U.S. Coast Guard radio stations

The United States Coast Guard maintains radio stations for communication between Coast Guard units, Coast Guard units and other government entities, and Coast Guard units and the general public. Most communications take place on the VHF marine bands. For long-range communications with aircraft, Coast Guard stations use shortwave single-sideband communications. Weather and safety of navigation forecasts involve facsimile as well as other modes over shortwave and mediumwave transmissions.

According to the NTIA, the Coast Guard is the seventh-biggest user of radio spectrum in the United States. The U.S. Coast Guard maintains a network of VHF radio stations at its shore stations and on cutters and boats, as well as stations of the U.S. Coast Guard Auxiliary. In addition, the Coast Guard maintains a chain of high frequency (HF) and medium frequency (MF) radio stations that provide communications in the Atlantic and Pacific oceans, the Gulf of Mexico, and the Caribbean Sea. Coast Guard VHF Radio stations are currently being upgraded through the Rescue 21 program to meet the US obligations under the Global Maritime Distress Safety System.

The first Coast Guard shore stations were established after 1924, when the Coast Guard's mission expanded. The first shore station was at Rockaway Point Coast Guard Station, located at Fort Tilden, New York; and the network expanded to Nahant, Massachusetts; New London, Connecticut; Cape May, New Jersey; Cape Henry, Virginia (with the call sign NMN); Fernandina, Florida; Fort Lauderdale, Florida; Mobile, Alabama; San Francisco, California; San Pedro, California; Port Angeles, Washington; and Anacortes, Washington in the 1930s.

The network expanded even further in the 1940s, adding radio station NMH in Washington, D.C, among others. However, in the 1970s, the increasing use of automation caused the number of stations to contract. In 1976, for example, NMN (then at Communication Station (COMMSTA) Portsmouth) assumed the duties of NMH in Washington, and took over remote operations from Miami in 1993, Boston (NMF) in 1996, and New Orleans in 1998.

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