Maidenhead Grid Squares

World Grid Locator AtlasThe Dx Adventure Radio Club (DA-RC) is the first eleven metre radio club to officially recognise the challenging DX concept that is Maidenhead Grid Squares.  In fact, a grid squares event involving members is planned for 2010 and the DA-RC Achievement Program even offers an award recognising the feats of eleven metre grid square hunters!

What are Maidenhead Grid Squares?

The Maidenhead Locator System is a geographic coordinate system used by amateur, and now eleven metre radio operators, which compresses latitude and longitude into a short string of characters.  Maidenhead locators are also commonly referred to as grid locators or grid squares, despite having a non-square shape on any non-equirectangular cartographic projection.  Essentially, these locators represent a position on Earth based on latitude and longitude.

How Does the System Work?

In accordance with the Maidenhead Locator System, the Earth is divided into 324 large areas.  These areas cover 10 degrees of latitude by 20 degrees of longitude and are called ‘fields’.  Each field is divided into 100 squares.  This is where the name ‘grid squares’ comes from.

In addition, each of these 100 squares represents 1 degree by 2 degrees.  This gives us our own unique grid square which is what most DXers will exchange during a QSO and also what is used for awards such as the DA-RC Century Club award (See )

The two letters that follow a grid square further define the operator’s QTH within that square by dividing each square into a sub-square.  Each sub square is equal to 5 nautical miles by 2.5 nautical miles.  So as you can see, one grid square covers a large area!

Maidenhead Grid SquaresFinding your own Grid Square/Locator

Many utilities exist to convert latitude and longitude to locators.  Firstly, commercially available (civil) Global Positioning System (GPS) receivers are commonly able to show Maidenhead locators.  You can then uncover your square by using a GPS and setting it to Maidenhead Coordinates instead of Lat/Long.  You can also plug in your address in any of the on-line map programs and get the Lat/Long and then change them to Maidenhead.  One popular online site which offers grid square conversion is

Hunting Grid Squares on 11m

Most DA-RC QSL cards contain a box/field for operators to mark in their own grid square.  But, what if you have just worked a station and received the QSL card and there is no mention of HIS grid square?  If you are not a subscriber to DX Atlas (See ), then there are several programs that you can get from packet or a bbs to work out what an operator’s square is.  They are GRID.COM, GRID.ZIP, GRIDLOC.ZIP and GRIDX.BAS.  All of these programs do basically the same thing.  They allow you to input a latitude and longitude which will then give you a corresponding grid square.  You can also go the other way and input the grid square and then out comes the latitude and longitude.

Where & how do I get the latitude & longitude of the station I worked?

The short answer is you will have to look in an atlas and figure it out yourself.  The ARRL publishes a World Grid Locator Atlas and this is great if you know a major city near where the station says he lives.  Sometimes, however, you will get a city that is tiny and will not appear on all maps.  In this case, looking up the location of nearby famous landforms, infrastructure and of course other cities and towns, will usually give you the same square.

QSL Field, DA-RC QSL CardOf course, the best thing is to get into the habit of saying “My grid square is…………,  what is YOUR grid square?” Not every eleven metre operator will know his grid square of course but it can save you lots of time just by asking.  If it’s a DA-RC member, they will usually oblige.

As you work more stations, keep track of your grid squares by recording them in your log and in no time at all, you will have your first 100 and earn your DA-RC Century Club award.

For more information on the Maidenhead grid squares concept and its use in the Dx Adventure Radio Club (DA-RC), please contact the HQ Team via the Contact Form on this website