What channel is designated for GMDSS Digital Selective Calling?

The correct answer is Channel 70, which is specifically designated for GMDSS Digital Selective Calling (DSC). This channel is utilized for sending distress alerts, safety messages, and routine calls digitally, enabling vessels to communicate efficiently without continuously monitoring voice frequencies.

Channel 70 operates at a frequency of 156.525 MHz, and it enables vessels to communicate through classified messages while allowing for the automatic monitoring of incoming DSC signals. This capability enhances maritime safety by ensuring that distress alerts are transmitted and received quickly and easily, even amidst other radio traffic.

In contrast, other channels mentioned have different primary functions. Channel 16, for instance, is primarily reserved for distress communication and emergency traffic but does not specifically support DSC, although it can receive DSC alerts and broadcasts. Channel 6, being a working channel, is also not designated for DSC use. Channel 83 is typically used for private communications and other non-urgent maritime messaging. Thus, Channel 70's unique purpose in the GMDSS framework makes it the correct choice for DSC communications.