What is DSC?
Digital selective calling (DSC) has been introduced on VHF, MF and HF maritime radios as part of theGMDSS. DSC is primarily intended to initiate ship/ship, ship/shore, and shore/ship radiotelephone and MF/HF radiotelex calls. DSC calls can also be made to individual ships or groups of ships. DSC distress alerts, which consist of a preformatted distress message, are used to initiate emergency communications with ships and rescue coordination centres. Fully implemented, DSC eliminates the need for persons on a ship’s bridge or on shore to continuously guard radio receivers on voice radio channels used for distress, safety and calling, including VHF channel 16 (156.8 MHz) and 2182 kHz. A listening watch aboard GMDSS-equipped ships is scheduled to end on 2182 kHz on 1 February 1999, and on VHF channel 6 on 1 February 2005.