Internal Heading Sensor Calibration on a Cortex Hub

The Cortex Hub includes an internal heading sensor for use when an external heading device is turned off or unavailable (if the autopilot is turned off). The internal heading is used in AIS position reports, anchor watch bow position corrections, and wind direction calculations. 

The sensor must be calibrated before use to use the internal heading. Much of the information calibrates automatically once the vessel is underway, where the Hub will learn the correction offset, its installation orientation, and any magnetic effects from other objects or instruments near it.

A configuration menu is provided under Sensors>Heading to speed this process up. While underway, do a complete 360-degree turn; when enough data is collected during the 360-degree turn, a message "Calibrating... hold your course for five seconds. If an external heading sensor is not connected, assure that the SOG is greater than 3 knots." During this stage, the Hub calculates an offset correction to the boat's bow. Either an external heading or the Hub's COG needs to be stable before being used as an offset correction source. 

For instance, repeat this process if the Hub is moved or repositioned in the boat. A Reset will clear out all the bias and orientation data, requiring you to start the process from the beginning. A reset is recommended if you have moved the Hub, changed its installation orientation, or something else in the Hub's environment has changed. Recalibrate will only re-compute the bow offset correction using either an external heading or the Hub's COG, but keeps all the magnetic model data.