On Fri, Aug 01, 2014 at 12:59:32PM +0200, Martin Burnicki wrote: > Miroslav Lichvar wrote: > >To generalize it a bit more, there could be also a case of a PPS that > >is not locked in phase and a case of a PPS that's not even locked in > >frequency. When only a source with poor short-term stability is > >available, I think it would be pretty cool if it could be combined > >with a PPS derived from a cheap TCXO. Doing this in ntpd could be > >tricky however. > > Hm, I maybe I don't understand correctly what you mean. > > You want to use a PPS signal without proper phase and frequency, and then > use *in addition* another PPS derived from a TCXO?
I meant to use a PPS signal from an external undisciplined *XO to stabilize the system clock. The driver would track the phase and frequency offsets against other sources or the system clock over a longer interval and use that to correct the samples before normal processing. I think this could be useful with jittery sources (e.g. NTP) or reference clocks that don't have their own stabilized oscillator. -- Miroslav Lichvar _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
