David L. Mills wrote: > In regards to how the clocks work, all the above WWV clocks use the > munutes and seconds pulses as well as he 100-Hz subcarrier modulation. > The PSTI/Traconex clock uses a comb filter for the seconds pulse and > brute force for the subcarrier demondulation. The NTP WWV driver is a > mathematically optimum linear receiver with a ton of DSP algorithms. > > I have no experience with European and Japanese broacasts but assume the > DCF-77, MSF, HBG and JJY services are equivalent to WWVB. It looks like
DCF-77 is not equivalent at all, it is in fact much better! :-) With the right gear, you can sync to the gps-like pseudorandom modulation of the DCF-77 carrier phase, this allows you to determine pulse transitions at approx 15-30 us level. You still have to correct for transmission delay, which means that such a fancy receiver is only useful when you're close enough to the transmitter that the direct ground wave dominates the received signal. Terje -- - <[EMAIL PROTECTED]> "almost all programming can be viewed as an exercise in caching" _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
