Hi, I am making an NMEA (GPS) signal tracker. (NMEA data is sent from satellites, funcubes plus many more objects e,g, animal tracking) and will be used to aim it's antenna toward the signal for better reception. I assume that this is used for telescope aiming also. The data includes location. Follow the link for information: http://www.gpsinformation.org/dale/nmea.htm What I am hoping for is a calculation between two of these points. 1/Tracker and 2/target. Is anyone willing to help me please? Cheers, Camerart.