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A near-field probe has finite dimensions. Slight repositioning of the
probe vs. the device under test (DUT) may put the near-field antenna in
a place where the geometry of the DUT alters field strength readings,
thus rendering repeatability of the measurements next to impossible.
There are just too many variables to make the numerical results of near-field
tests trustworthy. If the readings taken with a near-field probe cannot be
trusted, what are the benefits of using it? This question may especially be of
interest to those engineers used to precision in measurements. The answer
is simple: a near-field test, regardless of the test equipment used, provides
only relative results. The near-field test can show where the emission is
stronger and where it is weaker, and what type of field is dominant (i.e. what
specifically is causing it). The 3M
™
ScanEM-C Electromagnetic Near-Field
Probes can locate the source of the offending radiation, saving days or even
weeks and a substantial amount of money in unnecessary trial-and-error
testing in an agency-certified laboratory. The ScanEM-C Probes have a high
detection capability, and depending on circumstances, can narrow problem
areas down to a single component or trace.
