3M ScanEM-QC CTK019, Руководство пользователя

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Monitoring the Signals
You can monitor the signal on cables or wires without contact with the 3M
™
ScanEM-HQC Electromagnetic Near-Field Probe. Connect the output of
the ScanEM-HQC Probe to an oscilloscope. Set the scope input coupling
to AC. Place the cable or wire in the groove of the ScanEM-HQC Probe
sensor and observe the waveform of the signal on the screen. Keep in mind
that the waveform of the electromagnetic field is different from that of the
cable itself. You won’t be able to measure distortion of the signal nor will
you be able to precisely assess undershoot/overshoot of pulses. However you
should be able to reliably detect the signal, estimate its waveform, measure
the frequency of the signal, for example—all without influencing the signal.
This is especially important where direct contact with the circuit disrupts its
normal operation or is dangerous.
Locating Bad Connections
The ScanEM Probe can help in locating bad connections and broken traces
by showing sharply different radiation levels and patterns before and after
the connection in question.
Identifying Cables and Wires Carrying RF Signals
By monitoring radiation patterns of individual cables or wires in a live
product, you should be able to check whether that cable or wire is connected
properly. The ScanEM Probe can save you hours of guesswork.