Thursday, July 03, 2008
Caribbean NDB Changes
Some interesting NDB changes from the Caribbean for my lowband friends:
"AR" NDB at Pointe A Pitre, Guadaloupe, has been shutdown.
"PTP" NDB at Pointe A Pitre, Guadaloupe, has changed frequency from 300 kHz to 385 kHz.
"FOF" NDB at Fort de France, Martinique, has changed frequency from 314 kHz to 329 kHz.
What is a NDB you ask?
"A Non-directional beacon (NDB) is a radio transmitter at a known location, used as an aviation or marine navigational aid. As the name implies, the signal transmitted does not include inherent directional information, in contrast to newer navigational aids such as VHF omnidirectional range (VOR) and TACAN. NDB signals follow the curvature of the earth, so they can be received at much greater distances at lower altitudes, a major advantage over VOR. However, the NDB signal is affected more by atmospheric conditions, mountainous terrain, coastal refraction and electrical storms, particularly at long range. Even with the advent of VHF omnidirectional range (VOR) systems and Global Positioning System (GPS) navigation, NDBs continue to be the most widely-used radio navigational aid worldwide.
"NDB usage for aviation is standardized by ICAO Annex 10 which specifies that NDBs be operated on a frequency between 190 kHz and 1750 kHz although normally all NDBs in North America operate between 190 kHz and 535 kHz. Each NDB is identified by a one, two, or three-letter Morse code callsign. In Canada, some of the identifiers include numbers. North American NDBs are categorized by power output, with low power rated at less than 50 watts, medium from 50 W to 2,000 W and high being over 2,000 Watts."