Re:Ntpd won't save you from one particular rogue bit
by Florin_Andrei on Thursday September 28, 2017 @04:39PM
(#15360528)
The vast majority of quartz references in consumer devices could be a lot better, but they are not fine-tuned at the factory. They're just "close enough". So they drift a lot.
A simple tuning procedure could make almost all quartz clocks you own a heck of a lot better. But in many cases this is hard to do because the manufacturer never put the tuning components (a variable capacitor or the like) on the PCB.
Re:Ntpd won't save you from one particular rogue bit
by monochromatic on Thursday September 28, 2017 @05:25PM
(#15360868)
That’s interesting. I’d never thought about it, but of course there’s a temperature dependence, and of course attaching it to a wrist mitigates it.
The tuning fork crystal design used in wrist watches has a parabolic temperature coefficient, which means that the clock is only really accurate at room temperature. This isn't a problem for wristwatches, because, presumably your wrist is at approximately room temperature, but it does become a problem for electronics that operate with large temperature swings. (like the inside of a phone or computer, for instance).
https://www.maximintegrated.com/en/app-notes/index.mvp/id/58