The Radio Navigational Aids (NGA Pub. 117) publication contains a detailed list of selected worldwide radio stations that provide services to the navigator. The publication is divided into chapters according to the nature of the service provided. Services include RDF and Radar stations; stations broadcasting Navigational Warnings, time signals or medical advice; communication traffic for distress, emergency and safety, including GMDSS; and long range navigational aids. It also contains chapters describing procedures of the AMVER System, and the interim emergency procedures and communication instructions to be followed by U.S merchant vessels in times of national crisis.
The publication is available in its entirety on the Web site, in PDF format. Certain portions of the publication are also available via query to the on-line database.