As I read more about Armateur Radio, am beginning to be more aware of major wireless transmission sites around me. One of such is the Ngong GV 115.9 VOR DME.
This is a huge circular beacon located on your way up to Ngong Hills just as you descend the second hill past the wind turbines. This equipment is is fenced and its very important for pilots as they navigate towards JKIA Airport. Its also a Distance Measuring Equipment (DME)
Located at Lat/Lon: -1.396590, 36.637901 , the Very High Frequency (VHF) Omni-Directional Range (VOR) is is a type of short-range radio navigation system for aircraft, enabling aircraft with a receiving unit to determine its position and stay on course by receiving radio signals transmitted by a network of fixed ground radio beacons. It uses frequencies in the very high frequency (VHF) band from 108.00 to 117.95 MHz. The Ngong VOR transmits at 115.9Mhz hence the name.
Developed in the United States beginning in 1937 and deployed by 1946, VOR is the standard air navigational system in the world,used by both commercial and general aviation.
VOR stations are fairly short range: the signals are line of sight between transmitter and receiver and are useful for up to 200 miles. Each station broadcasts a VHF radio composite signal including the navigation signal, station's identifier and voice, if so equipped. The navigation signal allows the airborne receiving equipment to determine a bearing from the station to the aircraft (direction from the VOR station in relation to Magnetic North). The station's identifier is typically a three-letter string in Morse code.
Thats all for today. If you are interested in such things, you can join the Radio Society of Kenya and learn more. Click here for more info.