Hi The temperature of the crystal is driven by the oven design. AT / SC / BT / IT or whatever …. it is going to be over 80C. It’s not a function of the crystal. It is what the physics of the oven force you to do. Inner oven *must* be hotter than outer oven. Outer oven *must* be hotter than the maximum ambient of 50C.
Bob > On Feb 16, 2021, at 6:17 PM, paul swed <[email protected]> wrote: > > Hello to the group still working and decoding the AN/URQ-13 reference > oscillator. Bob had mentioned that the crystal should be at 85 C and thats > right for a SC cut crystal. Would there be any reason that this oscillator > is perhaps a AT cut crystal thats in the 30 C range. Just odd that the > front meter reads in the normal temperature range and the real > measurement is 40C. Makes no sense but they build AT cut crystals for some > reason. > Ehat about the smaller ovens like Piezo's. Pretty sure I can find many > details on the Morion oscillators like the MV200. > > Other bits of details. > There are 2 discreet regulators that simply produce most likely a low > noise +/-8.5V. The Oven heaters seem to run on +15V and the divider analog > circuits need 13V min to work. But not 15V. That seems to cause some > distortion. > The other circuit on the board attached to the oscillator is a buffer amp. > It does have several meter resistors on it also. > > Regards > Paul > _______________________________________________ > 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.
