A test and measurement instrument, comprising at least one port configured to receive a signal from a device under test; a user interface configured to receive a user input, the user input indicating magnetic properties of a magnetic material of the device under test, and one or more processors. The one or more processors are configured to generate a hysteresis loop mask based on the magnetic properties of the magnetic material, determine whether the signal received from the device under test violates the hysteresis loop mask, and generate an alert when the signal received from the device under test violates the hysteresis loop mask. The test and measurement instrument may also include a display configured to display the hysteresis loop mask, the signal received from the device under test, and/or the alert.