[time-nuts] Improving the stability of crystal oscillators

[Bruce Griffiths]

SAIDJACK at aol.com wrote:
> Hi Rick,
>  
> thanks for the pointers to the E1938A oven quality.
>  
> Today there are some interesting new technologies which allow small double,  
> or even tripple (not sure if that makes sense) ovens to be built. Vectron for  
> example just had a lead-article in RFDesign magazine  introducing their  
> newest evacuated OCXO's.
>  
>    _http://rfdesign.com/vlf_to_uhf/time_and_frequency/709RFDF1.pdf_ 
> (http://rfdesign.com/vlf_to_uhf/time_and_frequency/709RFDF1.pdf) 
>  
> They claim stabilities on the order of 2E-07 over a very wide temp  range of 
> -40 to +85C in a DIP14 can.
>  
> The 1/2 size DIP8 can is supposed to be available end of the year with  
> similar performance.
>  
> Those small cans and wide operating ranges should make it possible to build  
> a nice small and inexpensive oven. If one can get a true thermal gain of  
> 1000+, then that would theoretically mean stabilities approaching 2E-010  over 
> temperature. That's 1.6E-012 per degree Celcius.
>  
> bye,
> Said
>   
Said

The lack of radiation shields and an isothermal block enclosing the
oscillator components within the vacuum will surely reduce the
performance somewhat.

Bruce