The search coil comprises a 3,300 turn coil with an air core, connected to flying leads terminating in 4mm plugs. It is used to measure varying magnetic fields. When the axis of the coil is held perpendicular to the varying magnetic field, a voltage is induced in the coil, which can be measured using a sensitive voltmeter, or observed on an oscilloscope.Requirements:AC millivoltmeter, or Oscilloscope, or DC voltmeter with rectifying diodeApplications:Measuring varying magnetic fieldsTransformer investigation