Tom, The conceptual deadlock that I would overcome is whether adjusting the C-field the Cs resonance varies, as this would impact the defition of the "second".
Thanks, Antonio I8IOV > > What is the reference used to measure stability and accuracy > > of H Masers? > > Antonio, > > Good question. > > You compare against other H-maser(s), or an ensemble of Cs > clocks, or high-precision coax, fiber, or two-way satellite links to > other timing laboratories that happen to have much better clocks. > > In general, when you have a really good clock in your lab, the > obvious way to measure its performance is to find a clock that > is 10x more accurate and compare your clock against it. > > But if you can't find a better reference, or can't afford a better > reference, or if a better reference doesn't even exist, then you > use a different trick -- you make two or three clocks of the same > design and compare them amongst themselves. > > > Do Caesium clocks have something like a C-field adjustment > > (as Rb clocks have), and in the case, what it acts upon? > > Yes, all commercial Cs clocks do have a C-field adjustment or > an internal phase micro-stepper (frequency offset generator). > This is useful since they are generally more stable (parts in 1e-13 > to 1e-15) than they are accurate (parts in 1e-12 to 1e-13). So > the C-field is the traditional way to fine-tune the frequency of the > clock. Modern Cs clocks find it easier (and perhaps more reliable) > to adjust by synthesizer than by magnetic field. > > On the other hand, laboratory Cs standards correct for all these > systematic effects and are thus about as accurate as they are > stable. If you'd like more details, let me know. > > > Thanks in advance, > > > > Antonio I8IOV > > /tvb > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
