Hi The main reason OCXO’s have a Vref is that an ovenized voltage source is likely to be more stable over temperature than what you can easily buy and mount on a PCB.
The gotcha is the common ground found on most OCXO’s. Putting the oven current through that ground makes keeping the Vref (and the EFC) well behaved a bit of a chore. For various reasons OEM’s have a hard time dealing with multiple grounds that have multiple purposes …. Bob > On Dec 23, 2021, at 12:47 PM, Attila Kinali <[email protected]> wrote: > > On Thu, 23 Dec 2021 14:42:27 +0100 > Wilko Bulte <[email protected]> wrote: > >> A quick experiment learned that the OCXO freq responds to the EFC voltage. >> So, looks like the Vref circuit in the OCXO has died. > > A stupid side question: Why do have OCXO a Vref output in the > first place? > > I can see that some form of reference might make stabilizing > the power in the crystal easier, but that still wouldn't make > it necessary to have an actual reference output. > > And related to that: Would supplying the voltage reference > externally, in case of a broken Vref output, work for whatever > is inside that needs this reference voltage? > > Attila Kinali > > -- > The driving force behind research is the question: "Why?" > There are things we don't understand and things we always > wonder about. And that's why we do research. > -- Kobayashi Makoto > _______________________________________________ > time-nuts mailing list -- [email protected] -- To unsubscribe send an > email to [email protected] > To unsubscribe, go to and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] -- To unsubscribe send an email to [email protected] To unsubscribe, go to and follow the instructions there.
