Heading Sensor vs. Solid State Compass?

[carlylelk]

I'm confused with the terminology.

My Chartplotter Manual says it needs a Heading Sensor to overlay the Radar on the chart.

I'm thinking of using the Airmar 220WX for wind at the top of the mast, especially since it incorporates a GPS and a "three axis solid state compass with dynamic stabilization".

Is "Heading Sensor" just another term for "solid state compass"?

One other thing: Is a compass at the top of the mast subject to error or wide swings due to mast movement in a sea? What about the GPS...same question?

Thanks,
Duane

[DotDun]

If you have an autopilot, check to see if you can use it's compass to feed the chartplotter. Typically, radar overlay requires a 10hz update rate, but I've seen radar overlay work on 1hz update rate.

[Suijin]

The airmar compass should work assuming it’s outputting NMEA2000 data and is on the backbone with the chart plotter. The readings are damped to compensate for fluctuations from mast movement. If you have an autopilot it almost certainly is using an electronic compass, ideally located near the boat’s roll and yaw axis.