Thanks for the correction Peter.
You're right it should have spelled Argos instead of Argo.
The 1.5 nautical mile range accuracy is not all that bad when you are at
sea. However for coastal navigation when you are crossing shipping lanes in
the Bay of Fundy when the fog gets very thick it is not too good. Here the
coast guards are using DGPS on the coast. I do not know how far the land
correction bases can send their signals to validate and correct a GPS
position? The same thing would apply to the WAAS. My old Loran is still
functioning well and when need it I use it to validate my GPS position or
back up.

"Peter" wrote in message
oups.com...

It's ARGOS. I use it and in essence you're correct but what the
satellites see is a function of the transmitter. Basically you can send
a data packet, what's in that data packet is up to you. We have some
ocea buoys with GPS and other instrments attached.

You can triangulate a transmitter location from the sat passes but the
accuracy is in the 1.5 nautical mile range, not the sub 50m range with
GPS.

PDW

wrote:
The other emergency device that the around the world racing sailors are
using is the French Argo system.
This system was primary designed and indented for the French Military.
It
uses satellites to receives signal from the Argo buoys locate on vessels
and then shows the position on a digital computer screen. This way they
can
track down the position of the racing sailboats at all time and advise of
alternative route to avoid hurricane and storms or just giving updates on
the race. This Argo system is not public and requires permission to use.
Today, if you're looking for audio entrainment while awaiting rescue or
just
sailing the new Sat/radio could be a good thing to have on board.

"chuck" wrote in message
...
wrote:
The fade today for coastal navigation is the DSC (Digital Selective
Calling).
This new breed of VHF is connected to a GPS and has a distinctive
signature.
In order to make use of this DSC you have to register it with the
coast
guard. They logged in your signature, call sign, boat description,
navigational equipment, emergency and survival gears. Then the
information is programmed into their data bank. As I witnessed, when
you call the coast guard, traffic and other vessel with the proper
equipment the name of your boat with its position appears on the their
computer/digital radar system. This way when your are in distress and
use your DSC they know your GPS position, the name of your boat and
monitor your position. When you are outside of the coast guard radio
range some people are using sat/phone and EPIRB. Last week a 36 foot
sailboat was rescued by the US guard at approx 200 NM from the coast
of
Nantucket.

"purple_stars" wrote in message
ups.com...
hi again folks,

i'm curious what VHF you would suggest for emergencies, the one
you're
going to be listening in on when your floating in the middle of the
ocean next to your EPIRB after tragedy has struck. i'm thinking of a
radio that you keep with you at all times when on deck, the one that
never leaves your side.




I'm not sure you need to be talking to people while you're floating
next
to your EPIRB! You want to be rescued. If the EPIRB is working, they
will
know where you are. If it is dark, you might wish you had a flare to
help
them. But what are you going to tell them on the VHF? You can't just
say
you're 20 yards south of a used car lot or something.

And what would you listen to? The weather?

Save the VHF and bring some water and food instead!

Others will see this situation differently, I'm sure.

Good luck.

Chuck

wrote:
Thanks for the correction Peter.
You're right it should have spelled Argos instead of Argo.
The 1.5 nautical mile range accuracy is not all that bad when you are at
sea.

I was thinking of it from a safety POV. Having looked for small objects
in the sea quite frequently when recoveriing released moorings,
drifting buoys etc fitted with transmitters, 1.5nm still leaves a lotta
water if you're waiting on rescue. Having said that, it's a hell of a
lot better than 'somewhere in the Southern Ocean...'.

Given the cost of EPIRB's I think they're hard to beat WRT rescue
options. I don't think much of a VHF, it's only going to do you some
good if either the rescuer is within its limited range or you're a
coastal sailor, in which case a waterproof cellphone & GPS would be a
lot more useful.

PDW