🔍 Key Concepts

• GMDSS survival craft portable VHF requirements under SOLAS/IMO performance standards • Difference between radiotelephony channels (voice) and DSC channel 70 (digital selective calling) • Why survival craft equipment needs to be watertight and have an integral/permanently-affixed antenna

💭 Think About

• Which VHF channels are used for voice distress and safety versus digital calling only? Match that with the word radiotelephony in the question. • Think about realistic power levels for a battery-powered handheld survival craft radio versus a fixed ship’s VHF set with 25 W. • Ask yourself which features are essential for a small portable unit in a life raft: antenna type, waterproofing, and channel capability.

✅ Before You Answer

• Verify which channel is used only for DSC (no voice) – should that appear in a purely radiotelephony requirement? • Check SOLAS/IMO requirements for survival craft VHFs: do they specify Ch-16 only, or multiple channels (like Ch-13 or Ch-70), or something else? • Look at each option and eliminate any that have an obviously unrealistic power level for a handheld survival craft radio or that focus on a channel used for digital, not voice, distress.