B&K Precision 2658A - Manual - Manual (Page 58)

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20.2 EMI Test
The QP detection is usually used in both of the radiated and conducted emission measurements, and the AV
detection is usually used in the conducted emission measurement. The measurement time can be shortened by
using them in the final measurement to the spectrums narrowed by the PK detection.
Conducted Emission Measurement
The conducted emission discharged through the power supply line is measured.
In this measurement, LISN* (Line Impedance Stabilization Network) device is needed.
The connection is shown in the figure below. Please refer to the manual of LISN for details of the
connection and notes.
1. Turn on the power of the 2651 after the connection.
2. Set the initial parameters of conducted emission measurement by pushing
. The setting parameters are as follows.
Center Frequency : 25.5 MHz
Frequency span : 50 MHz
RBW : 9 kHz
VBW : 1 MHz
Sweep time : 3 sec
Detection mode : Positive peak mode
3. Confirm whether the connection and the operation are correct by supplying the power to the EUT and
measuring.
4. Set the number of times of the sweep in the MAX HOLD mode by operating
.
5. Search the frequency of disturbance noise that exceeds the AV or QP limits by using the marker
function.
6. Set the center frequency to the point that exceeds the limits, the SPAN to 2 MHz and the SWEEP to
0.1 sec. And measure the frequency accurately.
Power Supply
EUT
2651
LISN *
F6 SAVE/LOAD F2
F2 CALC