[time-nuts] GPSDO control loops and correcting quantizationerror

[Poul-Henning Kamp]

In message <CE93652A-1DA6-48E3-9883-D7616AC24A78 at rtty.us>, Bob Camp writes:

Bob,

There's one thing makes me scratch my head here:  Why do you keep
arguing like the timeconstant cannot be changed dynamically ?

I use a very aggresive timeconstants initially, to quickly get the
phase offset under control, and then I ramp up the timeconstant in
order to reduce phase noise of the GPS, until I hit something which
looks like the "Allan-intercept" (as Dave Mills calls it).

It' won't take long time for us to agree that the timeconstant
is a tradeoff between phase and frequency error, but just because
it is called a "timeconstant" doesn't mean we cannot change it.

-- 
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