[time-nuts] Turning off PPS when not enough satellites

[Poul-Henning Kamp]

In message <20060731163748.E3FAEBDF0 at ip-64-139-1-69.sjc.megapath.net>, Hal Murray writes:
>>1PPS -- Lastly, there is one convention I found handy
>>with 1 PPS sources, specifically those GPS boards
>>that are designed to suppress the 1PPS signal when
>>they loose lock.
>
>Does anybody have a list of which GPS devices do that?
>
>I have 2 data points:
>  Garmin GPS 18 LVC does not.
>  GPSClock 200 does.

the motorola UT, UT+, and M12 timing products can turn off PPS when it
cannot mathematically prove that time is within a certain timeband
around UTC.

I usually configure it for 1 microsecond, and it actually works pretty
well:

	http://phk.freebsd.dk/20040101svn23/

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