Geoff Schultz wrote:

John Navas wrote in
:

On Thu, 11 Jun 2009 05:34:49 -0500, Geoff Schultz
wrote in
:

Has anyone seen any used AIS class A transponders for sale? I do
enough off-shore sailing to want a class A instead of a class B.

Class A is probably going to cost you at least $3,000
http://store.milltechmarine.com/acrglaistr.html,
versus less than half of that for Class B:
http://www.wmjmarine.com/ait250.html
http://www.consumersmarine.com/modpe...gi?r=view&i=98
0030 Why do you think it's worth the additional cost?

Up until today I was one of those under the false impression that AIS
displays would be able to filter out class B information. According to
something that I just read on Panbo.com, this impression is common, but
false. The last thing that I wanted to do was to be doing an off-shore
passage and have my information filtered by an approaching ship.

Here's a link to the article:

http://www.panbo.com/archives/2009/04/ais_solas-
style_class_b_is_not_ignorable.html#more

I am also a bit concerned about ships not upgrading their software to
include class B messages. I know that until I recently upgraded my
RayMarine software, that it didn't understand class B messages.

However, after reading the article on Panbo, I feel much better about class
B and will probably get a class B.

-- Geoff
www.GeoffSchultz.org

I have a class B unit (ACR) and the big guys see me. Of course I see
them from farther away, but that is an antenna height issue and would
be true of class A also.

Michael Porter
Michael Porter Marine Design
mporter at mp-marine dot com
www.mp-marine.com