[time-nuts] Tbolt issues
csteinmetz at yandex.com
Thu Sep 1 16:26:48 EDT 2016
> No, again it sounds like you have a bad TBolt. Or something is wrong (antenna? reception? time constant? environment? China resoldered parts?). I appreciate that Juerg did lots of testing -- do you happen to have his ADEV plot?
> Your claim of 1e-10 is order(s) of magnitude worse than the TBolts that I see. Something is wrong.
I second that (not that any further evidence is necessary following
Tom's comprehensive response). Additionally, as far as I know, the
units Tom was testing would have had the default tuning parameters (Tom,
please comment). Most Tbolts I've seen can be tuned for much better
performance than this at tau > 100 seconds, if they are equipped with a
Note that the Tbolt has tuning parameters that limit how far the
frequency is allowed to wander to adjust the PPS phase -- if Bert's
unit(s) have these parameters set to allow very fast PPS recovery, that
could well cause the behavior he describes.
You should also check all of the other tuning parameters to see if there
are errors in the settings.
However, rather than mucking about in the myriad tuning settings
starting where they are now, I recommend doing a full factory reset to
get all parameters back to the original settings. Then (after several
weeks of undisturbed running), compare ADEV performance with Tom's graphs.
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