Didier Juges wrote: > One problem with that approach is that crystals that are not intended > for oven operation are optimized for minimum frequency change over 0-50 > or some other "normal" environment temperature range, and at 75 degree C > or wherever you are going to run the oven at, the temperature > sensitivity might be much greater than around 25 degrees. So even though > the oven might reduce the temperature variation by a factor of 10 or > better, the overall frequency sensitivity may not improve by the same > factor..
Of course, one could take a small Peltier device, and a resistance heater, and make a really good oven that keeps the crystal right at 25C. By having the ability to both heat, and cool the oven, you can achieve a much more precise control of the oven's temperature. A conventional oven has the ability to rapidly heat, but cooling is handled through the leakage in the oven's thermal insulation. The number of calories provided to the heater, in a conventional oven, is precisely known, but the number of calories sunk by the "cooler" (insulation leakage) varies with ambient temperature. -Chuck Harris _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
