T&T: AIS

[Bob Peterson]

Peter, not only will you "need a chartplotting program or dedicated chart
plotter that is aware of AIS, and can display the information in a useful
manner", you will also need an older PC that still has a serial port, an
increasingly rare feature these days.  One wonders how many Serial-to-USB
adapters we'll need to use on our Nav PC's to connect everything.

Bob Peterson
"Lopaka Nane"
47' Lien Hwa CPMY
San Francisco

-----Original Message-----
From: trawlers-and-trawlering-bounces at lists.samurai.com
[mailto:trawlers-and-trawlering-bounces at lists.samurai.com] On Behalf Of
Peter Bennett
Sent: Wednesday, September 12, 2007 5:36 PM
To: David H Sorenson; trawlers-and-trawlering at lists.samurai.com
Subject: Re: T&T: AIS

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

DHS> I am certainly aware of AIS, but figured we would probably never 
DHS> get one, so I have not paid a great deal of attention to the 
DHS> matter. However, we do plan to do the loop in the future and recent 
DHS> postings here and 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 
DHS> two 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 
DHS> Class B receive-only type of AIS. Is an active mode desirable (or 
DHS> permissible) 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 
DHS> system or can it work directly with a dedicated chartplotter. If 
DHS> so, which 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"