That’s not a problem, that means you’re phase locked instead of just frequency locked.
This is the phase-nuts mailing list, right? :-) Tim N3QE > On Dec 14, 2017, at 6:19 PM, Alan Melia <alan.me...@btinternet.com> wrote: > > I dont think working that way would give a stable clock in the UK. Our > frequency can vary more than the US but the number of cycles between 0800 on > one day and the next is mandated to be correct (I presume +/- 25 :-)) ). So > you would be chasing a moving target, and at no time of the day need the > frequency be 50.000Hz > > Alan > G3NYK > > ----- Original Message ----- From: "Jim Harman" <j99har...@gmail.com> > To: "Discussion of precise time and frequency measurement" > <time-nuts@febo.com> > Sent: Thursday, December 14, 2017 10:08 PM > Subject: Re: [time-nuts] accurate 60 hz reference chips/ckts > > >> Since the power line has the desired long term stability but is poor on the >> short term, I wonder if a solution might be to use it as the reference for >> a "power line disciplined oscillator." >> >> You would want a filter time constant of several hours in the control loop >> to smooth out the variations in the 60 Hz. >> >> Or it might be easier to rip the guts out of the Radio Shack clock, just >> keeping the display, and drive the display with an Arduino and a DS3231 RTC >> chip as the reference. >> >>> On Thu, Dec 14, 2017 at 4:05 PM, Hal Murray <hmur...@megapathdsl.net> wrote: >>> >>> >>> apollo...@gmail.com said: >>> > Want to provide an accurate (relatively accurate) 60 hz reference to > >>> > the >>> > chip. Some room inside for custom modifications. Does a TCXO or >>> similar >>> > exist in a small package that provides 60 hz ticks? >>> >>> I doubt if you will find a TCXO that puts out 60 Hz. But it's only one >>> chip >>> to make a divider. The trick is to do it in software rather than hardware. >>> >>> The real question is what sort of error pattern are you interested in. The >>> power company has good long term stability. How good is your TCXO? It >>> would >>> be fun to play with the numbers. On the other hand, can you derive your 60 >>> Hz from a GPSDO? >>> >>> -- >>> These are my opinions. I hate spam. >>> >>> >>> >>> _______________________________________________ >>> 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. >>> >> >> >> >> -- >> >> --Jim Harman >> _______________________________________________ >> 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. > > _______________________________________________ > 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. _______________________________________________ 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.
