Jun 16 21:26 2018, Björn Felten wrote to Markus Reschke:
BF> Exactly. So what's your objection?
Since the crytals's frequency drifts with the temperature there's no reason for a Swiss watchmaker to buy an expensive crystal with a low tolerance.
BF> I can't really understand why some countries have to put up with BF> 48Hz and similar, we have a rock steady 50.00000 Hz here.
That would be nice, but the frequency changes all the time (a litte bit). BTW, there are stations for recording the grid frequency az different locations and some offer their data via the internet.