Aug 4, 2026 – “What are Grid Squares?”

Good evening. This is W1UT and tonight’s topic will about “Grid Squares”.

Back in the 1980s while living in VT, I got interested in long haul simplex communications on 2m’s. All I had at the time was an old Kenwood TS9000 all band 2m radio that ran 10W of power out. This was typical for radios from that era. I bought an 80W amplifier and a multi-element Cushcraft yagi that I installed on my tower. For a number of years I had fun working stations regularly 200-300 miles away without relying on a repeater. At times I was able to take advantage of special weather conditions called tropospheric ducting and work stations down in gulf region and well into the midwest. It was fun but I ended up losing interest as it seemed that I always was working the same stations. I do not know how popular SSB or CW here in the west is these days is as there is much more equipment available with all mode capability. Most hams in those days started using something called Grid Squares as a locator.

Back in 1980 in a town outside of London at a meeting of European VHF managers conceived of a maidenhead locator system called grid squares. A grid square measures 1° latitude by 2° longitude which measures approximately 70 x 100 miles in the lower 48 states in the US. They came up with a designator consisting of two letters (the field) and two numbers (the square) representing a location on the surface of the earth. This is a pretty broad area, so two additional more precise locators were added to the four character grid square. This means a six character grid square measures a location 2.5 mins latitude by 5 mins longitude or roughly 3 x 4 miles in the continental US.

The actual size of a grid square depends on the particular location, as the 1° of longitude represents different distances at different latitudes; longitude lines are closer together at the Earth's poles than at the equator. The first step, then, is finding your latitude and longitude as accurately and precisely as you can to obtain you grid square.

For example the 4 digit grid square for Salt Lake city is DN40 and an example 6 digit grid square location is DN40bs. There are on-line calculators available to help calculate your grid square location based on longitude and latitude or city name anywhere on the earth’s surface. One easy way to find your Lat/Long is to use Google Earth. You can also use a GPS receiver.

Collecting grid squares is often used during VHF/UHF contests and even for those doing moon bounce communications. With the growth of digital modes the collection of grid squares is likely also been added to a ham’s quiver of tools. All of my experience predated any digital modes of operation that I had any access to. Logging tools these days have added grid square locators to their databases. Some people try to collect all grid squares in the US or other parts of the world. As you can imagine this would be a significant challenge – even greater than collecting stations located in all counties of the country. There are many grid squares and even counties in extremely rural areas of the country where no hams reside. Thus making contact with these remote areas requires someone operating mobile while passing through.

For those using HF, grid squares seem to be rarely used. Why this is the case I do not know. Anyway, if you do get into long haul VHF or UHF communications, you will likely run into this concept of grid squares.