Hi Group

I've heard you had a discussion about AIS for leisure crafts (eg sailboat),
so I have just started "listening" to this news group.

Could you "kick-start" me on the subject?

Thanks
/Boerge

Børge Wedel Müller wrote:

I've heard you had a discussion about AIS for leisure crafts (eg sailboat),
so I have just started "listening" to this news group.

Could you "kick-start" me on the subject?

Good timing. I just installed a Nasa Marine "AIS Radar" on Voyager this
week (see http://www.nasamarine.com/). I don't think they're available
in the States but was in England on business so picked it up there.
Price was 230 pounds, including VAT.

It takes 12 volts, a VHF antenna, and NMEA from the GPS in, and plots
on a radar-like screen the position of all vessels transmitting AIS.
The rule is that all ships over 300 GRT must have AIS.

On Voyager we sail very short-handed so a watch is always a headache. I
have an old Combi Watchman radar detector, but have found that over
half the ships we encounter at sea do not have their sets on (you can
see their antennas not rotating). We use radar sometimes with an alarm
set, but that sucks an awful lot of power. And, it can't tell the
difference between a ship and a squall, and too often there's rain
squalls everywhere, making the alarm feature problematic.

Here in Baltimore harbor the AIS immediately found and plotted two
dozen ships. You can toggle to a specific ship and it shows the
vessel's position, name, MMSI, course, speed and status. The alarm,
when enabled, beeps loudly when there's a ship within a user-specified
range of the yacht.

The gear works great. My biggest complaint: it uses a brain-dead PIC
micro without enough memory to remember all of the info about the ships
it tracks. So when you toggle to a new ship there's a delay - sometimes
a couple of minutes - while it waits for an AIS transmission from the
ship.

The device is rated at 80 milliamps draw, though I measured 130ma.
Still, that's nothing. I'm anxious to try it at sea.

It does need its own VHF antenna - the higher the better the range.
Voyager is a ketch so the antenna lives atop the mizzen.

AIS appears to be a real boon for short-handed watchkeeping.

Jack
www.ganssle.com/jack

On 4 Dec 2005 06:44:44 -0800, "
wrote:


Good timing.

Jack
www.ganssle.com/jack

Thanks for the info and review... on AIS

I went to your web page - very nice and informative -Jacks musings
blog and dual monitors and all.

And your PDF article on USB scopes also worthy although I didnt have
the time to read your 4 books or other 500 articles but the rebuild of
your sail diesel was interesting...

Hey Larry you might be interested in Jacks links www.ganssle.com


MIC

(Mic) wrote in :

Hey Larry you might be interested in Jacks links www.ganssle.com


Thanks, I'll take a look.

Anyone noticing or knowing about AIS fixed obstructions/bouys/etc. being
transmitted from shore stations in their area, please let us all know what
you know...thanks, too!

On Sun, 04 Dec 2005 20:47:03 -0500, Larry wrote:

(Mic) wrote in :

Hey Larry you might be interested in Jacks links www.ganssle.com


Thanks, I'll take a look.

Anyone noticing or knowing about AIS fixed obstructions/bouys/etc. being
transmitted from shore stations in their area, please let us all know what
you know...thanks, too!

http://www.yachtvalhalla.net/projects/ais/ais.htm

"AIS (Automatic Identification System)

The International Maritime Organization has ruled that all vessels of
300 gross tons or greater and all passenger vessels must carry AIS
transponders. These transponders broadcast their own AIS data and
receive it from other vessels. Information such as the vessel
identity (MMSI, vessel name and callsign), position, rate of turn,
course, speed, destination, and cargo is continuously broadcast over
VHF frequencies and displayed on dedicated or integrated navigation
systems. Though these active systems are expensive, there are low
cost, receive only units available that provide, for the small boat
owner, a display of much greater use than radar for these 'big boys'."

Good graphic and images

http://www.yachtvalhalla.net/projects/phone/phone.htm
Satellite Telephone (December 2003)

Mic

On Wed, 07 Dec 2005 19:32:22 GMT, (Mic) wrote:

Though these active systems are expensive, there are low
cost, receive only units available that provide, for the small boat
owner, a display of much greater use than radar for these 'big boys'."

===========================================

The biggest issue for small boats is not seeing the big guys (they
show up easily on RADAR), but being seen. Only an active AIS
transponder can provide that assurance since small boats are easily
overlooked or missed entirely on a large ship's RADAR. As large ships
come to rely more on AIS, and devote more time to monitoring, this
will become even more of a critical issue.

On Wed, 07 Dec 2005 19:32:22 GMT, (Mic) wrote:

On Sun, 04 Dec 2005 20:47:03 -0500, Larry wrote:

(Mic) wrote in :

Hey Larry you might be interested in Jacks links www.ganssle.com


Thanks, I'll take a look.

Anyone noticing or knowing about AIS fixed obstructions/bouys/etc. being
transmitted from shore stations in their area, please let us all know what
you know...thanks, too!

http://www.yachtvalhalla.net/projects/ais/ais.htm

"AIS (Automatic Identification System)


More Links

http://www.sealinks.net/OverviewPage.htm

http://www.sealinks.net/LinksPage.htm
Our Product Brochures (.pdf)
SL161R AIS Receiver Brochure
SL161R Technical Specifications
SL161R Basic Installation Instructions
SL162B AIS Transponder Brochure
SL162B Technical Specifications

http://www.pilotmag.co.uk/
http://www.impahq.org/
http://www.internationalpilots.org/articles.asp

http://ssca.org/sscabb/index.php?act...um=6&topic=769
SSCA Discussion Board —› Underway —› Anyone using AIS?
This is a 2 page thread...worth the read.

" wrote in
oups.com:

Here in Baltimore harbor the AIS immediately found and plotted two
dozen ships.

Is any bureaucratic entity transmitting from shore all the bouys,
obstructions and notice-to-mariners yet? We're way behind on AIS in the
States, how awful. I've talked to a few Coastie techies and I was more
instructional about AIS than I got answers to what CG is doing to get the
fixed obstructions on the air.

On Sun, 04 Dec 2005 20:45:40 -0500, Larry wrote:

Is any bureaucratic entity transmitting from shore all the bouys,
obstructions and notice-to-mariners yet?

========================================

The Navtex broadcasts have much of this. You can receive them on an
ICOM802 with a Pactor, Airmail and a laptop.

Wayne.B wrote in
:

The Navtex broadcasts have much of this. You can receive them on an
ICOM802 with a Pactor, Airmail and a laptop.



SO obsolete plotting manually from some stupid 1930 teletype
transmission.

AIS shore stations operated by someone who keeps up with changes in all
the data in your LOCAL area, so you can notify him, directly, of any
changes to objects that create a safety hazard, broadcast these objects
in the datastream with complete identification texts that open up by just
pointing to them on the AIS display. These objects are graphically
represented as to what they are, their bouy number for instance, color,
etc. to make the radar picture even more informative than just showing
the moving vessels.

CG across the country should already be online with AIS objects in every
port and on every waterway. We'll easily get what little money it takes
to make this happen by NOT writing a new construction contract on that
pretty front gate house the admiral wants to waste the money on.