In a message dated 12/11/2007 13:14:14 Pacific Standard Time, [EMAIL PROTECTED] writes:
>Why not lock it to a GPS timing receiver output when its at home, and >allow the controller to learn the aging and tempco characteristics etc >of the oscillator being disciplined and use this information to correct >for temperature variations etc at the remote site? >The model used can be as complex as required to achieve the desired >performance and a PC can be used to derive optimum correction >coefficients, the micro only has to perform the simpler task of applying >these corrections. >Bruce Hi Bruce, the problem with that is that OCXO retrace can really suck. Some common OCXO's have parts in E-09 and even worse retrace. Doing about 10 minutes of Auto Survey on an M12+ receiver and OCXO warmup, followed by about 20 minutes of active GPS locking will get you much better performance than the OCXO retrace can achieve itself. It would be interesting to see if OCXO retrace is very repeatable, if yes it could be compensated for of course. Or leave the power on at all times after calibration. bye, Said **************************************See AOL's top rated recipes (http://food.aol.com/top-rated-recipes?NCID=aoltop00030000000004) _______________________________________________ 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.
