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  Topic Review (Newest First)
03-14-2008 07:44 AM
soul searcher leave the ferrets at the dock.

I fight my pilot on the sail boat constantly. I'm always trying different setting and cant seem to remember that the the pilot can only react to conditions it can't anticipate them I don't care what the marketing says.
So in variable speed and shifting winds that pilot will get a work out especially if your boat isn't balanced.
for example; If you have some weather helm your boat will want to round up and double that if it's gusty. so the pilot reacts to every puff. What may help you is to change the buffer setting to make the pilot react a little slower. this is particularly good going down wind but up wind it wont react fast enough so you have to tune to some sort of middle ground.
Pilots will not steer as good as you can because they cant anticipate.
but they have a longer attention span than most people.
the number one killer for me though is helm balance if that helm isn't balanced then that pilot will have to work it's ass off and it will start makeing that snake wake.
I think we expect to much from them.
03-13-2008 10:18 PM
okapi3 Thanks for all the input. Now, to answer your questions: the autopilot uses a wheel pilot and as I recall from last season (the boat is on the hard right now) there was no difference in the feel of the wheel between sailing vs. motoring. I believe the linkage is mechanical and not hydraulic. The oscillation starts out small in amplitude and then gets bigger and bigger until I shut it off so the Coast Guard doesn't pull me over for drunk sailing. The period of oscillation seems pretty regular. As far as the stereo goes, it went in the trash as soon as I got the boat--if it were any older it would have had an 8-track. Need to replace that sometime. Would the same thing happen with the VHF--hearing the motor on the radio? I don't know if it is was factory install or not. And,come to think of it, I don't think the problem occurred with the motor on but not in gear, but I'll test that when I launch her, very appropriately, on April Fool's Day. And lastly, about those ferrets. I'll give 'em a try, but I'm not too crazy about having a bunch o' nasty,sharp-toothed varmints on board.
03-13-2008 10:39 AM
thekeip A very common 'oversight' is to ignore the absolute requirement to do the deviation calibration, per the Raymarine manual. Your symptoms sound like textbook indications of same.
Howard Keiper
Sea Quest
03-13-2008 08:15 AM
Jotun I'm pretty sure it's the ST 4000+, wheel steering, seperate flux gate compass. It was installed by the PO of my boat and has never worked properly, holding course for a minute or so before wandering off. I have very little experience with autopilots, so any help or suggestion is welcome.
03-12-2008 05:39 PM
sailingdog Jotun—

It would help if you gave some more information, like what model ST... They made five or six STx000 models at least. Tiller or wheel or under deck steering? Integrated or separate flux gate compass? What model control head? etc.
03-12-2008 04:14 PM
Jotun I have a similar problem, except my ST does it with sail or motor. It seems to hold a course for a minute or two, and then it suddenly goes way off course to port or starboard. Is there anything I can do or is this a Raymarine fix?
03-12-2008 10:34 AM
chucklesR oops, my bust - fingers going faster than brain. It's actually 'anti-magnetic' in that what it's doing is busting up the electromagnetic interference.

Longer explanations available. Don't believe the hype about them being used to prevent interference from getting out of a device, they block interference regardless of direction.
03-12-2008 10:19 AM
sailingdog Ferrites aren't generally magnets Chuckles.. they're just lumps of iron ferrite...hence the name...
03-12-2008 09:44 AM
chucklesR How's the reception on your onboard stero with the engine running? Sounds to me like your alternator is throwing electrical interference down the circuits.
If you hear the motor through your stero that's a pretty good verfiication of that.
Ferrites (small magnets) are one solution - and recommended for delicate electronics. Easy to retrofit as well - just go to radio shack, get a couple and slip them over the DC lines in the back of the power panel. Actual results may vary depending on how big the problem is.

The real solution is to root out the cause (again, likely the alternator) and fix it there with proper grounding and isolation.
03-12-2008 09:39 AM
dsbentley I also had some issues with my ST 7000 autopilot on a sail back to St Croix from St John. We were under sail only with 18 knot winds from the East heading 190. I had the full Genoa out as well as the main. The rudder indicator showed holding a few degrees to the starboard side and the swell was out of the NE. This seemed to cuase the boat want to turn back to Port after a big swell would pass and then the auto pilot would not keep up. I hand steered the last two hours and found myself constantly holding right rudder preasure then steering back to port every few seconds. I have hydrolic steering so I think the Auto pilot was just not able to keep up with the corrections needed. I am also wondering if I could have trimmed the sails better to help this problem.
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