|
If the receiver hasn't been used in a while the almanac and ephemeris data on what satellites are out there and where they are gets out of date. The receiver first tries to "hear" the satellites it thinks are there, but if it can't hear them, it reverts to "cold" start and assumes that all satellites are visible, at the north pole and just listens to see who's there. After it gets an Ephemeris and almanac update, it positions the satellites and calculates a fix. That process can take up to 10 minutes or more, but more modern receivers can do it in a couple of minutes if you sit still. If you move, it restarts the process and has to do a lot more checking, which can push the time out pretty far.
So, it's normal behavior.
|