🔍 Key Concepts

• SSB (Single Sideband) voice vs. data/telex modes on MF/HF maritime radio • Differences between J3E voice, DSC (Digital Selective Calling), and ARQ/FEC telex services • How paired ship/coast frequencies are arranged in MF/HF bands for routine communications

💭 Think About

• Ask yourself: When you look at MF/HF marine frequency tables, which type of communication most often shows a ship frequency paired with a separate coast frequency? • Which emission designator (J3E, DSC, ARQ, FEC) is primarily associated with normal voice radiotelephone calls to a coast station? • Which of these services (voice, DSC, ARQ, FEC) usually uses specific DSC calling channels or NBDP/telex channels rather than generic paired voice channels?

✅ Before You Answer

• Identify which choice corresponds to standard voice SSB radiotelephone operation. • Confirm which services (DSC, ARQ, FEC) are associated with digital/telex rather than analog voice. • Check MF/HF marine band charts to see which mode most often appears with paired ship/coast frequencies.