TMQ Bosun-AP9, Operation And Installation Manual

Page: 39 / 63

TMQ Bosun - AP9 Rev1 (935) Page 39 16/06/2003
Compass Calibration
The compass supplied with your Bosun autopilot has been calibrated
during manufacture. This calibration will be satisfactory for almost all
installations. If you have a steel vessel, or some other factor, which causes
the compass to perform poorly, the calibration procedure will adjust
compass characteristics to compensate. The calibration should only be
done if the compass is
known to be inaccurate.
If the Bosun compass displays a
constant offset (eg the autopilot compass
reads 3 degrees high on all bearings ), simply rotate the Bosun compass
case to align bearings with the ships compass, it is not necessary to re-
calibrate the compass as described below.
If the Bosun compass has inconsistent variation on different headings, the
following calibration procedure can be carried out. This procedure should
only be done in calm waters with adequate sea room.
1. Select STANDBY .
2. Enter "901" by using keypad, then hold down GOTO , press
STANDBY , then release both buttons together. ‘ CAL ’ and the
current heading will be alternately displayed.
3. Turn vessel slowly through two complete circles in same direction.
4. When the circles are complete, enter "902" by using the keypad,
then hold down GOTO , press STANDBY , then release both
buttons together.