The Major Grid Boundries in Hawaii One of the key references for Ham Radio are the Maidenhead Grid Locators. It is named after a place in England where the system originates. It is a system of grids across the Earth which are designated by two letters, two numbers and two more letters. The last two letters are often too specific to be of much interest, so most grid squares are designated by just the first two letters and the two numbers.
Grids are two degrees wide and one degree from top to bottom.
The two longitude lines fall on Oahu and the Big Island. The second slices down through Oahu basically running through Pearl City and the tip of Kahuku Point. Eight grids on major land areas. This is important since many VHF contests and awards are based on working a certain number of grid squares. Unlike many Mainland locations, some of our promising grid squares like BL00, BL12 and BL21 are just ocean.