IEC 61097-13 Ed. 1.0 en:2003

Specifies the minimum operational and performance requirements, technical characteristics, methods of testing and required test results for INMARSAT F77 ship earth stations (SES), capable of transmitting and receiving distress and safety communications, initiating and receiving distress priority calls and transmitting and receiving general radiocommunications, using radiotelephony (voice), as required within the relevant IMO Regulations.