Digital compass.

 

1) Solid state Hall effect device that can measure earth's magnetic field

2) Each cardinal direction has an transistor output that switches on when facing correct direction. Intermediate direction such as southwest (for example) can be determined when both south and west (for example) transistor are on.

2) Should not be tilted more than 12 degrees, as this will confuse the sensor.

 

 

 

 

 

 

 

 

 

 

 

 

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