It is important for proper system operation that the array be oriented true South (if you are located in the northern hemisphere). The directions of magnetic South and true South differ from one another depending on geographic location. This variance is called declination. Check the declination for your region in order to extrapolate true South from a compass heading of magnetic South. The map below shows the magnetic declination for the US. For example, central Oklahoma falls between the 8° E and 10° E lines. This means that the south point of a compass points about 9° W of true South. So true South is actually 9° R of where the compass points.