LF diurnal variations are considerable, in the many microseconds range. Thus any claim of parts in 10^13 or 10^14 or 10^15 accuracy is misleading.
Even one microsecond of atmospheric phase change over an hour is equivalent to a 2.7e-10 apparent frequency offset. Cal labs that still use LF signals average over an integral number of days to try to reduce this effect. Or they upgrade to GPS where diurnal variations are a hundred to a thousand times less. /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.
