NASA Marine CLIPPER, Руководство пользователя

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HEADING ADJUSTMENT
It may be necessary to make a minor adjustment to the sensor alignment to ensure that
the Compass correctly measures the vessel’s heading. If an adjustment is found to be
needed, accurately point the vessel to a know heading. Either MAG. or TRUE is
displayed to remind the user which physical alignment of the vessel is to be used.
If the display does not show the known heading, the sensor unit must be rotated
slightly to bring the display into alignment. Slacken the sensor unit’s mounting screws
sufficiently to allow the unit to be turned, and rotate it until the display shows the
know heading. Then re-tighten the sensor unit’s mounting screws to lock the
compass calibration at that position.
REPEATER FACILITY
The Clipper compass display unit takes in un-compensated magnetic readings from
the sensor unit, and transmits the compensated (if the compass has been swung)
heading and the magnetic variation stored in the unit in a standard NMEA 0183
$HCHDG... string.
5. Press INC to advance the display by 45°, and then continue the sequence at instruction 3
until 315° has been logged.
6. When all the errors have been logged, Press INC and DEC together to return to
Engineering.
7. Press ILLUM to return the unit to normal operation.
As a final test, the vessel can be swung to confirm that the compass is operating
satisfactorily with all errors correctly compensated.
Note that it is not necessary to do all the settings as described above at the same session,
and the fixed headings (45°, 90°, 135°, etc.) can, if desired, be checked at different times to
improve the compass’s accuracy. Likewise, if the error at a particular angle is known to be
negligible, there is no need to align the vessel and log the compensation at that position.
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