Rudder Damping; Variation - Raymarine ST600R Owner's Handbook Manual

Chapter 5: Customising the System

Rudder Damping

You only need to set this option if your system includes a rudder
reference unit, and the drive "hunts" when trying to position the
rudder. Test for this when your vessel is moored dockside, by
pressing AUTO and then +10. If the helm overshoots and has to drive
back or starts to hunt back and forth, you need to increase the
damping level.
In auto mode (A), the autopilot applies damping compensation
automatically – not available if using a Type 100/300 Course
Computer.
Alternatively, you can set a value in the range 1 to 9. Adjust the
damping one level at a time, and always use the lowest acceptable
value.
Range:
Default:

Variation

If required, set this value to the level of magnetic variation present at
your vessel's current position. +ve variation = East, -ve variation =
West. The variation setting is sent to other instruments on the
SeaTalk system, and can be updated by other SeaTalk instruments.
Range:
Default:
1 to 9
1
-30° to +30°
Off
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