Reference Point
The reference point for calculations of transmitter power density is the prime focus of the Green Bank Telescope (GBT). The location of the GBT prime focus is:
Latitude: 38d 25m 59.2s N (NAD83)
Longitude: 79d 50m 23.4s W (NAD83)
Ground Elevation: 806 Meters or 2644 Feet AMSL (NAVD88)
Height: 139.6 Meters or 458 Feet AGL
