Is the pod on the right wing of the PC-12 and Cessna 208 a gyrocompass?
Its not the gyrocompass. Its where the weather radar unit is mounted since the prop prevents it from being mounted in the nose like on many larger aircraft. You can find a nice instructional video on how to use it here. The magnetometer used on many aircraft to provide magnetic heading information to the systems is much smaller than those domes.



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If you are referencing the heading indicator when talking about a gyrocompass those are panel mounted. If you are referencing the wet compass (which is balanced in fluid) those are mounted on the column in the center of the windshield typically. A lost of the more modern aircraft in this class have glass panels which use AHARS units and may not have traditional gimbals anymore.