Which VHF channel is used for Digital Selective Calling (DSC)?

• A. VHF Channel 70
• B. VHF Channel 16
• C. VHF Channel 81A
• D. VHF Channel 13

Answer: (A)

DSC uses a dedicated digital channel on VHF to send automated calls and distress signals. That channel is Channel 70 (156.525 MHz), reserved specifically for DSC traffic so distress, safety, and routine calls can be addressed and acknowledged digitally without crowding the voice channels. After a DSC call is established, operators often switch to a voice channel to continue the conversation.

Channel 16 is the primary voice distress, safety, and calling channel, used for initiating contact by voice rather than DSC data. Channel 13 is used for ship-to-ship safety and navigation communications, typically near harbors, not for DSC. Channel 81A is a data channel for other purposes and not the standard DSC channel. So the DSC-dedicated channel remains Channel 70.