# How to Calibrate a Magnetic Compass

A sailor can never go out to sea without a compass as they have been used for centuries as a directional and navigational tool. A compass is an indication device that adjusts itself to the magnetic field of the Northern Post of the World, thereby indicating north. The magnetic Northern Pole and regional Northern Pole of the World are different and not at the same point either. A compass must align itself to the magnetic North Pole and not the regional Northern Pole. If you are wondering how a compass is calibrated then consider following some simple instructions given below.

### Instructions

• 1

Course-plotting is the system used by sailors and mariners across the world to plot their course using a compass, along with maps, charts and other computation techniques. A normal compass is an indication of the route, but there can be modifications and diversions involved with respect to the exact place. However, compass users can determine the distance traveled and the time spent in the ocean with the magnetic sources. Today’s compasses include an additional signal to demonstrate the route of travel.

• 2

Compass Design

The working design of a compass contains the following components:

a) Magnetic hook, which is an arrow-shaped magnet in the direction of earth’s electric northern pole.

b) Needle device, on which the hook is properly secured in place.

c) Switch and dial points, which display the four cardinal directions.

• 3

Calibration with map

Due to northern electric pole modifications and effects, a compass may require calibration and modification to eliminate difference, based on where it is used. Magnetic compasses always point in the direction of magnetic north pole which is of course not the same as the regional Northern Post. Studies have shown that the difference between these two points is around 1000 miles and it depends on the location where the compass is used. Hence almost all electric compasses are required to be modified or calibrated while using a map which reveals the regional points.

• 4

Calibrating electronic compasses

Electronic compasses are modified with the help of receptors and other tools for calibration, along with a software program which uses information from systems known as milestone positions and the physical parts of the receptors to map the difference along with a gyroscope. The values generated by the software program are entered into the electronic compass for correction.