This has been a great thread and I applaud John and the other contributors for providing valuable information....
My favorites DSC commands are:
Position Reports - Most DSC Radios are connected to your NEMA 0183, which not only obtains the Lat/Long for other boats, but can display other boats on your chart plotter when polled. This allows the Lat/Long of the boat you requested the position report from to appear on most newer (ten years or less) Chart Plotters.
It goes like this... Request a Position Report from another boat using DSC; Other Boat Acknowledges the DSC Call, which returns the Lat/Long to your boat's radio
; The position shows up on your Chart Plotter, in my Raymarine
E-120 it shows as a RED "X"
GROUPS: If you are a RACE
COMMITTEE or RALLY LEADER or just traveling with a group of boats - You can pre-program all the participating boats into your VHF. Then make a Group. This will allow you to either call ALL THE BOATS to a working channel or find out where they are at the push of a button.
TRAFFIC - Most Commercial Vessels, especially in Vessel Traffic Services (VTS) Zones are NOT REQUIRED TO MONITOR
CHANNEL 16. This frustrates many recreation boat skippers when Commercial Vessels don't answer their hail on Channel 16.
For a list of VTS Zones go here:
COMMERCIAL VESSELS are required to have an active Watch Stander monitoring DSC (GMDSS) or a passive audible alarm
that sounds on the bridge when a DSC call is received.
So by using AIS
you can find the ship's MMSI number and send a DSC Call to them or use an ALL CALL, which will sound the ships alarm
and require the Watch Standers to listen to you.
Finally, for routine/non-distress calls, you can pre-program you local USCG Stations into your VHF/SSB:
Corpus Christi 003669916
Delaware Bay 003669905
Humboldt Bay 003669909
Los Angeles/Long Beach 003669912
North Bend 003669911
Northern New England
Port Angeles 003669904
Southeastern New England
St. Petersburg 003669917
All USCG coast stations 003669999
(List Obtained from Power & Motor
Yacht Magazine: USCG Sector MMSI numbers