Are we not overdoing it. 7E-13 for $15 KISS, and if you want to go beyond that use a $ 30 analog version. Looking right now at 1 E -14, I do se temperature influences, with my heat sink stable to .1 C. Mainly due to the fact that is only one side of the unit and it is clearly designed to use all sides for heat dissipation. Bert Kehren In a message dated 1/13/2012 5:02:48 P.M. Eastern Standard Time, [email protected] writes:
Hi What we are talking about is toggling the least significant bit in the DDS to achieve a resolution of less than that LSB. It could be done to a set period (like a PWM) or pseudo randomly to reduce the noise signature. Either way, roughly a 16 element long "period" should be quite adequate. 7x10^-16 / 16 would give us a 4x10^-14 step and a 2x10^-14 max error. Bob On Jan 13, 2012, at 4:30 PM, Don Latham wrote: > Oh, I hate to be a pedant, but are we talking about dithering, that is > random perturbations to remove things like hysteresis, or using the > finite steps as a bang-bang servo? > Don > > Charles P. Steinmetz >> Bert wrote: >> >>> wrong there is no DAC involved, it is a DDS >> >> Ahh. Not so simple, then. I still don't much like the notion of >> dithering, but it may be the only alternative. Or, as has also been >> suggested here, add a manual C-field adjustment (but that would not >> change the fact that the RS-232 adjustments would still be ~ 7e-13 >> steps). >> >> Best regards, >> >> Charles >> >> >> >> >> >> >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > -- > "Neither the voice of authority nor the weight of reason and argument > are as significant as experiment, for thence comes quiet to the mind." > R. Bacon > "If you don't know what it is, don't poke it." > Ghost in the Shell > > > Dr. Don Latham AJ7LL > Six Mile Systems LLP > 17850 Six Mile Road > POB 134 > Huson, MT, 59846 > VOX 406-626-4304 > www.lightningforensics.com > www.sixmilesystems.com > > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
