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.

Just sailed up from Singapore to Langkawi via the Melaka Strait with
AIS running and found no buoys transmitting AIS data. Several base
stations are on the way but that is all.
Am running SR161 that gives a range of about 14 miles with the antennae
on top of the mizzen.
A very useful tool. Used it with the demo version of AIS-yacht which I
have found to be the most responsive and easiest to use and read.
Tony

"Lyn & Tony" wrote in
oups.com:

Several base
stations are on the way but that is all.


I think there are some misconceptions that to make a bouy show up on
everyone's AIS it needs to have a transmitter on it. This just isn't true.
ONE shore station with a tall tower can provide the AIS users with every
bouy, every obstruction or any other type of warning from its data stream.
It doesn't matter where its antenna is. This ISN'T some kind of radar
system, it just looks that way on the display. To show up, any object
needs data transmitted in range of your receiver from anyplace. The data,
not the transmitter's location, determines where the object is displayed.

Larry, true, this is one method of transmitting AIS data for floating objects. As far as buoys are concerned, AIS provides the possibility to allow them to transmit themselves or remotely from a basestation. Self-transmitting is normally used when environmental data is also transmitted.

I quote from the AIS specifications:
"There are three categories of Aids to Navigation in the AIS system:

Real AtoN: The AtoN is equipped with an AIS Station designed to generate
the appropriate AIS messages using local data from the aid and transmitting it via VHF.

Synthetic AtoN: The AIS message for the AtoN is transmitted from another
location (normally a base station) and the AtoN is physically located at the position given in the
AIS message.

Virtual AtoN:The AIS message is an aids to navigation message but no real aid exists at
the location indicated in the AIS message.


Holger

Holger wrote in
:

Self-transmitting is normally used when environmental data is also
transmitted.


Oh, wouldn't THAT be nice if all the NOAA offshore bouys and fixed stations
transmitted their data on AIS.....so you could see live how the wind and
waves are doing up ahead.

Other than realtime data, I see no reason to risk a radio system on a bouy.

"Børge Wedel Müller" wrote...
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


AIS and DSC are the new technologies for receiving
position reports of other boats in your vicinity.

Digital Selective Calling (DSC) is on marine VHF channel 70 (156.525 MHz)
Automatic Identification System (AIS) broadcasts are on two VHF marine
channels 87 (161.975 MHz) & channel 88 (162.025 MHz).


Here is a link to a popular AIS receiver:

http://www.nasamarine.com/AIS/AISENGINE.html

Here are some web pages that further describe AIS and DSC

http://www.navcen.uscg.gov/marcomms/gmdss/dsc.htm
http://www.navcen.uscg.gov/enav/ais/default.htm
http://www.sailmag.com/05feellison.qrk.pdf
http://www.amcom.nl/marine/icom_ic_m421.htm

If you want to use the sound card to decode and display AIS data on your
laptop see this web page:

http://www.coaa.co.uk/shipplotter.htm

Here are a few more interesting links:

http://www.xmradio.com/weather/
http://www.xmradio.com/weather/av_subscription_pkg.pdf
http://www.garmin.com/products/gpsmap376c/

http://www.nasamarine.com/press/pdfs/sx35.PDF
http://www.nasamarine.com/press/pdfs/sx35pract.PDF
http://www.nasamarine.com/press/press.html

"Larry" wrote...
Holger wrote

Self-transmitting is normally used when environmental data is also
transmitted.


Oh, wouldn't THAT be nice if all the NOAA offshore bouys and fixed
stations
transmitted their data on AIS.....so you could see live how the wind and
waves are doing up ahead.

Other than realtime data, I see no reason to risk a radio system on a
bouy.


I believe that you can get NOAA weather bouy data via XM satellite radio
today:

Here is more info on signing up for XM satellite weather.
http://www.xmradio.com/weather/
http://www.xmradio.com/weather/av_subscription_pkg.pdf

Go here http://www.xmradio.com/weather/marine.html and click on "Bouy
data".
"Buoy observations are taken from marine buoys and coastal observation
stations to determine wind speed, direction and gusts; air and sea surface
temperature; dewpoint; sea level pressure; wave height, period and
direction; visibility; pressure tendency and tide change. Data Broadcast
Frequency: 12 minutes"

Here some examples of two Garmin GPS units that receive and display XM
satellite weather data:

http://www.garmin.com/products/gpsmap376c/
http://www.garmin.com/products/sp2730/

www.tvnav.com has the Garmin 376c for $805