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.
