Hi The bigger issue is: Was the “ST” version done as a low cost approach that just happened to be in the 8663 footprint? If so, the only way to know what it does / what it is would be to find the elusive spec sheet.
Bob > On Feb 2, 2020, at 5:47 PM, Magnus Danielson <[email protected]> wrote: > > Hi Nigel, > > I was about to make a similar comment. The 8663 is for sure limited by > it's size. Actually, for being Oscilloquartz they are by far not the > best or the worst, but kind of mid-range. I have OSA 8712 here, and the > even smaller one. Then there is the OSA 8666/8667 and well, I guess the > OSA 8600/8607 does not need introduction. I do not have the full OSA > range of oscillators for sure, but a fair sampling of it. > > I think we should look at the 8663 for what it intends to be, a > mid-range OCXO to address some of the telecom market needs. > > Cheers, > Magnus > > On 2020-02-02 23:37, gandalfg8--- via time-nuts wrote: >> I don't have access to the full copy of the quoted reference, so don't know >> whether or not specific part numbers are quoted, but did note from the >> abstract the comment..... >> "To allow the assembly on a board of 4TE width, the height of the OCXO is >> limited to 19 mm" >> This I would suggest could again point to the 8863, which is specified as >> having a maximum height of 19mm, rather than to the 8663 which is specified >> as having a maximum height of 25mm, perhaps to allow for some physical >> thermal insulation? >> Nigel GM8PZR >> I don't know what your definition of a "true double oven" is, but >> the 8663 definitely uses two ovens. You can find its construction in [1]. >> The basic design is that the crystal is mounted on a copper plate, which >> becomes the inner oven, that is placed in a hermetically sealed package >> that doubles as outer oven. All together is than mounted in the outer >> package. >> >> I guess the "low" performance of the double oven comes from the low >> thermal mass of the innver oven. That said, Mark did some measurements >> with the Star4 GPSDO (uses an 8663) and attested it superp holdover >> performance. >> >> Attila Kinali >> >> [1] "A new kind of view for a Double oven Crystal Oscillator" >> by Lefebvre, Weber, Aubry, 2007 >> https://doi.org/10.1109/FREQ.2007.4319182 >> (can be also found in the EFTF 2007 proceedings) >> _______________________________________________ >> 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. _______________________________________________ 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.
