DOWNLOAD JBL ENCOUNTER (serv.man5) Service Manual ↓ Size: 2.73 MB | Pages: 79 in PDF or view online for FREE

Nemko USA, Inc. 

 

This test measures the levels emanating from the EUT, thus evaluating the potential for the EUT to cause 
radio frequency interference to other electronic devices.  Testing was performed in accordance with the test 
standard(s) referenced in the test summary section of this report.  The Equipment Under Test (EUT) was 
configured based upon the requirements of the applicable test standard. 

Nemko USA, Inc. 

 

1.  Test Laboratory (6 X 6 meters) 
2.  Ground Plane (15 square meters) 
3.  Vertical Conducting Wall (Grounded through Ground Plane via 10' ground rod) 
4.  AC Power for Devices  
5.  Power Line Filter, Lindgren, 120 dB, 30 amp 
6.  Artificial Mains Network (AMN) for peripheral devices 
7.  Power Distribution Box for peripheral devices 
8.  Spectrum Analyzer with Quasi-Peak Adapter 
9.  High Pass Filter 
10.  Coax input from EUT AMN to Spectrum Analyzer 
11.  AMN for EUT 
12.  EUT and Associated System 

 

8 

7 

40 cm

9 

4 

1 

2 

3 

6 

5 

11

12 

13 

10 

Nemko USA, Inc. 

 
 

 

This test measures the levels emanating from the EUT, thus evaluating the potential for the EUT to cause 
radio frequency interference to other electronic devices.  Testing was performed in accordance with the test 
standard(s) referenced in the test summary section of this report.  The Equipment Under Test (EUT) was 
configured based upon the requirements of the applicable test standard.  Initially, the primary emission 
frequencies are identified inside a shielded chamber by positioning a broadband receive antenna one meter 
from the EUT.  Next, the EUT and associated system are placed on a turntable on a ten-meter open area test 
site (OATS) with known attenuation characteristics and all significant radiated emissions are recorded.  To 
ensure that the maximum emission at each discrete frequency of interest is observed, the receive antenna is 
varied in height from one to four meters and rotated to produce horizontal and vertical polarities while the 
turntable is rotated to determine the worst emitting configuration.  The numerical results are included herein to 
demonstrate compliance. The numerical results of the test are included herein to demonstrate compliance.   

 

The numerical results that are applied to the emissions limits are arrived at by the following method: 
Example: A=RR+CL+AF 
A = Amplitude dBuV/M 
RR = Receiver Reading dBuV 
CL = cable loss dB 
AF = antenna factor dBm-1 
Example Frequency = 110MHz 
18.5 dBuV (spectrum analyzer reading) 
+3.0 dB (cable loss @ frequency) 
21.5 dBuV 
+15.4 dBm-1 (antenna factor @ frequency) 
36.9 dBuV/M Final adjusted value 
The final adjusted value is then compared to the appropriate emission limit to determine compliance. 

Nemko USA, Inc. 

Figure 2.   Radiated Emissions Test Setup Diagram 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 

 
1.  Ground plane (11 X 17 meters) 
2.  Spectrum Analyzer with Quasi-Peak Adapter 
3.  Coax interconnect from Receive Antenna to Spectrum Analyzer 
4.  Antenna Mast with motorized mounting assembly 
5.  Receive Antenna (basic relative position) 
6.  Non-Conducting table 80 cm above ground plane 
7.  DC power for devices 
8.  EUT and Associated System 
 

1

 

2

 

3

 

4

 

1 to 4 
meters 

10 meters

5

 

6

 

7

 

8