Hi Ed, Since the oscillator is typically free-running in an NCO, and periodically corrected by phase drops to stay "on frequency" the error you are seeing may be caused be the offset in your crystal, combined with the limited digital resolution of the NCO trying to correct for this offset.
If this is the case, your measured error would change with temperature. Does it do that? If yes, the NCO resolution is not fractionally corrected all the way. Replacing the on board Tcxo with an ocxo hand-tuned to the correct frequency would help, but that sort of defeats the purpose of the product.. Bye, Said Sent from my iPad On Jan 4, 2012, at 7:05, Ed Palmer <ed_pal...@sasktel.net> wrote: > On 1/4/2012 8:49 AM, Mike S wrote: >> On 1/4/2012 9:29 AM, Ed Palmer wrote: >> >>> What's the point of saying that it's "steered by GPS" when it's >>> off-frequency. What does that even mean? Does it steer the frequency to >>> keep the error constant? >> >> If it's constant, maybe they just need to re-spec it as having a >> 9.99999999985 MHz output. :-) >> > > Ooohhhh, it's a GPS steered offset generator! Now I get it! :-) > > Ed > > > _______________________________________________ > 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.
