Hi Maybe we're talking about two different things here.
Simplistically, resolution is simply what the counter puts out as a usable LSB. There are a lot of examples out there that will do a one nanosecond single shot measurement. That measurement includes the normal trigger noise and "stuff" in the counter. There are a few assumptions about slew rate of the input. If I take two one shot measurements spaced 100,000 seconds apart, my resolution over that period is 1.0x10^-14. The measurement is representative of what the sources have done to that level. Weather the sources are stable to that level is independent of the resolution of the measurement. Bob -----Original Message----- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Azelio Boriani Sent: Thursday, October 04, 2012 12:27 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Best counter setting for ADEV? Yes, for a theoretical resolution of 10E-14@100K sec start with a 1nS and average for 100K seconds but ending up with a noise (an error bar) of 3E-12. On Thu, Oct 4, 2012 at 4:25 PM, Bob Camp <li...@rtty.us> wrote: > Hi > > For a *resolution* of 1.0 x 10^-14 at 1.0 x 10^5 seconds I only need a 1.0 > x > 10^-9 second reading out of the counter. Indeed, 5 or 10X more than that > would be better if I was after a 1 x 10^-14 accuracy. > > Bob > > -----Original Message----- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Azelio Boriani > Sent: Thursday, October 04, 2012 7:58 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Best counter setting for ADEV? > > Taking 10 samples from a 1nS counter leads you to a 100pS resolution but > the noise at best (if it is really random) is reduced by SQRT(10). So, as > already pointed out here, there is no real substitute for lower noise, > higher resolution measurements. > > On Thu, Oct 4, 2012 at 3:01 AM, Bob Camp <li...@rtty.us> wrote: > > > Hi > > > > A 1 ns resolution TI counter will do the measuring part just fine. > Hitting > > the number, is where it gets a bit crazy. A *good* GPSDO might get near > > that. > > > > Bob > > > > On Oct 3, 2012, at 8:56 PM, Kevin Rosenberg <ke...@rosenberg.net> wrote: > > > > > On Oct 3, 2012, at 6:52 PM, Kevin Rosenberg <ke...@rosenberg.net> > wrote: > > >> Nice plot! Yes, I'd have trouble measuring 10E-14 at 10E5 seconds. > > > > > > Sorry, 1E-14 at 1E5. > > > > > > > > > _______________________________________________ > > > 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. > > > > _______________________________________________ > 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.