Do magnetic fields affect the indications of a multimeter?
The answer is yes, if the multimeter is analog since the movement of the needle is determined by the interaction of the field of a beret with the field of a permanent magnet. A strong magnet near the multimeter may influence the field responsible for the movement of the coil and hence the needle. It is recommended that the Meter never be positioned near speakers that have strong magnets, motors with permanent magnets when used, as their accuracy in the indication may be affected. Already, digital multimeters do not have this problem, but their circuits can be influenced by strong electric fields such as motors, transformers and even created by coils driven by intense currents. RF signals may also influence the measurements of a multimeter if they are picked up by the cables.
