Chapter 6: Calibration
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Log calibration
The ST30 Bidata should not be used for navigational purposes until the
transducer paddlewheel has been calibrated to suit the characteristics of
the vessel.
This is a simple operation and is carried out as follows:
1.
Choose two charted points that are approximately 1nm apart.
Approximately 1Nm
Point 1
Point 2
D699
2.
Choosing a time when the tidal flow is at a minimum, go from point 1
to point 2 and record the ST30 Bidata trip distance.
3.
Go from point 2 to point 1 and record the trip distance.
4.
Add the two distances together and divide by two to obtain an
average distance.
5.
Measure the distance between the two points on a chart.
6.
The correction factor (CF) can now be calculated.
CF =
Charted Distance
Average Distance
