Simrad AP28 Operator's Manual page 62

Units of measure
62 | Main menu
Parameter
Boat speed
Wind speed
Distance
Depth
Heading
Temperature
The display unit for heading data is not solely determined
by the user. If true heading is wanted but the selected
compass is a magnetic compass, then the magnetic
variation must be available from a position source. The
same applies if the user wants to read magnetic heading
but receives true heading from the compass.
If magnetic variation is required but not available, the
compass decides which unit to display.
Options Default
− kn
− km/h
− mph
− kn
− m/s
− mph
− nm
− km
− mi
− m
− ft
− °M
− °T
− °C
− °F
kn
kn
nm
ft
°M
°F