ETS-Lindgren 7405 E & H Near Field Probe Set - Manual (Page 45)

www.ets-lindgren.com Common Diagnostic Techniques 45
2. The probe becomes part of the circuit during near-field measurements.
There is capacitance and inductance between the circuit being
measured and the probe with the associated cabling. The probe will
re-radiate the received field, altering the field being measured.
However, technical imprecision does not necessarily eliminate a method.
Sometimes an attenuation of the field strength in the near-field will translate into
an attenuation of the far-field reading. As long as a linear relationship is not
expected, there can be real benefit from near-field probing. Generally, a
reduction of the non-radiating field will also mean that the radiating field has been
reduced.