Heiko Gerstung wrote: > Hi, Rob: > > Rob van der Putten wrote: >> Hi there >> >> >> Why does DCF77's phase modulation (DCFp) offer a more reliable >> timing then AM? > > From our DCF77 info page > (http://www.meinberg.de/english/info/dcf77.htm): "In order to > increase the accuracy of the demodulated time marks, the carrier of > DCF77 is additionally modulated with a pseudo-random phase noise. The > pseudo-random sequence has a length of 512 bits which are transmitted > in the time interval between the AM marks. Due to the pseudo-random > characteristics of the sequence, the mean deviation of the carrier > phase is still zero. The phase modulated carrier can be received with > a larger bandwidth. Correlation algorithms known from satellite > techniques let PZF receivers determine the correct time with an > accuracy of some microseconds which is much superior to the accuracy > achieved by standard AM receivers." >> Who produces these recievers and what do they cost? >> Is GPS better or cheaper then DCFp? > > AFAIK we (Meinberg) are the only vendors offering such a technology. > See for example: > > NTP Time Server with PZF receiver: > http://www.meinberg.de/english/products/lanpzf.htm > > Radio Clock Module > http://www.meinberg.de/english/products/pzf510.htm > > (this one can be ordered as a standalone rack-mountable system with > power supply and housing) > > and any other products with a "PZF" in their name :-) > >> Regards, >> Rob > > Kind regards, > Heiko
Heiko, Your stuff looks absolutely wonderful - I just droll and wish I could afford it! David _______________________________________________ questions mailing list [email protected] https://lists.ntp.isc.org/mailman/listinfo/questions
