The lowest cost solution is a DS chip in combination with a PIC. How ever has any one thought about a fix by going to the source of the problem. The TCXO. Use a DDS with internal multiplier like the AD9851 or AD 9913 and use the sawtooth message from the GRS receiver and change the frequency. An other alternative would be to use the sawtooth word to fine tune a TCXO or any VCXO for that matter. Bert Kehren In a message dated 3/25/2014 7:28:11 A.M. Eastern Daylight Time, p...@phk.freebsd.dk writes:
In message <6b362a4d-834a-4733-bed8-fcfec0ccb...@rtty.us>, Bob Camp writes: I should add here, that you _can_ do a little bit better than the sawtooth correction. We know, or at least assume, that the GPS's internal clock is step-less and slowly changing, so if you put a predictive filter on this stuff, it can actually do a reasonable job at estimating which way the rounding of the sawtooth correction went (since it is integral ns). This reduces the random rounding error on the sawtooth correction from +/- 0.5 ns to something like +/- 0.3 ns. Totally not worth it, but a cool and educational project :-) -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _______________________________________________ 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. _______________________________________________ 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.