HF Radiotelephone Channels - Complete duplex and simplex channel plan available for download. www.navcen.uscg.gov/marcomms/cgcomms/rtchan.htm
US Coast Guard NAVTEX - Information about worldwide NAVTEX coverage. www.navcen.uscg.gov/marcomms/gmdss/navtex.htm
VHF Marine Radio Channels and Frequencies - U.S. VHF Marine Radio Channels and Frequencies Commandant (G-SCT-2) U.S. Coast Guard www.navcen.uscg.gov/marcomms/vhf.htm
