There is a hydraulic driven ram drive for the Simrad Dawg and it works fine and is more reliable than the screwtype linear drives in my opinion. I have owned both types and presently have the Simrad on my cable driven quadrant. I am well pleased with the performance.
Oz...the nice thing about the under deck quadrant attachment is that if your steering cables fail which is not an uncommon occurence...you can still steer the boat with the auto pilot. Have no fear...underdeck is the way to go if you are cruising in a larger boat and have the room and access for it.
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