3D COVERAGE MAP / ELEVATION DATA TAB HELP

Enter latitude and longitude in decimal or DMS format, and
the transmitter elevation above the point.

Valid Input:
  Latitude: -90 to 90 degrees
  Longitude: -180 to 180 degrees
  Transmitter Height: 0 m to 20,000 m (0 ft to 65,616 ft)

Features:
  - Get Elevation: Returns sea-level elevation at the point
  - Load 3D Map: Displays 3D terrain coverage visualization
  - Save/Load/Edit coordinate points
  - Zoom control (5 levels: 20-100 sq km)
  - Overlay lighting modes for coverage visualization

Uses the WGS-84 geodetic coordinate system. The 3D coverage
map requires OpenGL support. Coverage overlay shows areas
with line-of-sight visibility (lighter = in range,
darker = out of range).
