Nautical Measured Mile Markers - Raymarine i70 Operation Instructions Manual

1 SOG speed reading
2 Current speed reading
If SOG data is not available then the SOG value will display dashes.
9. Accelerate your vessel to a steady, typical cruising speed.
10. Use the Up and Down buttons to adjust the current speed reading so that it matches the SOG
reading or matches your estimated speed.
11. Select Done when both values are the same.
The calibration complete page is displayed.
12. Select OK.
If you experience significant deviation between SOG and log speed readings at different vessel
speeds then a Speed Run Calibration should be performed. Refer to the
Calibration using SOG section for details.

Nautical measured mile markers

When neither SOG data or any other reliable means of estimating Speed Through the Water (STW)
is available, Nautical measured mile markers can be used to help calibrate Log speed. Nautical
measured mile markers are identified by two pairs of posts or towers. The distance between each
pair of markers is 1 nautical mile.
Each marker in a pair is separated by distance and elevation from its partner. The front marker is
closer to the water and shorter than the marker behind it.
Transducer calibration
Performing a Speed Run
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