Range Rings are circles drawn around the current GPS position (using moving map). The radius of the rings and other properties can be specified in the Range Rings Setup dialog.
Rings On - When checked the rings are drawn around the GPS position.
Ring Radius - The radius of the first ring, this is used in combination with the Radius Units below.
Radius Units - The units to use to obtain the radius distance of the first ring.
Number of Rings - How many rings to draw. Example - if you specify 3 rings are to be drawn and the radius in 1Km then the first ring is drawn at a radius of 1 Km around the GPS, the 2nd line is drawn at a radius of 2 Km, and the 3rd ring is drawn at a radius of 3 Km.
Ring Color - The color of the line used to draw the rings.
Line Width - The width in pixels of the line used to draw the rings.