SparkFun Forums

[ryan]

What is the difference between a magnetometer and a compass (e.g CMPS03)?

[phalanx]

Just taking a quick guess as I haven't looked at either of the parts but I would expect a magnitude and direction from a field measurement using a magnetometer.

From a compass, I would only expect a direction.

-Bill

[OldCow]

Bill is right.

In the good old days, compass is an instrument to show direction - the direction of magnetic north (or south). It is used for navigation and things like that. It shows the direction of the horizontal component of earth’s magnetic field. It does not care about the magnitude of the magnetic field, and it does not care about the vertical component.

Magnetometer is a different kind of instrument. It mainly shows the magnitude of the magnetic field. It is used to locate iron deposit, shipwrecks, or solar winds and things like that.

But nowadays, I do not know which is which. They take garbage from slaughterhouse and put them in little cans and call them cat food. They put the same stuff in bigger cans and call them dog food. What’s the difference?