Home
Home
[ Geotables ]
[ About Beam Headings ] [ About Declination ]
AC5JW Geolocation Tables give context for the location of aerials, callsigns, jurisdiction, QTH, repeater site, residence, shack, and towers. Positioning is given in decimal degrees, Maidenhead locator grid, and altitude. While efforts are made to vet all listed positions, accuracy cannot be guaranteed due to conficting references, limited or outdated information, and time constraints. Points without a call sign receive an arbitrary unique label within Geotables. Such labels and call signs are also used in the AC5JW Beam Headings tables.
Already familiar to aircrews and mariners, the knowledge of geolocation (combined with beam headings and distance) can produce the current position of fixed, mobile, and portable radio amateurs. Beyond aiding someone in distress and chasing grid squares, geolocation is useful for establishing a radio beam heading, proper positioning of aerials, and resolving radio interference. It also helps with determining the applicable time zone for a point and the distance between points.
Geolocation is critical for studying distance and the terrain profile between two points. It helps to identify terrain obstacles that block direct-path and line-of-sight communications. Finally, the awareness of geolocation helps us to analyze, exploit, and predict alternate paths of radio communication apart from a direct route.
The practice of geolocation by radio amateurs is an important skill that may be called upon at any time. Combining geolocation with radio is necessary for determining the location of people needing assistance and for determining who is near enough to render the proper aid. It is best to develop geolocation skills before an emergency in order to avoid mistakes. Until an emergency occurs, chasing grid squares and becoming informed on locations of communicators over radio are great examples of ways to practice this skill and will help you to build and demonstrate your preparedness.
Declination is given in magnetic degrees and includes a direction east or west of true north. See About Declination for more details on how to use this information. All geolocation and derivative tables are under revision to provide a recent declination using the World Magnetic Model as a transition away from the International Geomagnetic Reference Field .
Altitude above Sea Level (ASL) is given in meters and feet. ASL is the value for the terrain at ground level, not to be confused with other values above ground level (AGL). Tower heights and structure heights are not provided in this listing of terrain altitudes.
