O.K easy question?
How do I make my ST4000 and my boat compass read in the same direction?
I know, and have read how to swing them both for deviation. But the ST4000 control head when i hit auto keeps the wheel on target but it reads off? Is there a way to set it close? Thanks.
I'm guessing that by "boat compass" you mean a standard magnetic compass.
The fluxgate compass is also a magnetic compass - it has some electronic circuits that measure the magnetic filed that surrounds it.
All magnetic types of compasses is designed to "read" the magnetic field of the earth to give a direction relative to the magnetic north.
The problem is that on a boat we have several other magnetic sources that disturbs the magnetic field the compass "see".
Depending on the placement of the sensor the disturbances will change.
I don't know where your fluxgate sensor is located but it's probably not in the same place as your "boat compass", so these two compasses "experience" different magnetic fields (noise/disturbance).
Which compass that is correct is impossible to know without doing proper compass deviation checks (for every 10th degree around the circle).
I don't think you can override the courses shown by the control head, but I think you can do a manual correction on the fluxgate instead of "swinging" it.
You will never get these two compasses to show exact same course on all headings.