NDB Radio Navigation, II
NDB stands for Non Directional Beacon. It is a L/MF radio station which transmits a carrier wave with identifier that can be received by an ADF (Automatic Direction Finder) receiver and an indicator in the aircraft to show the direction the station is located. It can be used to determine your own position, as a marker for an ILS procedure, locator for an airway or as backup for the VOR.
If you own an ADF receiver with an extended range you could also receive AM radio stations as a backup or just for your pleasure while flying. As with the VOR page, we discuss operating this device and its technicalities without getting into much detail. Enough to be found elsewhere on that detailed subject.
Eurocontrol published a document containing VOR/DME/ADF radio navigation aids full with tips for pilots.
VOR DME ADF Navigation
Eurocontrol Guidance Notes
