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The grid locator doesn’t display accurately

We often hear this comment probably because the map shows an image with the pointer in the ocean/sea.

Expectations by users about locator accuracy are ambitious so here is a graphical representation of locator squares, I used the KH8RRC lookup as an example.

The world is divided into 32,400 two letter grid squares (e.g.AH) covering thousands of square miles.

AH locator.png
When you add the two numbers to the two letter reference the main grid square is sub divided into 100 smaller squares (Total of 324,000 squares in the world) Each of these squares are approximately 70×100 miles

AH45 Locator as provided by FT8 softwareAH45 Locator.png
Adding the two letters after the first 4 characters (AH45PR) sub divides each of the 4-digit squares into 576 sub squares (A total of 18,552,400 sub squares covering the world)) each sub square is approximately 4 miles by 6 miles

AH45PR Locator new.jpg
Adding a further two numbers to the 6 digit reference like AH45pr99 subdivides the 6 digit square so a closer fix can be made on the location.

AH45PR99 Locator new.jpg
This is why you don’t see an exact match to a stations location because with the provided information we don’t know where the station is located within the indicated square so we display the square with the marker in the centre. (sometimes the centre of the square could be in the ocean)

Even given a 12 digit locator, as used by microwave operators, its only possible to get to within a couple of hundred yards of the actual location.

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