Hi Keep in mind that the OCXO is likely (if it’s a modern part) optimized for TC at it’s normal thermal gain. The gain and set point are adjusted for a flat curve. If you bump either the gain or the set point you rotate the curve.
Bob On Aug 24, 2014, at 8:36 PM, [email protected] wrote: > Charles > I use double bobble pack inside the Alu channel and I always start out by > monitoring the OCXO and make sure it is at least 10 C below the spec range. > The tbolt is center located and I use a combination of rubber mounts but > suspended that they sell for hard drives and squares of double bubble pack. > Vibration and thermal. > Bert Kehren > > > In a message dated 8/24/2014 8:26:02 P.M. Eastern Daylight Time, > [email protected] writes: > > Bert wrote: > >> As I said before am waiting for the small spheres and will see what > happens. > > Monitor carefully, as I suspect the spheres will pack too tightly > leaving too little airspace. You could easily burn down an OCXO if > this proves to be the case and the oven control loop goes > unstable. I'd put a thermal sensor on the OCXO itself for testing. > > Even if it doesn't burn down, you could find that the oven > performance is degraded by (i) instability or quasi-instability of > the oven controller, or (ii) too much thermal resistance (remember, > you want to add as little thermal resistance as possible). > > On the other hand, mounting the OCXO as centrally as possible inside > the outer enclosure on thermally non-conducting standoffs (teflon or > nylon), with at least an inch of air on all six sides, has proven to > work extremely well. > > When I described using packing peanuts (or similar) to break up the > airflow, it was in the context of having already mounted the OCXO as > centrally as possible inside the outer enclosure on thermally > non-conducting standoffs with at least an inch of air on all six > sides. And as I said, I have not found the additional step necessary > once you have done this. It may even be counterproductive. > > 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. > _______________________________________________ > 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.
