1) check repeater with a master compass to ensure that repeater is functioning properly if Power fails repeater may have to be reset.
2) check the compass error by azimuth
3) speed and latitude characters should be reset as necessary
4) inspect the compass to guard against any abnormal condition of operation.
a) Check the alarm buzzer.
b) Clean and oil any part as indicated in the manufacturer’s manual.
c)General cleanliness should be checked repair and maintenance should only be carried out by a professional.