T&T: AIS

[Peter Bennett]

Wednesday, September 12, 2007, 11:07:39 AM, David wrote:

DHS> I am certainly aware of AIS, but figured we would probably never get one,
DHS> so I have not paid a great deal of attention to the matter. However, we
DHS> do plan to do the loop in the future and recent postings here and
DHS> elsewhere have made clear how helpful AIS is on the inland rivers.
DHS> Therefore, a couple of questions for the infinite wisdom of the list:
DHS> 1. I presume that an AIS system requires at least one or possibly two
DHS> additional VHF antennas. How many to be exact?

One antenna - although there are switch/splitter devices available
that allow the AIS receiver to share an antenna with a Marine VHF -
with one of these, you don't need an extra antenna.

DHS> 2. I understand that most recreational boats will use a passive Class B
DHS> receive-only type of AIS. Is an active mode desirable (or permissible)
DHS> and if so, how much does it cost versus receive only mode?

I think the "Class B" term refers to a transponder device that both
transmits and receives.  Don't think any are approved in the US or
Canada yet.

Most pleasure boaters that have AIS will have a receive-only system
such as the SR-161 from http://www.milltechmarine.com/ - about US$189.

DHS> 3. Does the AIS receiver interface with a PC-based chartplotting system
DHS> or can it work directly with a dedicated chartplotter. If so, which
DHS> types? Is the interface by USB or 232 serial cables?

The SR-161, which I have, outputs RS-232 serial data at 38,400 baud.

To make use of this information, you will need a chartplotting program
or dedicated chart plotter that is aware of AIS, and can display the
information in a useful manner. You will have to consult the
documentation on your favourite chartplotter/plotting program to see
if it supports AIS.

-- 
Peter Bennett, VE7CEI    Vancouver, B.C., Canada
Ennos 31 "Honeycomb"
GPS and NMEA info: http://vancouver-webpages.com/peter 
Vancouver Power Squadron: http://vancouver.powersquadron.ca