Today most quality OCXO's are in a sealed can but three of the best HP10811, Austron 1150 and OSA 8600/07 are not sealed. Austroon set screw hole has a screw with an O ring. When you try to get the best out of them not part of a loop you may have to consider compensation like with Rb's. Maybe it is not the Xtal but some other part of the circuit. Any Idea or experience. Pressure will most likely be slow. Here in Florida Hurricane is on us, maybe a time to outline a test. Bert Kehren In a message dated 8/5/2019 3:34:15 AM Eastern Standard Time, [email protected] writes:
On Sat, 3 Aug 2019 14:22:22 +0000 (UTC) ew via time-nuts <[email protected]> wrote: > Are wee missing something. Reading Bill Slade post and old NASA > attachments the attached plot to me was an eye opener. Our work > has always been focused on Rb pressure compensation. Are we > overlooking something. Has any one done some work on this subject No, we are not overlooking anything. Pressure sensitivity of OCXOs has been long known and most manufacturers account for it in their design. In most cases, the temperature induced instability is larger than the pressure sensitive effect, together with the pressure sensitivity measurement and characterisation being expensive, it does not get mentioned in the datasheets. But, if you really want to compensate for environmental effects, then you need to have a quite complex model. This makes it rather difficult to parametrize, you need measurements over months if not years. That makes these parameters also quite difficult to use, as they exhibit memory effects (e.g. hysterisis) and change over time. If you are interested in this, have a look at the fields of "System identification." Or, if you want to have it a bit simpler and more statistical: "Principal Component Analysis" Attila Kinali -- <JaberWorky> The bad part of Zurich is where the degenerates throw DARK chocolate at you. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
