>We target for millisecond accuracy. As I understand, the oscillators on >standard PCs are mostly cheapest crap and there are way better >oscillators I could use to replace the original. Is that correct?
There are two parts to that "crap". One is that the actual frequency doesn't match the number printed on the can. That's not a problem because the drift file corrects for that type of error. The other is that it may be highly temperature sensitive while a more expensive crystal may be less so. You can probably measure that be heating up the box, perhaps by just running soem compute intensive task rather than letting it sit mostly idle. The suggestion for an external ovenized (OCXO) crystal/oscillator was a way to avoid the temperature shifts. The basic idea is that you run the crystal in an oven and have a mechanism to keep it at a constant temperature. (Warmer than normal is easier to implement than keeping it at room temperature. All you need is a heater, no refrigerator.) -- These are my opinions, not necessarily my employer's. I hate spam. _______________________________________________ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions