Welcome to the Cuyahoga Falls Amateur Radio Club

The Third Annual Ohio 2 Meter FM Simplex Squares Contest

Grid Squares

If you consult Wikipedia (and we recommend you do for a full explanation), you'll find the Maidenhead Locator System is described as a geographic co-ordinate system used by hams. It compresses latitude and longitude into a short string of characters, pairs of letters and numbers, which describe with increasing resolution, a location in a series of rectangular grids overlaying the world map.

Essentially, the world map is divided and sub-divided into sets of grid squares within grid squares, and each one is identified by pairs of alternating letters and numbers.

Two Character Maidenhead grid squares overlaid on the world map.

For example, the grid square EN covers not only the northern half of Ohio, but includes parts of Pennsylvania, Indiana, Illinois, Missouri, Nebraska, and North and South Dakota. It also fully encompasses the states of Michigan, Iowa, Wisconsin, and Minnesota and covers most of the Great Lakes. And it reaches into parts of Ontario and Manitoba, Canada. Pretty big area!

A closer view of the area covered by the "EN" grid square.

To be able to refer to smaller areas a second pair of coordinates, this time numbers, is added to more closely define an area, for example EN91. This area includes most of Cleveland and it's suburbs, the Akron area, Youngstown, into Grove City and Meadville, Pa., Astabula and parts of Lake Erie.

The area encompassing the "EN91" grid square.

For a more exact location yet, you can add a third pair of grid square identifiers, say fd. That's a rectangle about 3 by 4 miles, and in the case of EN91fd, it extends from just east of Sand Run Road and a bit east of State Road, and a northern boundary paralleling Bath Road and a Southern boundary cutting through the middle of the Valley View Golf Club. This rectangle is mostly in the city of Cuyahoga Falls.

The area encompassing the "EN91fd" grid square.

For this contest, you will be using 6 character grid square identifiers, and you will need to know the grid square identifier for each location you operate from. Bearing this in mind, the question becomes: "How do you know which grid square you are in?" There are several ways.

If you have a smart phone (Android or iPhone) there are several apps that use your phone's GPS capability and display in real time what grid square you are located in. Some display your location on a map along with grid square boundaries and your location is updated as you move, making it very easy to tell when you cross over into another grid square. The app I recommend is called QTH which is available free through the Google PlayStore. There is an iPhone app, also called QTH, downloadable from the Apple store for a nominal fee. A friend was playing with it and it did display his grid square location, but did not seem to display a map of the surrounding area for some reason. The following is a close up of the display on my Android phone, showing my location to 8 character resolution, and the locations of adjacent grid squares. Note only the first 6 characters are used for this contest.

A close up of the display from the QTH app on my Android phone.

Lacking a smartphone, another good option is a GPS unit. Many of them can be setup to display Maidenhead Grid Squares. Check the web site:


for a list of some GPS units that can be set up to display grid squares. Don't give up if your specific unit isn't shown. Try following instructions for a similar unit. The web site has instructions on how to set up some of the listed GPS units, for others, you will have to search to find out how. Club member John (WO3X) submits the following method for a Garmin Oregon 300 (which is not listed on the above web page):

Garmin Oregon 300i

  1. Touch 'Setup'.
  2. Scroll to 'Position Format'.
  3. Touch 'Position Format'.
  4. Touch 'Position Format' if not 'Maidenhead'.
  5. Scroll to 'Maidenhead' and touch it.
  6. Touch the back arrow until the red X appears and then touch the red X to go to the main screen.
  7. Touch 'Compass'; Location displays six characters like EN91FD.

The popular Garmin 60 series can be setup as follows:

  1. Press Menu until 'Setup' icon is displayed.
  2. Press 'Enter'.
  3. Highlight 'Units' icon.
  4. Press 'Enter'
  5. Change the contents of the 'Position Format' to 'Maidenhead'.
Close up of the Garmin 60CSx GPS Unit displaying 6 character Maidenhead Grid Square information.

If you don't have a smartphone or a GPS unit that can display grid squares, your other option is to print out maps in advance that display the grid squares of locations you plan to operate from. There are several web sites that allow you to zoom into a map and by clicking on a location, see the grid square that encompasses that location. Some of the useful map based web sites are:

Some of these web sites give you a variable number of grid square characters depending on how close you are zoomed in. Make sure you are looking at 6 character grid squares.

Lastly, it is possible a ham you contact might not know the grid square coordinates of their location, but they have a GPS unit and they know their GPS coordinates. You can record their GPS coordinates in the comments section of your field log, and before you submit your contact log, go to the website http://www.amsat.org/amsat-new/tools/grids.php.

This site allows you to convert latitude and longitude coordinates to grid square coordinates.