Minor Locator - The Maidenhead Locator system is based on Locator Fields and a particular location is normally specified with six characters. The world is divided into 18 x 18 locator fields, each overing an area 20 degrees East - West and 10 degrees North - South. The naming of these fields begins with AA and ends with RR.Each locator field is further divided into 100 Locator Squares (actually rectangles), that each cover 1 degree North - South and 2 degrees East - West.
For accuracy down to only a few km, locator squares can be further subdivided into 24 x 24 sub-squares by adding two extra digits from AA to XX.
My locator is QF23FF. The locator field is represented by QF, the locator square by 23 and the sub-square by FF.
The Zoom Minor Locator will zoom into the map with one Locator Square occupying the majority of the window. The locator square in the above image is 23 in the QF Locator Field.