3:22 - Just a slight correction you need to know the other numbers & letters, and they are not always for larger scale maps. 10T is the Grid Zone Designation (basically the UTM zone of the map), maps sometimes can be outside of UTM zone, so this is fine & you can ignore it unless you're reporting your location to a unit outside of the Grid Zone (i.e. outside of the map). The real issue is the second pair of letters - "FR", that's the 100,000 meter square identification, in some situations you may have a map which is within the X of where four different 100,000 Meter squares intersect. Essentially you'll have four different 100,000M square identifiers e.g. FN, FM, GM, GN.
Little correction in your example: The second pair of letters “FN” corresponds to a 100 x 100 Km square = 10,OOO square Km. NOT 100,000square meters (that’s a very big difference). 100,000 square meters is a surface of ± 318 x 318 meters far away of the 100 x 100 KM or 10,00 square Km. If you stay in that 100 x 100 Km square you also can ignore the FN letters. But if you go outside of your UTM-zone (in the video 10T) than you have the problem with the pair of letters that do not connect to the previous zone. For that you need a table to find the right letters or you really have to know the MGRS coordinate system very, very, very well. Knowing that table by heart is so difficult maybe even impossible. If you have the connecting map then you should be able to find those letters on the map (if they are printed on it). If not, Succes.
@@ervano798 Oh, I get where the disconnect comes from. I mean square as a grid square, not as in the area of a square. The second pair of letters in MGRS is commonly referred to as a 100,000m square identifier.
Does this only work with specific kinds of maps? Say the event creator just creates a map and adds his own grid system. Is this still applicable? Or does scale of the map effect this method? TIA
Yes the maps must be MGRS. There are web sites that will create these maps for you to print off of the AO of your choice. Just make sure the scale is the same as your protractor. Sometimes you have to mess with your printer settings to get the correct scale.