Subelement C: Equipment Operations— Topic 14: VHF Channel Selection
Question 1-14C3
Element 1 (MROP)Which VHF channel is used only for digital selective calling?
Explanation
Channel 70 is specifically and exclusively allocated for Digital Selective Calling (DSC) on VHF marine radios. DSC is a non-voice, digital signaling system designed for transmitting distress alerts, urgent calls, safety messages, and routine calls to specific stations or groups of stations. Its dedicated use ensures rapid and reliable digital communication without interference from voice traffic.
In contrast:
* **Channel 16** is the international voice calling and distress frequency, continuously monitored for urgent voice communications.
* **Channel 22A** is primarily used for public correspondence and U.S. Coast Guard safety broadcasts, often after initial voice contact on Channel 16.
* **Channel 6** is designated for intership (ship-to-ship) safety communications via voice.
These other channels serve various voice communication purposes, unlike Channel 70, which is reserved *only* for digital selective calling.
Related Questions
1-14C1 What channel must VHF-FM-equipped vessels monitor at all times when the vessel is at sea?1-14C2 What is the aircraft frequency and emission used for distress communications?1-14C4 Which channel is utilized for the required bridge-to-bridge watch?1-14C5 Which channel would most likely be used for routine ship-to-ship voice traffic?1-14C6 What channel would you use to place a call to a shore telephone?