On 10/3/07, John Pettitt <[EMAIL PROTECTED]> wrote: > I know, and the accuracy was ~1ms due to variations in propagation delay > and often worse due to poor reception during daylight hours requiring > the machine to hold over on its internal clock until the radio clock was > available again. I've got three radio clocks in my house and all of > them will only sync at night.
WWVB and the other LF stations (such as DCF77 IN Europe) produce ground-waves, so the propagation delay should be very constant. Assuming you can use some form of antenna (even indoors), reception should not be a major issue in the continental USA. As NIST says: "The frequency uncertainty of the WWVB signal as transmitted is less than 1 part in 10^12. If the path delay is removed, WWVB can provide UTC with an uncertainty of less than 100 microseconds. The variations in path delay are minor compared to those of WWV and WWVH. When proper receiving and averaging techniques are used, the uncertainty of the received signal should be nearly as small as the uncertainty of the transmitted signal." -- RPM _______________________________________________ timekeepers mailing list [email protected] https://fortytwo.ch/mailman/cgi-bin/listinfo/timekeepers
