Kurt Schwehr, UNH Professor and author of Kurt’s weblog point us to this quick tip;
6.10 Making a DSC Call (In map mode) To make a DSC call, the unit must be connected to a SimNet compatible DSC VHF radio. . In Display Mode highlight a vessel icon then press and hold the HOME/DSC key, the AI50 will format a Routine Individual DSC call. A "Creating DSC Call" window opens showing the MMSI number and name of the vessel you intend to call. . If this is correct and you wish to continue, press Ret MENU or > to send the call. The "Routine DSC Call" window opens confirming that the call has been created and sent to the VHF radio.
Read the full post HERE.