The system only works if the radio is installed properly. The vessel has to
have a registered MMSI number which is programmed into the radio. The radio
has to have a NEMA input for it to have position info.

Press the distress button without those and you get allot of noise and no
info.

Check the web for "GMDSS". The A3 terminal installation which I recently
completed cost over $36K. This was for an ocean going vessel.

The US is way far behind the power curve when it comes to safety monitoring.

As for your question, I know the Furuno radios will listen on both 16 and
70. They should, they cost us enough.

Following from the ICOM web site:

Built-in DSC capability that meets U.S.C.G. SC-101
The DSC watch function monitors Ch 70, while receiving another channel. It
allows you to send a formatted distress message in an emergency. The
position request function indicates a caller's position. Up to 30 DSC IDs
are memorized.

Andy K.
"JAD" wrote in message
...
Anyone on the upper Chesapeake, Sunday, (with a DSC VHF) probably listened
to this one........

Three DSC "DISTRESS" alerts were transmitted. One around 8:15 AM, and
two,
about 5-10 minutes apart, around 2:30 PM (EDT.) I copied the two in the
afternoon and wrote down the MMSI (same both times,)....figuring that the
Coast Guard had received it as well. JESUS....if you've never heard
one...the alarm signal (from the Icom 402) is LOUD and obnoxious! It'll
get
your attention! NO position information accompanied these receptions on
my
radio.

After the second one...I hear a skipper call CG group Baltimore with a
question about the strange alarm he has received (he hasn't a clue.) He
reads the display to the Coast Guard...who shakily explains to the guy
what
he has received (they.....the COAST GUARD....acted like they had NOT
RECEIVED IT AT ALL!) Other boaters chime in with addn'l information about
the same MMSI distress they received in the morning.

About an hour later...the CG marine broadcast comes out, describing the
three distress transmissions.....TWO possible boat names, and a general
vicinity in which they were believed to be in (Rock Hall....if anyone's
interested.) I assume they were using the boat in questions home port....

I hope that everything turned out OK....I would LIKE to think that if
someone lifted that red cover....they MEANT it.

If NOT....there are certainly no ANONYMOUS DSC "maydays"..........someone
will get warned....I hope.....

My question.....I could not get my Icom 402 to reliably receive PRIVATE
DSC
transmissions without placing channel 70 in a scan list, or parking the
radio right on 70. Perhaps there were other factors
involved......but......
Isn't the radio supposed to "listen" to 70 at all times? (manual does not
even scratch the surface.......) My pal and I were right next to one
another playing with the private selective call....perhaps we were too
close.... Anyway...it's comforting to know that it received the distress
alarm......

The DISTRESS alerts were received in my normal operating mode......DUAL
WATCH 16 and 22. I have received severe weather alerts in this mode as
well.

I SUPPOSE that Coast Guard does not have DSC distress capability
everywhere
yet...just be aware!

Joe