Introduction
Among the many types of marine radios, careful users will find that high-level radios with DSC digital selective calling have a DISTRESS key and a pre-coded MMSI (Maritime Mobile Service Identity) code. When you need to initiate a distress call in an emergency, you must have a pre-set MMSI code to make the call, which facilitates the rescue of the ship in danger by surrounding ships and shore station dispatchers. Of course, if a regular non-fixed ship is used, radios that do not require emergency call functions can skip the input of the 9-digit MMSI ship identification code and perform regular receiving and transmitting operations like regular wireless communication.
Features of MMSI Code
The MMSI code is a 9-digit numerical code with specific meanings. For users, it can only be programmed once and cannot be changed, so it must be carefully coded by the using unit according to the usage of the unit’s ships, and it cannot be changed by yourself after confirmation. Following the product manual step by step, you can complete the setting and confirmation of the MMSI code. Here is a reference for the operation interface and confirmation reminder of an IC-M423 marine radio.
Emergency Distress Rescue
If the ship is in serious danger during navigation and needs emergency assistance, you can lift the protective cover of the distress key, press and hold the distress key for more than 3 seconds, and the device will automatically start the distress transmission alarm, repeating every 3.5-4.5 minutes until a response message is received, a conversation is established, or the call is cancelled.
