"Larry" wrote in message
...
Time for a yearly update. I had a Bombardier Utopia - an 18' jet-powered
runabout that I added an autopilot to, but while it did work at higher
speeds, it failed miserably for trolling and fishing in general. Last
year I sold it and bought a center console Cobia, a 21' with a 150 hp
Yamaha outboard. I added a 15 hp (smallest I could get without ordering)
Suzuki outboard to use as a trolling motor. It is tied, mechanically, to
the larger Yamaha and sips fuel from the same large tank. It works pretty
well, and steers a straight course with no hands on the wheel.

Still, I'd like to add an autopilot IF (and only if) it can operate at
trolling speeds (about 1 knot or 1.5 mph). ComNav makes a few units which
look like they'd work, but I'd like to hear that from someone other than
the manufacturer or salesman, preferably someone who owns one. The boat
is equipped with a Garmin 540 combination fishfinder/GPS chartplotter
which issues NMEA sentences.
--

You need an autopilot where you can alter the amount of response to a given
course deviation.
At trolling speeds you need much more rudder angle to correct a deviation
than you would at higher speed.
However, if you are trolling rather than maintaining course to a destination
you ought to be able to accept a greater amount of yawing about the set
course anyway.