[time-nuts] Improving the stability of crystal oscillators

[SAIDJACK at aol.com]

In a message dated 10/10/2007 11:13:21 Pacific Daylight Time, jra at febo.com  
writes:

>We  first built a small proportional heater circuit that we could shove
>in  next to the crystal, and that worked OK.  We finally found a  source
>for thermistors spot welded to a spring clip that would mount  snugly
>directly to the crystal case.  With 12 volts applied, these  heated the
>crystals very nicely.  With the heaters, we were able  to keep the
>systems running year round with about 1/10 the service  calls.

Hi John,
 
interesting anecdote!
 
Would you know if the thermistors are still available? Who made  them?
 
Thanks
Said








************************************** See what's new at http://www.aol.com