Yup, that's normal. The idea is that the autopilot should never make a course
change without a human checking to see that there isn't, for instance, a kid in
a rowboat on that bearing. This is a function of the autopilot design, not the
GPS or the connection. I encountered this in the design of my NMEA data
repeater program. Since I can't hear the beep of the autohelm from the cabin, I
have the program turn the waypoint display red when the waypoint arrival message
is received. Of course, this only helps if you are below, watching the screen,
which you shouldn't be. There really should be provision for an external alarm
on the autopilot.

Glen Wilson


On 17 Aug 2003 04:30:17 -0700, (ryeg) tempted fate with:

I have a Simrad ST20 AutoHelm hooked to a Garmin ETrex GPS and it
works quite well, but it requires me to manually reset the autotiller
at each waypoint change. When a waypoint is reached the tiller
'disconnects' from the the GPS and, if I don't reconnect by pressing
the tiller Navigation button, it just continues on the last course --
i.e. it doesn't move on to the next waypoint in the list. The
TillerPilot does let me know that it is going off line by beeping, but
between outboard noise and my poor hearing I sometimes don't hear it.

I wonder if this is normal behavior or if I am missing something.
Neither Garmin nor Simrad give much information about hookup or
operations in the NMEA mode. Any pointers appreciated....

Otherwise the setup is great fun and makes some of the long runs under
the "iron wind" quite livable.

Rye WWP19 -- Potomac River/Washington DC area (WSM)

Glen "Wiley" Wilson usenet1 at worldwidewiley dot com