If you’ve bought a VHF radio in the last few years, chances are it has a red istress button on the front. Lift the flap, press and hold the button for five seconds, and details of your vessel, your position, and the fact that you require urgent and immediate assistance are broadcast to the U.S. Coast Guard and anyone else with a DSC-equipped radio within range. The beauty
of the system is that it should summon assistance even if you’re unable to speak.
When you consider that a DSC-equipped VHF can be had for about $150 and
is arguably the single most important piece of safety equipment that you can have
aboard, it sounds like a bargain. However, according to recently published Coast
Guard figures, almost 90 percent of DSC-capable radios aren’t programmed, making
that little red distress button completely useless. Here’s what you need to do.
Two things need to happen for a DSC-VHF radio to work properly. First, it has to
be connected to a GPS; second, the radio needs to be programmed with an MMSI
number. MMSI stands for Maritime Mobile Service Identity and refers to the unique
number assigned to a particular boat.
Connecting your VHF to your chartplotter provides your coordinates to the radio
so they can be transmitted in an emergency. With no GPS hooked up, the position
Can You Hear Me Now?
DSC is one of the best deals in town. Setting up your VHF radio with digital
selective calling is simple, and it could save your life
of the boat must be triangulated from the
transmission by multiple shore stations,
reducing accuracy. Connecting the VHF
to a GPS – such as a chartplotter – isn’t
difficult, but you must follow the instructions that came with your VHF and GPS
to ensure compatibility. This is where
many boaters become
frustrated. In reality, it’s
often a matter of just
connecting a couple of
small wires. However,
if you’re shopping for
a new VHF, manufacturers now offer VHF
sets with GPS built in,
eliminating the need to
connect a GPS.
Once the connec-
Practical Boater COMMUNICATIONS
tions have been made,
the next step is to pro- PH
By Mark Corke
up and using
a DSC radio.
More Than A
Although digital selective calling’s greatest asset is its ability to
summon help in the event of an
emergency, a DSC radio, once programmed with a Maritime Mobile
Service Identity number, can call
other DSC-equipped boats by entering the MMSI of the vessels you wish
to call. Frequently called numbers
can usually be stored in the VHF’s
memory, so much like using speed
dial on a phone, calling a fishing
buddy is as easy as pushing a button.