Electromagnetic Field (EMF) MeasurementsOption 444 : Spectrum Analyzer : Measurement Results
Measurement Results
After completing the data collection for the three axes, the Isotropic Result is calculated and displayed. In addition to the three traces displayed on the user interface (Axis Sweep Data, Current Isotropic Result, and Average Isotropic Result/Measurement), the max, min, and average values of the Isotropic Result traces are also computed and displayed in the table below the graph region. See Figure: EMF Measurement Display. The average value is computed as:
sum of the 551 trace point amplitudes / 551
The Current row displays values computed for all measurements completed thus far, as indicated by Measurement Number (2/5, for example) at the bottom of the table. At the end of the specified measurement time, the current max, min, and average values are copied to the Total row. The Current row is then cleared for the next measurement. The Isotropic Results are updated until the set number of measurements have completed or you stop the measurements by pressing the Measurement On/Off key.
EMF Measurement Display
The limit check is done at the end of each measurement and determines the Pass/Fail status of the tests. The limit line, if selected, is applied against the Iso Avg trace. To show or hide the Current Test Status and Final Test Result, press the Limits submenu key in the EMF menu (see Figure: EMF Menu), then press the On/Off key.
At the end of the specified measurement time and if the trace exceeds the selected limit, a FAIL is recorded and the Current Test Status in the summary table is updated to FAIL. In that case, the Final Test Result is immediately displayed as a FAIL. If the Average Isotropic Result does not cross the limit line, then the Current Test Status is updated to PASS and stays this way for a few sweeps. The Current Test Status is then updated to “--”. See Figure: EMF Measurement Display. If all of the measurements pass, the Final Test Result is updated to PASS. See Figure: EMF Test Pass/Fail Status.
If Auto Logging is set to On prior to starting the measurements, Pass/Fail results are saved in a log file with the Isotropic Results. Refer to EMF Auto Menu.
EMF Test Pass/Fail Status