3M ScanEM-C, Руководство пользователя

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the right. This chart is provided for reference only. Specification is subject to
change without notice.
Know What You are Measuring
Î A word of caution: Avoid misleading numerical readings of the field strength
by understanding what you are actually measuring. The 3M
™
ScanEM-C
Electromagnetic Near-Field Probe measures the field strength at its tip. In the
near-field the field strength fluctuates dramatically depending on the distance
from the source. Slight repositioning of the tip of the ScanEM-C Probe may
result in different readings.
What You Can Do With the ScanEM-C Probe
Measuring Shielding Efficiency
Measure the field strength before and after the shield is applied to know the
actual effectiveness of the shielding. Measuring the field strength on both
sides of the shield also helps to evaluate shielding.
The ScanEM-C Probes and a multimeter can be used to check the quality of
applied shielding and gaskets in production. A quality control inspector can
be supplied with the maximum allowed DC voltage at critical points.
Locating Defective Components
Often one doesn’t need a spectrum analyzer in order to locate
malfunctioning ICs and other components. The strength of the emitted field
next to the component can be a good indicator of its status.
EMC Pre-Compliance and Troubleshooting
Connect the ScanEM-C Probe to the input of the spectrum analyzer. Set the
spectrum analyzer to the desired settings (if in doubt, use default settings
on power-up). Press and hold the red Operate button. Pass the tip of the
ScanEM-C Probe over the area in question. Should the emission level be too
high, you may need to change the attenuation of the spectrum analyzer’s input.