Re: Smartphone or Tablet Marine Gps
+1 dingbat. I have to agree if you are going to do it right get the right equipment. A cell/smart phone is a good back up but it should not be the main source of your survival.
ssobol - Good input but "you can always tell them your coordinates." Not really. In the time of an emergency there are dozens of things happening all at once. You could have a fire, a sinking boat, 12ft seas or children needing assistance. Taking the time to look at your phone, get the coordinates and contact the CG takes precious time. If one can automate it will increase the chances of survival. However for light none eventful application a cell/smart phone can work just fine.
On thing to keep in mind is that the DCS radio needs to be set up and connected to the GPS source properly for the DSC and Distress functions to work. It is reported that a high percentage of the DSC radios are never set up properly either because people don't know this or don't bother. The actual DSC functions are probably of limited utility for most recreational boaters. DSC basically acts as a phone number for your radio. To use it to talk to someone, you need to know the MMSI number of the radio you want to talk to. Most recreational boaters use their radios in a more informal manner.
The distress function will work if you have GPS connected to the radio without a MMSI number. However, if you have a MMSI number in your distress message they will know who you are. Also, if they know who you are they will try to contact you before launching a rescue to see if it is a false alarm.
For DSC to work you need to register for a MMSI number and program it into the radio. You can get a MMSI number for free for use in the US. If you want one you can use outside the US you need to pay $160.
Once a MMSI number is programmed into a particular radio it cannot be changed except by sending the radio in for repair.
Recreational vessels are not required to have a MMSI number unless they broadcast AIS.
If I was in the situation where I needed to use the distress feature, I would be sure to actually try to talk to someone to see that the information was received. Just because you press the distress button doesn't mean anyone actually got the message. Also, if you can't talk to anyone it might mean that the radio is not working which could also mean that the distress signal did not go out.
In a really dire situation I would have more confidence in a PLB or EPIRB instead of the VHF.
