I own a Raymarine ST3000 Autohelm and all of the sudden one day it reads the wrong compass heading. I tried to recalibrate and was able to get it dead on but when I engage it takes the helm about 30 degrees to starboard and can't seem to find the heading wanted it just keeps searching and searching. Has the control head gone bad and do I need to send it to you for repair? If so how much will it cost? Or is there something I can do to maybe get it back to the default settings? It was working fine for the past 6 or 7 years then all the sudden its doing this. What's Up?

SOURCE: My plotter seems not to output NMEA to my DSC radio and auto helm

Your plotter can talk to you Radio and your pilot. It sounds like one of two things.You must go into the system setup menu and turn on the nmea sentances. You will need to turn on RMB, RMC, GGl at least. You can turn on all the sentances if you like it does not matter. If this does not fix, check color of wiring is correct. Remember you have to go from NMEA + out (on plotter) to NMEA + IN on Radio.Then you need NMEA - out(on Plotter) to NMEA - IN on Radio.
You can look at the sentances wirth a multi meter coming out of your plotter. You put meter in DCV and connect across the NMEA out lines. You will see the meter move every second or so as it send a sentance.

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SOURCE: Compass reading on GPS 60cSx about 30 degrees too high

Calibrate the compass (Main menu --> Setup --> Calibration --> Compass), follow the instructions on the screen.
Also, see page 50 of the manual.
Calibration must be done outside - stay clear of any large metallic object (e.g. car).

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