About
NBD's, or non-directional beacons, are used for marine and aeronautical navigation and TWEB services. Many airports, public and private, use these for air navigation. They send out a signal in the LF (low frequency) part of the radio spectrum. The continuous signal is used by pilots to direction find a particular location, such as an airport or landing strip. The transmitters usually send their ID in morse code, but some send voice. As of 2020, NDBs have become obsolete and are being phased out at a fast rate due to newer technologies such as GPS. This website is dedicated to these beacons and holding their information for future generations to see, in addition to being a useful utility for finding NDBs that are still broadcasting.
The Decline
The main reason NDBs are disappearing off the air is because of newer technology. GPS can provide more accurate and more convenient location data than simple radio direction-finding. In addition, beacons equiped to transmit voice information have also been made obsolete by interenet services. Many aviation executive bodies around the world have been turning away from their mass networks of NDB's and have been shutting down transmitter sites over the last few years.
As of April 2018, the American FAA had disabled 23 ground-based navaids including NDBs, and plans to shut down more than 300 by 2025. The FAA has no sustaining or acquisition system for NDBs and plans to phase out the current NDBs through attrition, citing decreased pilot reliance on NDBs as more pilots use VHF omnidirectional range (VOR) and GPS navigation.
From Wikipedia
Most beacons in the U.S. are owned by the FAA. States, counties, and citities who operate thier own transmitters have also been deciding to cease operation.
Hunting for Beacons
NBDs are found in the long-wave spectrum. Worldwide, they can be found in the range of 190 to 1750, but in North America, they are found at 190 to 535 kHz. When scanning or listening to beacons, it is best to be far away from the main electric grid and other sources of interference. Night time is the best time to search because signals on these lower frequencies propagate better during this time. Clouds do not cause interference, but nearby lightning can cause 'static crashing', which is heard as a popping sound on your radio. With major storm clouds nearby, it can be hard to hear anything over the popping. Most NDBs only repeat their callsign in morse code. In the United States, the morse code is played at 1020 Hz, and in Canada, it is played at 400 Hz.
Names
In addition to frequencies and morse code ID's, beacons can be identified by names. At one point, it was standard for all U.S. beacons to have a five-letter name. They were usually named after a city, airport person. Because the standard was five letters, the names could get pretty abbreviated, like the MANNS beacon (MF, 372 kHz) in Mansfield, OH. However, some get so abbreviated that the name just turns into gibberish. Such is the case with the CAGUR beacon (YK, 347 kHz) in Yankton, SD. The name is actually short for Chan Gurney, which is the airport name. Later, the five-letter system ended and beacons names could be any length. In my beacon listings, I try to include two names if I find that a beacon has had both types.
Power
Your average beacon is 25 watts. This is the case for nearly all municipal airports and some larger airports. For a long time, the FAA has deemed many beacons as "MHW", meaning less than 50 watts. Despite this seemingly low power, signals can travel hundreds of miles, with the best propagation occurring at night. Larger air terminals with greater trafic tend to have higher power beacons, usually 100 watts or more. As a sign of the decline of NDB's, a lot of these higher power beacons have had thier power turned down. This can cause confusion to those who are used to hearing a high power beacon from a great distance.
Voice Services
ATIS:Automatic Terminal Information Service
AWIS: Automatic Weather Information Service
AWOS: Automated Weather Observation System
ASOS: Automated Surface Observation System
VOLMET: Meteorological Information Broadcast
TWEB: Transcribed Weather Broadcast
TWEB was very popular in Alaska, but all of those stations have been decommissioned. On January 1st, 2020, a huge massacre on all voice beacons was conducted thoughout North America. Today, there are only two voice stations in the US. There used to be many more, but you get the idea. These kind of stations can also be found around the world, but they are in a similar state.
The Information on This Site
Most of the facts and information above come from my own research and my own experience hunting beacons. In addition, William from the DX Info Centre has filled me in on a few things via email conversations. I do not intend for this website to be a professional research article about non-direction beacons, this is mainly a hobby project. I try to keep things as correct as possible because I do want this to be a useful resource for others who are interested in the topic. With that being said, you are welcome to email me if you have spotted a mistake or if you have some new and helpful knowledge that could benefit this site. Also, updating the listings is very time consuming. Since this beacon page is not as high on my priority list as it used to be, there may be significant delay in updating the data.
As for the expansive lists of beacons bellow, I mainly use two sources: LW Radio Beacons (dxinfocentre.com) and AirNav. William's page holds a long list of hundreds of beacons in the US and other countries. He updates the great list every once in a while based on FAA information. I use this as my basis for my lists. I supplement the data with info from AirNav, which sometimes has additional facts.
Contact: George White KF0CCI, [email protected]
