); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] RETRY In a message dated 02/09/2007 04:20:54 GMT Daylight Time, [EMAIL PROTECTED] writes:
It is amusing/distressing to see that the myth that using an FLL to lock an oscillator to the PPS output of a GPS receiver is a good approach still persists. The optimum solution is a phase lock loop. Whilst building an FLL is instructive/educational, if you want the best GPSDO performance you should really use a PLL. -------------------- Perhaps it depends on how you define a "good" approach. If you're looking for the very best you can get then it probably isn't, but I don't recall that being claimed in the first place. However, one of the attractions has to be the simplicity of the circuit and the fact that something offering reasonable performance can be knocked up very quickly. Without the divider and buffers, the circuit proposed by Bertrand Zauhar, VE2ZAZ, in his QEX article reduces to just three ICs. It may not be optimum but it must be a strong contender for the best you can get for very little effort. The Idaho State University version is reported on their web page for the project as having been checked over a 13 day period, by the Idaho National Laboratories Calibration Lab, and found to be accurate to 1.2x10^-10. I don't think that's too bad for a fun project that could probably be put together in an evening, even for one guilty of causing such amusement and/or distress:-) regards Nigel GM8PZR _______________________________________________ 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.
