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Nobeltec InSight Radar (IR2)
Operations Manual
Creating a Compass Deviation Table
Due to magnetic interferences and other considerations, magnetic compasses
can provide inaccurate information. To complicate this matter, the level of heading
innacuracy can change at each compass heading. To resolve this, inside the
Nobeltec software is a table that allows you to enter correction values at each 5°
increment.
Tip: Using a Combination GPS/Heading sensor that determines
heading based on dual GPS antennas (instead of magnetic)
significantly improves the accuracy of incoming heading data and
simplifies the radar alignment process.
Once you have resolved the radar heading line and compass master rotations, you
now need to test the radar alignment at various headings to discover the onboard
deviations. The easiest way to do this is to be on the water in a clear open area and
drive at each heading for a short while correcting the deviation as you go.
An example of a way to do this follows:
1) Once on the water with the Nobeltec software running with radar and the head-
ing sensor, open the Compass Deviation Adjustment tool (click on the Deviation
entry button in the Compass Heading Corrections window - shown above).
2) Steer to magnetic North.
3) With a chart window open with radar overlay turned on, observe how the radar
lines up with the chart. If the radar does not line up correctly, use the screen
above to rotate the radar image to the chart. Once lined up, hit the Add button to
add this value to the deviation table.
4) Now, change the vessel heading to another heading and repeat the process until
you feel confident that the radar image lines up with the chart at each heading.
Setting up IR2
