- - All VHF
radio models introduced since year 2000 are required to have DSC
- Digital Selective Calling - installed. The "red button" is the DSC Distress
button which broadcasts an ear-splitting alarm
in All the surrounding vessels with DSC equipped radios within range of your radio transmitter. In a "Distress" situation and you are guarding VHF Ch16 all the other ship's radios will be reset to your channel 16 and the alarm
sounds. Obviously if the radios are turned off this will not happen. You then have to initiate a transmission stating your vessel name, and nature of distress. Also your DSC ship's Identity number will be displayed on all the receiving radios. If you have a GPS
hooked into your DSC radio the lat/long of your vessel will also be displayed. The USCG entered your ID number into their computer and called up your registration
information which is how they knew your boat
It is imperative that you initiate a broadcast stating your vessel and nature of distress or say - "sorry, hit the wrong button - we are not in distress." Otherwise some vessels may turn to your lat/long to provide assistance thinking your are disabled, in peril and cannot reply.
The DSC function can also be used as a "private telephone" connection to your friends who also have DSC radios. You program in their Ship's ID from block 10 of their USA Ships Radio License
into your DSC library in the radio with a "name". They do likewise. Then you set your radio to a channel you wish to talk on (obviously not channel 16) and select DSC "Call" and select their "name". Press the "call" button again and your friend's radio (if turned on) will re-channelize to your channel automatically and sound a "telephone ringing" sound. You then can talk to them. This feature is really great because you avoid having to make blind calls on the local cruisers net frequency. And especially where there isn't a net it is great. DSC radios can operate just like your telephone's speed dial at home.
- - Finally, the DSC "Distress" is very important in the Bahamas
as Channel 16 is used there as local business advertising and booking channel and channel 68 is the normal Cruiser calling channel. With one radio and underway, you are supposed to guard Ch16 - but in the Bahamas
- nobody is listening, they are all on Ch 68. The DSC "Distress" sets off all radios within range and changes their channels back to Ch16 where they can receive your Distress call.