Compass

[Fin]

For some reason my Raymarine compass has just stuck at 135deg. Tried all the connections, it was working and I don't think I've changed anything! Compass feeds into the back of a ST4000+ auto helm with some ST50 displays on the same system, its a bit heath robinson but has been working.

Fin

 

[hightech]

135deg sounds like a compass not connected value.

Assuming the compass is not a Seatalk output one (3 wires) and is just a fluxgate compass (5 wires) you can check the coils with a ohmmeter, there are basically two coils, one plain and one with a centre tap, hence 5 wires. The resistances I would expect to see is 6-12 ohms across the outside ends of both main coils, then half the value seen between either end and the centre tap (3-6 ohms) the two coils are not connected to each other. If you compass is a Seatalk model, then the internal compass will be 5 wires and can be tested again with a meter, but will need to be disconneted from the circuit board.

If this makes no sense then I could send you a sketch.

Hightech