The first GPS Week Number rollover occurred in August 1999. This marked the end of the first GPS "epoch," a 19.7-year period of time made famous because this is the period of time that GPS satellites can count the seconds of a week in 10-bit binary, until reaching the limit of 1024 weeks. At the end of the 1024 week, or 19.7-year period, the GPS clock resets. Some GPS receivers struggling during this reset, but Arrow Series™ GNSS receivers will continue to count the weeks in succession. Here's why.