[ntp:questions] timing issue with a HP 58534A

Mark C. Stephens marks at non-stop.com.au
Sat Feb 4 15:34:50 UTC 2012


Dave,


Definitely doesn't work without fudging 500ms

I dragged the scope down to the lab and found 2 issues, first, the PPS pulse was inverted.

Secondly, the cable between the smart antenna and the interface box was picking up RF from the repeater next door.

I also noticed that the rs422 lines were not terminated.

So that's all been fixed up now and the latest result is:


[root at NTP ~]# ntpq -p
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
*GPS_NMEA(0)     .GPS.            0 l    1   16  377    0.000  174.767  36.277
+time.non-stop.c 203.35.x.x    2 u   44   64  377    0.348  366.648 117.149
+ns1.unico.com.a 203.23.237.200   3 u   60   64  377   27.930  402.659 145.205


However in the log there a a number of:

5 Feb 02:30:59 ntpd[6493]: frequency error 504 PPM exceeds tolerance 500 PPM
5 Feb 02:31:15 ntpd[6493]: frequency error 503 PPM exceeds tolerance 500 PPM

I let it settle and see how it goes, then try to remove the internet NTP server. I am worried that that isn't there, our house ntp will get flagged as false ticker again.


Thanks for everything,
Mark


-----Original Message-----
From: Mark C. Stephens 
Sent: Saturday, 4 February 2012 11:54 PM
To: 'Dave Hart'
Cc: questions at lists.ntp.org
Subject: RE: [ntp:questions] timing issue with a HP 58534A

Yes, you are right added 'fudge time2 -0.5'

[root at NTP ~]# ntpq -p
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
*GPS_NMEA(0)     .GPS.            0 l   16   16  377    0.000   -0.304   0.035
+admin.non-stop. 203.35.x.x    2 u   50   64  377    0.336  -17.013   0.124
 130.220.30.32   .STEP.          16 u    - 1024    0    0.000    0.000   0.000
 chronos.ise.can .STEP.          16 u    - 1024    0    0.000    0.000   0.000
-ns1.unico.com.a 203.23.237.200   3 u   13   64  377   27.789  -24.321   4.624
+ntp.hiltech.com 149.20.64.28     2 u   61   64  377   74.266  -13.340   1.541

How do I check if ntpd is using PPS pulse?

I still have to check the PPS pulse with a scope .


Mark




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