[ntp:questions] ACTS refclock is way off w.r.t GPS refclock

Brian Inglis Brian.Inglis at SystematicSw.ab.ca
Mon Oct 6 08:39:35 UTC 2014

On 2014-10-06 02:02, Harlan Stenn wrote:
> William Unruh writes:
>> 1200 bps is 120 characters per second. Thus the time it takes for the
>> clock to deliver a line of characters representing the time to the
>> computer is about a second. Makes it pretty hard to get ms accuracy,
> I believe the NIST hardware expects echo to be enabled and expects the
> transmit and receive delays to be the same.  In that case it adjusts the
> timing of the OTM (on-time mark) so that when the OTM changes from * to
> # the timing of that OTM compensates for the delay correction.  At
> least, that used to be the case.
> See http://www.nist.gov/pml/div688/grp40/acts.cfm
> Yes, there will still be limits to this technology, but it's not as bad
> as one might originally think.

The remote side starts with 45ms offset - try time1 .045.
Try also remove minpoll, add iburst and burst, change maxpoll to 16.
Take care. Thanks, Brian Inglis

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