NASA Marine CLIPPER SPEED AND DISTANCE LOG, Manual

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12
ILLUM
F
TOTAL
Set
SPEED TRIP ILLUM
A
TOTAL
Set
SPEED TRIP
Figure 9 -Switching between Fast and Averaged
speed display modes
CHANGING THE CALIBRATION
The calibration factor determines the number of revolutions of the
paddle wheel required to represents 0.1 miles or nautical miles. The
calibration of the unit is set up in the factory and the value is stored
in the unit’s memory. However, the type of hull and the position of
the paddle may affect the performance and cause the speed (and
distance) to over-read or under-read.
Press the TRIP button to see the calibration factor, which is pre-set
to 100 in the factory, to give correct readings in free flow conditions.
The same factor is used for speed and distance measurements. The
facror can be increased to 150% or decreased to 70% in 1% steps.