Which of the following frequencies has NOT...

🔍 Key Concepts

• GMDSS (Global Maritime Distress and Safety System) on-scene and SAR (Search and Rescue) working frequencies • The traditional international distress frequency 2182.0 kHz and what type of emissions are permitted on it • The difference between radiotelephony and SITOR/NBDP (narrow-band direct-printing) services

💭 Think About

• Look at each option and ask: is this a commonly recognized voice (radiotelephony) distress, urgency, or safety frequency used for on-scene coordination? • Consider whether data/telex-style modes are allowed or normally assigned exactly on a radiotelephony distress frequency like 2182.0 kHz. • Think about which of the listed methods you have specifically seen in GMDSS tables as ON-SCENE or SAR working channels, not just as general distress or calling frequencies.

✅ Before You Answer

• Verify in your study materials which frequencies are explicitly listed as on-scene/SAR voice working frequencies (pay attention to mode: radiotelephony vs. NBDP). • Check what kind of transmissions are permitted on 2182.0 kHz under distress regulations: is it reserved for voice only, or also for SITOR/NBDP? • Confirm that VHF Ch-16 and 4125.0 kHz are recognized for distress/urgency/safety and on-scene coordination, then compare how 2182.0 kHz is used and by which modes.

Which of the following frequencies has NOT been designated for GMDSS “On-scene” or SAR communications?

VHF Ch-16

MF radiotelephony on 2182.0 kHz

SITOR ( NBDP ) on 2182.0 kHz

HF radiotelephony on 4125.0 kHz

🔍 Key Concepts

💭 Think About

✅ Before You Answer