Now there's an interesting project: turning Bert's board into a controller for an Rb standard. = ) If I'm reading the manual right it says: "For an FE-5680A device with an output frequency of 10 MHz, this corresponds to a relative frequency setting resolution of 1.7854E-14." This should be the same for a timing FE-5680A modified to accept RS-232 and output RF, right?
Bob >________________________________ > From: Bob Camp <li...@rtty.us> >To: Discussion of precise time and frequency measurement <time-nuts@febo.com> >Sent: Sunday, October 13, 2013 3:06 PM >Subject: Re: [time-nuts] Trimble replacement part-2 > > >Hi > >All of the surplus GPSDO's are designed for cell tower applications. They are >time references rather than frequency references. That's true of a TBolt, the >HP 38xx's, the Nortel / Trimble's and the Symmetricom / Trimbles. It's also >true of many the TIme Source series of parts (for various reasons). > >If you want a unit with tight *guaranteed* frequency accuracy for a wide range >of averaging (say < +/- 10 ppt 10 seconds to forever), you want a GPS >disciplined Rb not a GPS disciplined OCXO. They are out there. Plan on >spending a couple thousand dollars. Even with those units, there is no >software that will tell you what the frequency accuracy currently is. All it >will tell you is "locked and running". To *know* that the frequency is correct >you still need an external high accuracy reference to compare to. The gizmo's >main spec is not going to be ADEV. ADEV won't tell you what the actual >frequency is. > >Bob > > _______________________________________________ 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.
