I find it amazing that in order to save 2cents on a crystal they are still building the Nano V3 with a resonator. That makes it useless for accuracy over outside temperature ranges of from-40C to +50C. Too bad, it's a good form factor for embedded systems, but even the Chinesewho copied it are doing the same thing.
I need to keep a 1 khz square wave stable. Sure, I can add a thermostat but it's not cost efficient.
Within 1%over 90C range.
A crystal is a crystal, but one resonator is not the same as another - is your spec the one they are using? Probably not.
Too bad, it's a good form factor for embedded systems...