Does temperature affect clocks?
"Arny Krueger" wrote in message
...
Most crystals are +/- 0.005% tolerance or better at 20 degrees C.
0.005% over 70 minutes is about a quarter of a second.
You forgot the percent sign (an easy mistake). It would actually be a bit
over 0.002 seconds.
So, half the problem you observed was *not* due to temperature but
due to random variations in initial value of clock frequency in just one
of the two devices involved.
So, there's two devices and if they happen to be at opposite ends of
tolerance, we've predicted your actual problem, no? ;-)
No. Probably not.
A half-second over 70 minutes is a fairly severe timing error (in terms of
the real-world TB stability possible), though well-within the range that a
DAC can (or should be able to) lock onto. * Whether it constitutes a
/practical/ problem depends on whether you're able to achieve and maintain
sync over the 70 minutes.
* Your average DAC has no trouble locking onto the 44.058kHz sampling rate
from a video-based digital recording system (eg, the PCM-F1).
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