On 11/09/2010 03:07 AM, Hal Murray wrote: > The Garmin USB 18 was much better. Unfortunately, it wasn't as sensitive as > competing units and it's been replaced by the 18x which has the typical > horrible jitter problems. I don't have a graph of the 18x handy, but here is > data from a USB 18. > http://www.megapathdsl.net/~hmurray/ntp/GPS18USB-off.gif > (The Garmin USB 18/18x units don't speak NMEA, but that's just SMOP.) >
The 18x-lvc (rs232): http://n1.taur.dk/permanent/hist3.png http://n1.taur.dk/permanent/adev3.png http://n1.taur.dk/permanent/gpst3.png (in the last plot the y axis is seconds, not nanoseconds) It is no timing receiver, but it suffices to drive ntpd. Two notes: the 18x here is configured for n...@115200, as that is what the homecooked GPSDO speaks. Otherwise the mesages pile up, moving the time message around excessively. This unit is decapsulated and sitting indoors. /Kasper Pedersen _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
