Read JBL SPARK (serv.man8) EMC - CB Certificate online
Report No.:
EM201200813-7
Application No.:
ZJ00024740
Page 21 of 47
4.2 DISTURBANCE POWER MEASUREMENT
4.2.1 LIMITS
FREQUENCY (MHz)
dBpW
Quasi-peak(dBpW)
Average(dBpW)
30 ~ 300
45 to 55 (a)
35 to 45 (a)
Note: (a) Increasing linearly with the frequency.
4.2.2 TEST PROCEDURES
The appliance to be tested is placed on a non-metallic table at least 0,4 m from other metallic
objects and the lead to be measured on is stretched in a straight line for a distance sufficient to
accommodate the absorbing clamp, and to permit the necessary measuring adjustment of
position for tuning. The clamp is placed around the lead so as to measure a quantity
proportional to the disturbance power on the lead.
The absorbing clamp is positioned for maximum indication at each test frequency: the clamp
shall be moved along the lead until the maximum value is found between a position adjacent
to the appliance and a distance of about a half-wavelength from it.
The straight portion of the lead to be measured on should therefore be about 6 m long, this
being equal to λ max/2 + 0,6 m in order to allow at any time the positioning of the absorbing
clamp and a possible second clamp for additional isolation. Pre-testing is carried out in all
operating modes to find the worst mode for the every test terminal.
4.2.3 TEST SETUP
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