SPARK (serv.man10) - JBL Audio EMC - CB Certificate (repair manual). Page 8

Report No.:  EM201300221-6

  

                       Application No.: ZJ00028648                      Page 8 of 19 

 

 

Frequency (MHz) 

Quasi-peak(dBµV/m) 

30 ~ 88 

40 

88~216 43.5 

216 ~ 960 

46 

Above 960 

54 

NOTE: (1) The lower limit shall apply at the transition frequencies. 

According to ANSI C63.10:2009, a calibrated, linearly polarized antenna shall be positioned 
at the specified distance from the periphery of the EUT. The specified distance is the distance 
between the horizontal projection onto the ground plane of the closest periphery of the EUT 
and the projection onto the ground plane of the center of the axis of the elements of the 
receiving antenna. 

Measurements shall be made with the antenna positioned in both the horizontal and vertical 
planes of polarization. The measurement antenna shall be varied in height above the reference 
ground plane to obtain the maximum signal strength. Unless otherwise specified, the 
measurement distance shall be 3 m. At any measurement distance, the antenna height shall be 
varied from 1 m to 4 m. These height scans apply for both horizontal and vertical 
polarizations, except that for vertical polarization, the minimum height of the center of the 
antenna shall be increased so that the lowest point of the bottom of the lowest antenna 
element clears the site reference ground plane by at least 25 cm. For a tuned dipole, the 
minimum heights as measured from the center of the antenna are those specified in the NSA 
measurement requirements. 

For tabletop systems, cables or wires should be manipulated within the range of likely 
arrangements. For floor-standing equipment, the cables or wires should be located in the 
same manner as the user would install them and no further manipulation is made. For 
combination EUTs, the tabletop and floor-standing portions of the EUT shall follow the 
procedures for their respective setups and cable manipulation.  

Table-top equipment is placed on a non-conductive set-up table with height 0, 8 m ± 0, 01 m, 
ANSI C63.10:2009 specifies the method to determine the impact of the non-conductive 
set-up table on test results. If the manner of cable installation is not known, or if it changes 
with each installation, cables or wires for floor-standing equipment shall be manipulated to 
the extent possible to produce the maximum level of emissions. For each mode of operation 
required to be tested, the frequency spectrum shall be monitored. Variations in antenna height 
between 1 m and 4 m, antenna polarization, EUT azimuth, and cable or wire placement shall 
be explored to produce the emission that has the highest amplitude relative to the limit.