The Maidenhead Locator System (Grid Squares)
In this age of GPS, cell phones, and the Internet, many have lost the ability to read a paper map. I like the conveniences all those modern technologies provide and use them myself. But, what happens when the power grid goes down, your GPS and cell phone don’t work, and you need to find or identify a location?
Well, “When all else fails… there is ham radio.”
Thanks to the ham radio community, there is a shorthand way to communicate over the air and locate any spot on the earth. They’re called grid squares (also known as the Maidenhead Locator System)… and they don’t rely on technology.
Here’s a couple good articles on grid squares:
A grid square is indicated by two letters (the field) and two numbers (the square), as in EM17… the grid square where I reside. In fact, it’s the grid square where most of us in Wichita reside. This identifier could be helpful if you’re attempting to communicate with someone, especially outside the continental U.S.
Here’s a PDF file containing the US grid square map provided by Icom america.
What if you need to identify a more precise location?
That EM17 grid square is further broken down into subsquares designated by the addition of two letters after the grid square, as EM17iq. This gets you down to an area roughly corresponding to 3 × 4 miles.
Grid square are further broken down to your precise location… right down to your backyard, as in EM17iq85es. To find this more precise grid square, you can zoom in on the map at https://dxcluster.ha8tks.hu/hamgeocoding/
Another piece of useful information is your Latitude and Longitude.
This information can be used to calculate your grid square (see https://www.amsat.org/amsat-new/tools/grids.php) or even your address (see https://stevemorse.org/jcal/latlon.php)
If you don’t know your station’s grid square and/or Latitude and Longitude, you can look it up on QRZ. It’s shown in the details tab for your station ID. Right below “Show Map” is a link to “Explore on HamGrid Maps”. This cool map even shows the locations and identities of other stations in your grid square.
Communicating your grid square may not be so important in local VHF communications. Most people would probably prefer having a street address. But for longer range HF communications, explaining your location is more complicated and thus easier via grid squares.
In some disasters, a street address can be useless and the grid square or latitude and longitude can effectively identify the specific location of the incident. Take for example the widespread destruction left from a tornado. There is nothing visible but rubble… no street signs and house markings. Think Joplin, Greensburg, and Andover.
Hopefully we will never experience TEOTWAWKI, but having knowledge of and the ability to communicate grid squares is just another prepper tool in your toolbox and will set you above the average person out there.