Onwa Marine Electronics KAP-833 - Manual (Page 18)

This setting is used to determine the amount of rudder the vessel requires for
steering (actually, the amount of rudder angle applied for a given angle off course).
The centre position is usually suitable for most vessels, but should the vessel's
steering be sensitive or slow, adjustment maybe required.
In general, an agile vessel with a relatively large rudder or very small keel will
require a small rudder setting. A large, slow vessel may require a high value for
the rudder ratio.
This may also be adjusted according to speed - low speeds may require more
rudder angle for steering than high speeds.
A value of 1 signifies the minimum amount of applied rudder (for sensitive
steering, large rudders or low gearing ratio.)
A value of 10 signifies the maximum amount of applied rudder (for vessels
with slow steering, small rudders or high gear ratio.)
When the rudder setting is too low, turns will take an excessive amount of time
and the vessel may
wander .
When the rudder setting is too high, turn will be rapid and the vessel will
oversteer.
Rudder(Rudder Ratio)Control 3 4
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