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iBlue 747A+ delivers wrong date

Back from our vacation in the Bavarian Forest, I noticed that my long-serving and really reliable iBlue 747A+ GPS logger apparently stopped working: it delivered tracks with a date around year 2000. Investigating this further, I found that the time appeared to be okay, but the date was completely wrong.

Fortunately, the device isn't broken, it was just hit by the GPS Week Number Rollover, that took place on 2019-04-07. This really sucks! But blessedly, I can continue using the logger. One can fix the wrong date by adding 172,032 hours to the date (that is: 1024 weeks times 7 days times 24 hours).

This can be done via gpsbabel in the following way (assuming we have a GPX encoded GPS data file):

gpsbabel -t -i gpx -f original.gpx -x track,move=+172032h -o gpx -F fixed.gpx

Maybe, this will help somebody.

Hopefully, Europe's Galileo GNSS won't suffer from such shortcomings and my next "GPS" logger will use this one … and the good ole' one will continue working a few years until Galileo is finished, working and a lot of devices support it ;-)