Nick <m...@privacy.net> wrote: > On Fri, 18 Jul 2014 23:16:57 +0000, jimp wrote: > >> Nick <m...@privacy.net> wrote: >> >> <snip> >> >>> This performance is marginal for WSJTX. I need 10ms offset or less >>> after 15 minutes. >> >> What make you think that? >> >> I see a lot of WSJTX signals that are within +/- .5 seconds and >> occasionally some over a second off and they still decode. Most seem to >> be +/- .3 seconds. >> >> We are talking about this aren't we: >> >> http://physics.princeton.edu/pulsar/K1JT/wsjtx.html >> > > Yes we are. > > My spec was based only on experience using JT65B on HF using the old XP > box which easily syncs within 10ms, and on which decodes are rock solid. > > http://www.vhfdx.de/wsjt/wsjt_user_470.pdf says... > > "You will need a method of setting your computer clock to an accuracy of > one second or better, and keeping it set. Many operators use an internet > clock-setting program, while others use a GPS or WWVB receiver." > > Thank you for helping me realise the extent of my own ignorance! > >> Though I agree ntp should be doing a lot better than you are seeing. > > Yes. I'll keep digging.
FWIW, the largest offset I've seen WSJT-X decode is 3.5 seconds and lots of DX stations are in the 1 to 2 second range. BTW, if you are not using it, JT-utilities is very handy. http://hamapps.com/ -- Jim Pennino _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
