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DSC Testing

The following procedures were adapted from the International Telecommunications Union, Radiocommunications Study Group Recommendation M.541, Operational Procedures for the use of Digital Selective-Calling (DSC) Equipment in the Maritime Mobile Service.

Operating procedures may vary somewhat among different radios, depending upon how the radio is designed, how the radio's software is configured, and how the DSC processor is connected to the radio transceiver.

Testing on the exclusive DSC distress and safety calling frequency 2 187.5 kHz should be avoided as far as possible by using other methods.

NOTE - The USCG no longer monitors 2 MHz

Test transmissions on VHF DSC calling channel 70 should be made to another VHF DSC radio by using a routine individual call to their Maritime Mobile Service Identity (MMSI).

For VHF DSC radios equipped with the Test Call feature, test transmissions should be made to the US Coast Guard MMSI 003669999 to receive an automated VHF DSC test response. You must use the “Test Call” category of your radio because “Individual” category  calls to this address will not receive an automated response. For older radios not having a test call capability, testing can only be performed by using a routine individual call to their Maritime Mobile Service Indentity (MMSI).

UNDER NO CIRCUMSTANCES SHALL A DSC DISTRESS ALERT BE SENT TO TEST YOUR RADIO. IT IS A VIOLATION OF THE RULES AND CAN RESULT IN HEAVY FINES.

Please consult your owner's manual for the proper operation.