 Amateur radio operators on various retired maritime vessels, such as the destroyer USS "Kidd" and the battleship USS "Texas", regularly use vintage transmitters to communicate with other ship museums for events like Museum Ships Weekend and National Pearl Harbor Remembrance Day.Amplitude modulation (AM) was once the main voice mode in amateur radio before being superseded by Single-sideband modulation (SSB).But AM has recently become a nostalgic specialty interest on the shortwave ham bands.