ABSTRACT
DSC forms a vital sub-system within the GMDSS, being used as the primary alerting system of the MF, HF and VHF terrestrial services. Indeed, the terrestrial elements of GMDSS adopted by the 1998 amendments to the International Convention for SOLAS 1974 are based on the use of DSC for distress and safety communications. As such, any ship or coast station receiving a DSC distress alert becomes aware that an important communication relating to distress will follow on a radiotelephone or radiotelex distress channel/frequency.
