sbp@bia ~
$ ntpq -p ntp1.npl.co.uk
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
+139.143.49.13   .1PPS.           1 u  321 1024  377    6.035    0.014   0.126
*139.143.49.18   .1PPS.           1 u  364 1024  377    6.095    0.030   0.093