How to fly an NDB
NDB
An Non Directional Beacon is comprised of an omni-directional Vertically polarised antenna at a known stationary location coupled to a Medium to Low Frequency Transmitter that has an amplitude modulated identification of one, two or three-letter Morse Code callsign. In Australia they use the three-letter Airport Code.
The NDB is described in ICAO Annex 10 that specifies that NDBs operate between 190 kHz and 1750 Khz.