🔍 Key Concepts

• GMDSS DSC call priorities (Distress, Urgency, Safety, Routine) and when to use each • Difference between calling MMSI (who you are calling) and own-ship MMSI (who you are) in a selective call • Meaning of emission designators J3E, J2B, F1B in the context of radiotelephone vs telex/DSC

💭 Think About

• Is a company business conversation considered distress, urgency, safety, or routine under GMDSS rules? • In a normal DSC call to another ship for voice communications, whose MMSI must you enter in the ‘called station’ field? • For a DSC call that is intended to set up a voice conversation on another frequency, which emission type is associated with normal radiotelephone voice communications on MF/HF?

✅ Before You Answer

• Verify that the priority level matches the seriousness of "important company business" under GMDSS definitions. • Check which MMSI must be entered in a selective call when you want to reach another vessel (own MMSI vs other vessel’s MMSI). • Confirm which emission designator is normally used for voice radiotelephone (as opposed to DSC signaling or telex).