GMDSS Frequencies and Radio Bands Flashcards
6 cards from real GMDSS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 GMDSS Frequencies and Radio Bands flashcards as text
What is the designated simplex inter-ship safety frequency in VHF?
Answer: Channel 6
VHF Channel 6 (156.3 MHz) is the designated inter-ship safety and SAR coordination frequency used during search and rescue operations.
Which frequency is used for MSI (Maritime Safety Information) HF broadcasts via NBDP (Navtex-like HF)?
Answer: 4209.5 kHz
4209.5 kHz is one of the designated HF NBDP frequencies used for automated broadcast of Maritime Safety Information.
In GMDSS, what frequency must all vessels in sea areas A1 continuously guard for DSC alerts?
Answer: 156.525 MHz (Ch 70)
Vessels operating in GMDSS Sea Area A1 must maintain a continuous DSC watch on VHF Channel 70 (156.525 MHz).
What additional DSC watch frequency is required for vessels in GMDSS sea areas A2?
Answer: 2187.5 kHz MF DSC
Vessels in Sea Area A2 must maintain a DSC watch on 2187.5 kHz (MF DSC) in addition to VHF DSC Ch 70.
AAis (Aeronautical) emergency frequency 121.5 MHz is notable in GMDSS because:
Answer: It is the EPIRB homing frequency used by SAR aircraft
121.5 MHz serves as the EPIRB homing frequency, allowing SAR aircraft and vessels to home in on a distress beacon's location.
What is the purpose of the 2174.5 kHz frequency in GMDSS?
Answer: MF NBDP (telex) distress and safety working frequency
2174.5 kHz is the MF NBDP (narrow-band direct printing/telex) frequency used for distress and safety traffic in GMDSS.
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