[time-nuts] Symmetricom TS2100-GPS - 1PPS has 10uS offset

Chris Albertson albertson.chris at gmail.com
Fri May 10 17:00:05 EDT 2013

If one of the two units has a 10 uS wide pulse, I bet you have one of
the two pluses inverted.  Make sure one of the two is not flipped

On Fri, May 10, 2013 at 11:05 AM, Esa Heikkinen <tn1ajb at nic.fi> wrote:
> Hello!
> I bought Symmetricom Tymserve TS2100-GPS some time ago. When comparing it's
> 1PPS with Thunderbolt they are not in sync:
> http://www.amigazone.fi/files/gpsdo/ts2100-pps-offset.png
> Symmetricom seems to be always about 10 uSec ahead. If I turn of the power
> and then on again, it will be in sync very short moment after the tracking
> led is turned in. But then it will always roll itself at 10 uSec ahead and
> lock there, when the locked led turns on.
> It seems that it has somehow wrong GPS PPS offset or maybe it's folloring
> the 1PPS signal from it's internal GPS from the wrong edge (this is just my
> guess; Thunderbolt has 10 uSec long PPS signal, maybe the internal GPS as
> well?)
> I understand that TS2100 is not as accurate PPS source as Thunderbolt. But
> it's manual claims that 1PPS accuracy should be 1 uS. So this is clearly out
> of spec. This is strange because the Symmetricom seems to be high quality
> product. Obviously not?
> Is there any way to fix this by adjusting some offset with telnet etc? If
> not, maybe I try to invert the 1PPS from internal GPS. Or if someone knows
> how to use Thunderbolt as a time source, I could use that and remove the
> internal GPS...
> --
> 73s!
> Esa
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.


Chris Albertson
Redondo Beach, California

More information about the time-nuts mailing list