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Old 10-06-2013
arf145 arf145 is offline
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Question Seatalk Cross Interference

I've got an interference problem among my new-to-me but 12-yr-old Raymarine instruments: ST60 wind, ST60 Tridata, ST4000+ autopilot. These are all powered by Seatalk connectors in this order: power comes into the ST4000+, then Seatalk to the Tridata, then Seatalk from the Tridata to the Wind.

The problem is between the autopilot and the wind instrument. Whenever the autopilot is driving the wheel, the wind direction moves as if in a trance and the windspeed becomes random. I've been out in 99 kt winds! On the other hand I've seen some evidence that the autopilot is also disturbed: it will keep a course but allow 10 degree swings while doing it sometimes.

I've isolated the drive cable for the drive part of the wheel pilot so it isn't running alongside any of the other cables, but this did nothing. I also see that someone put a ferrite core on the drive cable as it came out of the ST4000 control. This is Seatalk 1, so no termination is required on the last instrument, as I understand it.

Anyone have any ideas?
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2000 Beneteau 331
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