Robertson Hyd. Arm/Simrad Control Unit

[tardog]

I have an older boat that came with a non-operating Robertson autopilot. It utilizes a hydraulic arm, which seems to be in fine condition, but the control unit is dead in the water. Looking at a new Simrad unit, the hydraulic arm looks identical to the one I've already got. So I'm wondering what the likeliehood is a new Simrad control unit will coordinate with the old arm. Sure would save some $...anyone have any knowledge of the compatibility of these two?

[slacker]

One of the inportant things to remember is that Robertson/Simrad dosent make pumps or rams. If you look at a Comnav, Robertson, Simrad, Autohelm, RayMarine ect pump you will notice that they are all the same. There are typically two sizes that are matched to the ram size and vessel weight. Robertson/Simrad calls theirs the RPU 80 and RPU 160. Most rams are manufactured by Hytonics.

To answer your question, they just dont care. The pumps have a 3 wire control hookup from the junction box that sends a signal to the motor to spin the pump clockwise or counterclockwise.

If you have more questions call Simrad. They use to be Robertson and I have found them very helpfull.

We have a 25 year old Robertson system that I have kept functioning by purchasing parts off ebay. Its amazing how many of them their are out there. Ours now uses an AP200 control head, a junction box origonaly from a AP25 system.

I have purchased two complete eletronics packages (for spares) piece by piece, never paying more than $ 30 for each.

Good Luck

[CARL]

My Robertson ap packed up last year i replaced with a simrad control and upgraded compass the same time ,ram is origonal, result is a far better more responsive pilot .i would certainly recomend upgrading the heading compass.