Platten- und Peilkompass

A plate compass (also called a marching compass) consists of a transparent base plate and a rotatable compass housing. Its function is based on the interaction of a magnet needle, a housing scale, and orientation lines to align a map with the terrain or to follow a course.

Key components and their role

• Base plate: A transparent acrylic plate with a edge (often with a ruler/scale) and a fixed sighting arrow (course arrow) that always points in the direction of travel.

• Magnet needle: The two-color needle aligns freely with the Earth's magnetic field (the red end points to magnetic north).

• Orientation arrow & lines: An arrow drawn on the bottom of the rotatable housing ("north arrow" or "north roof") that rotates with the scale.

1. Orienting the map:

Place the edge of the compass on a north-south line on the map. Rotate the compass housing so that the orientation arrow points north on the map. Now rotate the entire compass along with the map until the red magnet needle is exactly in the orientation arrow.

2. Determining the course (azimuth):

On the oriented map, place the edge of the compass from your current location to the destination. Rotate the compass housing until the orientation arrow is parallel to the north lines on the map. The value at the reading mark is the course angle.

3. Navigating in the terrain:

Hold the compass horizontally in front of your body so that the sighting arrow points forward. Rotate yourself until the red magnet needle clicks exactly into the orientation arrow ("north in the north roof"). The sighting arrow now points directly to the destination.

Note: Interference factors

Keep the compass away from metallic objects, smartphones, power lines, or knife blades during measurement - these deflect the magnet needle and distort the result.