> Even if you get the crystal adjusted at the factory to say 5ppm, can > it be guaranteed that all the other effects combined stay at <45ppm > over the lifetime of the product (these days it's about 6-12 months > depending on the warranty period)?
After initial calibration, the main consideration is temperature. You should be able to get a graph from the vendor and/or make your own. It depends on the angle of the crystal cut. I've seem a graph with a family of curves at different angles. The ballpark is 1 ppm per C, so if you can limit your temperature range to room-temperature you can probably make something work. That's from my PC using NTP as a calibration. You can probably do better if you work with the vendor. Secondary considerations are power supply voltage and aging. -- The suespammers.org mail server is located in California. So are all my other mailboxes. Please do not send unsolicited bulk e-mail or unsolicited commercial e-mail to my suespammers.org address or any of my other addresses. These are my opinions, not necessarily my employer's. I hate spam. _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
