Again, to make manual calculations from degrees and minutes easier, 24 was chosen as the base number, giving these subsquares dimensions of 2.5' of latitude by 5' of longitude. These are encoded into a second pair of letters, often (but not always) presented in lowercase. Each of these squares represents 1° of latitude by 2° of longitude.įor additional precision, each square can optionally be sub-divided further, into subsquares. This is where the alternative name "grid squares" comes from. The second pair of numbers, called a square and placed after the first pair of letters, uses a base number of 10, and is encoded using the digits "0" to "9". Description of the system įields are divided into 100 squares each. Īt the 1999 IARU Conference in Lillehammer it was decided that the latitude and longitude to be used as a reference for the determining of locators should be based on the World Geodetic System 1984 (WGS-84). That devised by Dr. John Morris (G4ANB) was deemed to be the best. īy the time of their April 1980 meeting, in Maidenhead, England, the VHF Working Group had received twenty different proposals to replace the QRA locator grid. The QRA locator system was limited to describing European coordinates, by the mid-1970s there was growing need for a global locator system. To facilitate this, following the growth of the sport in the 1950s, the German QRA locator system was adopted in 1959. Īmateur radio contests on VHF and UHF are often scored based on the distance of contacts, typically 1 point per kilometre, so there is a need for amateurs to exchange their locations over the air. John Morris G4ANB originally devised the system and it was adopted at a meeting of the IARU VHF Working Group in Maidenhead, England in 1980. The only abbreviation recommended to indicate a Maidenhead reference in Morse code and radio teleprinter transmission was LOC, as in LOC KN28LH. Use of the terms QTH locator and QRA locator was initially discouraged, as it caused confusion with the older QRA locator system. Maidenhead locators are also commonly referred to as QTH locators, grid locators or grid squares, although the "squares" are distorted on any non- equirectangular cartographic projection. The Maidenhead Locator System can describe locations anywhere in the world. Its purpose is to be concise, accurate, and robust in the face of interference and other adverse transmission conditions. QTH Locator and IARU Locator) is a geocode system used by amateur radio operators to succinctly describe their geographic coordinates, which replaced the deprecated QRA locator, which was limited to European contacts. Geocode system used worldwide by radio amateurs
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. Archives
January 2023
Categories |