• b-dot probe
• calibration
• helicon thruster
• helicon wave
• Helmholtz coil
• network analyzer

In this work, a B-dot probe was studied, designed, built, and employed to measure the time-varying magnetic field within the plume of a Helicon thruster. The probe was manually constructed and calibrated using a network analyzer. The experiments have been done in a vacuum chamber on the prototype HPT05M and the various measurements have been taken using an oscilloscope. Following the experimental part, the collected data were processed to determine with a specific code to get the intensity and direction of the magnetic field at various positions within the plume.