The minimum number of satellites needed to show your position on the GPS device is 3. A signal from one GPS satellite will just tell your distance from that particular satellite. If you know your approximate latitude and longitude, you can figure out which point you are at. Four satellites are necessary to accurately determine altitude.
First digital camera
The first digital camera was designed by a Kodak engineer by the name of Steven Sasson. It weight 3.6 kg and was the size of a toaster.
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Minimum satellites to know position on GPS