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heading adjustment ... when does it stop?
#11
What type of adjustments? How much is the error each time? Does locking the calibration help?

Does your moitessier hat have the metal shield over the radio? It is magnetic, test with magnet, and far too close to the compass sensors. I may have a very early moitessier hat.

Pypilot continuously computes the compass to GPS offset for GPS mode. It steers compass course plus this offset since GPS is too slow to use directly. This offset accounts for leeway, currents, and compass errors all together.
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#12
(2019-08-13, 04:30 PM)seandepagnier Wrote: What type of adjustments?   How much is the error each time?  Does locking the calibration help?

Does your moitessier hat have the metal shield over the radio?  It is magnetic, test with magnet, and far too close to the compass sensors. I may have a very early moitessier hat.

Pypilot continuously computes the compass to GPS offset for GPS mode.  It steers compass course plus this offset since GPS is too slow to use directly.  This offset accounts for leeway, currents, and compass errors all together.

Hi Sean

So here is a screen shot of an example https://drive.google.com/file/d/1it0v_Uk...EAPc4/view
This happens on compass mode or gps mode but definitely happens anytime I switch between the two, it also happens when I change heading say like 180 degs.

Strangely enough the adjustment is usually about -30 degs or +30 or close to zero something like 3 or -3 but from -30 to +3 or vis-versa depending on the day, 
I have to lock calibration if I do not I am unable to maintain a heading
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#13
If you must lock calibration then do so, but I would carefully look at the calibration plot while it's unlocked to understand what is going on.

It's most likely there is magnetic interference of some kind.
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#14
(2019-08-17, 05:04 PM)seandepagnier Wrote: If you must lock calibration then do so, but I would carefully look at the calibration plot while it's unlocked to understand what is going on.

It's most likely there is magnetic interference of some kind.

Ok, so how far from  speakers should it be? currently its mounted on the opposite side of the helm as close to the middle of the boat as possible I would estimate it is 30 - 36" away from the speaker mounted on the starboard gunwal and it would be approximately 60" from the speaker mounted on the port gunwal.... Do you think that is too close?
Its really the only spot on the boat that doesn't get splashed in rough conditions. 
Another thing at the helm is my gps/depth sounder, they are roughly 30" away... not sure if they produce magnetic interference or not though..?
Also, what am I looking for in the calibration plot?
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#15
        This is what it looks like atm, its parked on the trailer though....
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#16
(2019-08-21, 01:16 AM)rastam4n Wrote: This is what it looks like atm, its parked on the trailer though....

The calibration looks like it worked for 2d fix (boat in flat water)   If the compass readings are sensible (go from 0-360) it is good enough for the autopilot to hold course.
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