The XF1 set consists of four magnetic field probes and one E-field probe for measuring E-fields and magnetic fields from 30 MHz to 6 GHz on electronic assemblies during the development stage. Due to their integrated impedance matching, the probes are less sensitive in the lower frequency range than the RF-type probes. The probe heads of the XF1 set allow for the step by step localization of magnetic-field interference sources on assemblies. First the XF-R 400-1 probe is used to detect electromagnetic interference from greater distances. Next, the higher resolution probes can be used to more precisely detect the interference sources. The E-field probe is used for the detection of electric interference fields near the assemblies. With trained use of the near-field probes, field orientation and field distribution can be detected. The near-field probes are small and handy. They have a current attenuating sheath and, therefore, are electrically shielded. They can be connected to a spectrum analyzer or an oscilloscope with a 50 Ω input. They have an internal terminating resistance.