GARMIN MSC10 Marine Satellite Compass / NMEA2000

Unfortunately, the satellite compass (optimally installed, without radar interference and without impaired visibility) in the delivery state (i.e. without automatic switching to magnetic compass, i.e. purely satellite-based) varies by 5 degrees within 15 minutes (boat tied to the harbor wall). A standard magnetic compass can do that too.

In addition, the built-in magnetic compass can only be activated effectively with Garmin displays.
I was unable to activate it for third-party display plotter systems with driving exercises (according to the instructions) on the open sea with precisely running IPS drives and no wind with only 20cm waves, even on the 4th attempt.

Unfortunately, the Garmin satellite compass keeps losing its heading when the boat is not moving or hardly moving (e.g. when anchoring).
According to the instructions, this should only be the case in exceptional cases under bridges and the like (but there are no bridges on the open sea). My Raymarine plotter immediately sounds an alarm when it loses its heading (even when the engine is turned off and there is no autopilot). This means that you are woken up countless times when you spend the night at anchor. This is probably what the integrated automatic switch to magnetic compass is designed for. But despite calibration (according to the instructions), this does not work or is too slow. So the alarm still goes off. The only solution is to set the plotter to automatic source selection for the heading. But then the plotter always uses my Volvo magnetic compass and not the MSC-10.

And another thing: with a Volvo IPS system with a Volvo compass and Volvo autopilot (both are actually from Garmin), the autopilot does not allow the heading source to be set to the Garmin MSC-10 compass. The Volvo compass is used. And although my Volvo autopilot display is actually from Garmin, you cannot use it to calibrate the MSC 10 (it is displayed, but there is no way to access it). So you need a 500 EUR display from Garmin (e.g. GMI 20) just for the calibration.

The bottom line is a waste of time and money. The MSC-10 is stylish but nothing else. A decent satellite compass from Furuno costs a bit more. SVB only has the smallest Furuno - unfortunately I don't know if it's any good.