Yep, I recently sorted through a bag of 100 crystals from China ($10, shipped) looking for a "good" one. They were ALL good... a complete waste of time. I was rather amazed at their consistency and performance for a 10 cent part.
Last year I bought an alarm clock / game from China (looks like 7 sticks of dynamite with an ominous circuit board / LED display strapped to it). It uses a 40 pin (AVR?) processor driven by a 16 MHz processor crystal. I have not set it in over a year and it is still within a few seconds. I suspect they measure the frequency and have a calibration tweak stored in EEPROM... but that seems excessive work for a $20 toy. I highly doubt they go as far as doing temperature compensation. Maybe they characterized a bucket of XTALs and use a generic compensation factor? ---------------------- > Yes, you can build gear to do temperature runs on crystals and sort bags > full of them. It’s likely that your whole bag of 5,000 came from the same bar and your net result will all look a lot alike….. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
