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Larry

wrote in news:1176244717.431800.16850
@n76g2000hsh.googlegroups.com:

I am well aware of the benefits of having the GPS talk to the
Autopilot but any reasons for having the rest of the instruments
communicate with each other, escape me.

Until you add navigation computer software.....

The Cap'n, for instance, uses the wind, speed log, depth, and other data
in making its "informed" decision on what to tell the autopilot to
do....not just steer a course. It uses drift caused by wind and current,
extrapolated by the GPS as well as the wind to make course decisions,
putting in the appropriate crab angle to get the desired course over
ground, constantly adjusting the course it wants the autopilot to steer
as conditions change. At night, you can switch it into wind mode and
have it steer the boat, in the dark, to the relative wind, instead, IF it
has WIND data to use, of course....

Once filled with these sailing instrument outputs, it's like having a
ghost at the helm...a very well-founded helmsman ghost, indeed. Now, the
ghost is watching and plotting AIS aboard the ghost ship "Lionheart" with
the latest version. MO DATA!

In an effort to force you to buy THEIR brands, manufacturers are
proprietarizing (is that a word??) their "systems" to prevent, or at
least retard, your choices.

This is why we decided to add more B&G "Network" instruments to the ones
already aboard Lionheart (Amel Sharki 41 ketch) when my friend Geoffrey
bought her. B&G Network instruments, including B&G Pilot, which, itself
quite independently if you like, can read all the wind/speed/depth/etc.
sailing instrument data in its NMEA-0183 "loop" B&G ingeniously created
to get around the stupid ONE talker limitation of NMEA 0183, while
retaining all the data for external use. These instruments are no longer
produced, but they are available from many sources. A standardized
jumper cable goes from instrument to instrument putting all of them in a
loop, even the control head for the Network Pilot autopilot. The
standard NMEA-0183, standard speed, data jumps from instrument to
instrument around the complete loop, with each instrument retransmitting
what it has received, while adding and updating its own particular NMEA
statements and passing it all on to the next instrument. This works just
great! Independently from any external computer, you can simply switch
Network Pilot to WIND and it ignores data coming in the NMEA IN port from
the external NMEA network outside the B&G loop...steering the boat quite
happily from the B&G WIND instrument's speed/azimuth output inside the
loop. This gives us redundant steering from many sources, in case of
equipment failure or computer crash, instantly, with no changes other
than pushing a button on the Pilot. Works great and the "learning" the
Pilot's computer does to smooth out turns, etc, is uncanny. B&G's NEW
instruments all have a proprietary data network that's not friendly to
outsiders....on the NMEA network. I'm glad I'm not fighting that extra
conversion box they sell to translate it. With B&G "Network", you just
opened any wire in the loop and tapped the data out of the inside of it
and fed it to your multiplexer input (only 1 for all the B&G instruments
in the cluster). No translation was necessary...less boxes.

The coordinated turns in any REASONABLE wind/current/speed situation is
so smooth....no overshoot or undershoot....Ghosts don't oversteer..(c;

Larry
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