Heading indicator, electronic compass, same thing. Basically it figures out what way the boat is facing and can interface with other instruments to provide MARPA data (where my radar tracks targets) and radar overlay. And, most importantly, sends heading data to the autopilot.
My standalone GPS (GS25) does provide heading data as well, but almost incidentally. It’s not rated for autopilot use and so I needed a dedicated heading sensor. Apparent the H2183 is the best on the market (without getting into satellite compass systems, since to afford those I’d have to sell both legs and a kidney)
Installing was very simple.
First I installed the bracket, using a level to make sure it was aligned correctly
Then attached studs to the bottom of the sensor that would hold it in place
And then drilled the hole for the wire and connected it. It’s attached to a bulkhead right by the compression post.
Then I connected it to the NMEA2000 network, and it was detected.
Still have to calibrate the thing on the water, but that’s the first part of the autopilot system installed!