The Maidenhead Locator system

What use is an F-call? One of the innocuous questions you are asked during a contact is: "What is your QTH?" or: "Where are you?". Often this is followed by a whole story about a goat track and so many kilometres away from some large land-mark. If you're dealing with an experienced operator, they'll simplify that to something like: 10km North East of Tokyo. Often that's more than accurate enough, but how do you communicate a more accurate location? In this age of GPS, we've all come to know that you can express any location on earth with two numbers, a latitude and a longitude. For example, the main 2m repeater in Perth, VK6RAP is located at 32 degrees, 6 minutes and 4 seconds South, 116 degrees, 3 minutes East, or digitally, -32.100054,116.051551. That's a right royal mouthful. We could improve on that by using a different system of indicating a location. We could use something called a maidenhead locator. For VK6RAP, the locator grid square is OF87av. I'll say that again, OF87av. That's it. The whole location. Now to be fair, I should point out that the maidenhead locator I just told you is in fact a box. Any two points in a box are less than 12km apart, so that's pretty high accuracy for so few characters. We could add another couple of letters and increase the accuracy to a couple of meters, OF87AV66EA is 10 characters, same accuracy as the GPS location I gave earlier, except that was 20 characters and that's not counting south or east. In typical use, we use 6 characters for more than enough accuracy for most amateur purposes. It's pretty straight forward, break the planet down into squares, allocate a letter to each grid, break that square down, and so on. If you want the full detail on this, have a look at Wikipedia, it's all there in full glorious detail, including some example code to write your own software to do conversions. Invented in parallel by John G4ANB and Folke SM5AGM, the Maidenhead Locator System was adopted by the IARU Region 1 in 1982 and started use on January 1st, 1985. We might have been doing Amateur Radio for over a hundred years, but we're still inventing things much more recently. I'm Onno VK6FLAB, currently located at OF78wc