OK been only slightly paying attention. But I see in the US several sellers for a operational board at $84-89. Maybe I have the wrong unit but it does say 5ns or less timing error Regards Paul WB8TSL
On Thu, Mar 29, 2012 at 11:50 AM, Ed Palmer <ed_pal...@sasktel.net> wrote: > On 3/29/2012 12:54 AM, Ulrich Bangert wrote: > >> Thomas, >> >> The sawtooth error on the Motorola M12+ is about +/- 25ns, while the >>> CW12-TIM has a sawtooth error of +/- 2 ns, so correcting for the >>> sawtooth error is not as critical with the CW12-TIM. >>> >> The first claim >> >> The sawtooth error on the Motorola M12+ is about +/- 25ns >>> >> is correct but are you absolutely sure that the second claim is correct >> too????? >> >> It would mean a factor>10 improvement of the CW12-TIM against the M12 >> which >> is hardly believeable. >> > > Believe it. I've made multiple test runs where I use an HP 5372A to > measure 1000 pulses of the CW12. The Standard Deviation is always < 5 ns > with a max-min range of < 30 ns. That's without any type of error > correction - straight from the GPS receiver to the 5372A. A clue to the > performance is a line in the datasheet that says the clock speed is "up to > 120 MHz". Maybe not fast enough to justify +/- 2 ns., but in the ball park. > > I am rather surprised that they're adding sawtooth correction. This unit > has been around for some years. The Motorola firmware isn't even a > standard offering anymore. You have to ask for it. It'll be interesting > to see what they come up with considering that the datasheet says that the > resolution on the 1 PPS signal is "< 5 ns". There doesn't seem to be much > room for correction there. > > Ed > > > Best regards >> Ulrich Bangert >> >> -----Ursprungliche Nachricht----- >>> Von: time-nuts-boun...@febo.com >>> [mailto:time-nuts-bounces@**febo.com <time-nuts-boun...@febo.com>] Im >>> Auftrag von Tom Knox >>> Gesendet: Mittwoch, 28. Marz 2012 20:42 >>> An: Time-Nuts >>> Betreff: [time-nuts] CW12-TIM vs M12M and the world >>> >>> >>> >>> I spoke with Navsync about some of the issues we are >>> discussing and this was their response. I just received mine >>> and will try to test it over the weekend. 1. Is CW12-TIM >>> compatible with Motorola M12 ?>> The CW12 is designed to be >>> compatible with the M12 although there are >>> some differences. The main hardware differences are listed >>> on page 7 of the CW12 User Manual >>> (http://www.navsync.com/docs/**cw12-tim_um.pdf<http://www.navsync.com/docs/cw12-tim_um.pdf>). >>> 2. According >>> to the customer, M12 has a Sawtooth Correction Error& >>> Hanging Bridge Error? Does CW12 have a solution for these type of >>> errors? How these errors are taken care of in CW12?>> >>> The Hanging Bridge Error is a pattern seen in the sawtooth >>> error that >>> occurs as the local clock frequency changes. The standard Motorola >>> Binary software for the CW12-TIM does not have the sawtooth >>> correction >>> field in the @@Hn command implemented, but NavSync is currently >>> developing this and it will be available in future standard releases. >>> The sawtooth error on the Motorola M12+ is about +/- 25ns, while the >>> CW12-TIM has a sawtooth error of +/- 2 ns, so correcting for the >>> sawtooth error is not as critical with the CW12-TIM. >>> >>> Thomas Knox >>> >>> > ______________________________**_________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/** > mailman/listinfo/time-nuts<https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts> > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.