🔍 Key Concepts

• Radiotelephone (voice) vs. radiotelegraph (Morse/code) distress services • Traditional MF (medium frequency) international distress frequencies used before full GMDSS implementation • Knowing that kHz here refers to older voice distress channels, not VHF Channel 16

💭 Think About

• First separate which of these choices could realistically be a voice distress frequency, not Morse/code • Think about which frequency you’ve most often seen associated with older MF voice distress watchkeeping requirements on ships • Eliminate any options you recognize as primarily associated with non-voice or obsolete services (e.g., classic Morse distress)

✅ Before You Answer

• Confirm which listed frequency was historically designated as the international radiotelephone distress frequency in the MF band • Verify that 500 kHz is famous for a different type of distress communication (not voice radiotelephone) • Check that VHF Channel 16 (156.8 MHz) is not among the choices, so you are dealing with MF kHz voice distress, not VHF