY POWER SUPPLY OK
> >>     RUBIDIUM OSC           FAULT
> >>
> >>> F108
> >> F108 OSCILLATOR CONFIG RUBIDIUM
> >>
> >>> f60 b1 tracked
> >> F60 B1 prn2 good tracked -153dBW
> >> F60 B1 prn5 good tracked -154dBW
> >> F60 B1 prn6 good tracked -155dBW
> >> F60 B1 prn9 good tracked -157dBW
> >> F60 B1 prn11 good tracked -154dBW
> >> F60 B1 prn12 good tracked -154dBW
> >> F60 B1 prn13 good tracked -196dBW
> >> F60 B1 prn19 good tracked -162dBW
> >> F60 B1 prn20 good tracked -154dBW
> >> F60 B1 prn25 good tracked -156dBW
> >> F60 B1 prn29 good tracked -156dBW
> >>
> >>> f60 b1 current
> >> F60 B1 prn2 good current -154dBW
> >> F60 B1 prn5 good current -154dBW
> >> F60 B1 prn6 good current -155dBW
> >> F60 B1 prn9 good current -158dBW
> >> F60 B1 prn11 good current -153dBW
> >> F60 B1 prn12 good current -155dBW
> >> F60 B1 prn20 good current -154dBW
> >> F60 B1 prn25 good current -157dBW
> >> F60 B1 prn29 good current -156dBW
> >>
> >> Mark
> >>
> >>
> >> On 11/25/21 5:45 PM, va2hdd at ebox.net wrote:
> >>>
> >>>
> >>> Hi Martin.
> >>>
> >>> In my XLi the GPS is in option bay 1.
> >>>
> >>> As far as I know you can put it in any free option bay, you will
> >>> configure it in software at start up.
> >>>
> >>> In my case I had to replace the GPS receiver that was on the 87-8028-2
> >>> option card, there was a week 1024 rollover bug issue on it.
> >>>
> >>> Personally I would take the time to test it with an antenna, as the
> late
> >>> production units have a more recent GPS receiver card that has no
> >>> rollover bug.
> >>>
> >>> In my case I used the Jackson Labs replacement board, and I warmly
> >>> recommend it, it works flawlessly.
> >>>
> >>> Have fun with your XLi !
> >>>
> >>> Claude VA2 HDD
> >>>
> >>> On 2021-11-25 16:41, Martin Flynn wrote:
> >>>> Picked up a Symmetricom XLi with two A/C supplies and two empty slots.
> >>>>
> >>>> Question #1
> >>>> Is there a preference which of the two empty slots the GPS C/A
> >>>> Receiver (87-8028-2) is placed in?
> >>>>
> >>>> Question #2
> >>>>
> >>>> Anyone have slot covers sitting around?
> >>>>
> >>>> Martin
> >>
> >> --
> >> Mark G Thomas <Mark at Misty.com>, KC3DRE
> >> _______________________________________________
> >> time-nuts mailing list -- time-nuts at lists.febo.com
> >> To unsubscribe send an email to time-nuts-leave at lists.febo.com
> > _______________________________________________
> > time-nuts mailing list -- time-nuts at lists.febo.com
> > To unsubscribe send an email to time-nuts-leave at lists.febo.com
>
>