Radio Shack AA0120495, Application

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INTERTEK TESTING SERVICES
FCC ID: AAO120495 9
3.1 Field Strength Calculation
The field strength is calculated by adding the reading on the Spectrum
Analyzer to the factors associated with preamplifiers (if any), antennas,
cables, pulse desensitization and average factors (when specified limit is in
average and measurements are made with peak detectors). A sample
calculation is included below.
FS = RA
+
AF
+
CF
−
AG
+
PD
+
AV
where FS = Field Strength in dB
µ
V/m
RA = Receiver Amplitude (including preamplifier) in dB
µ
V
CF = Cable Attenuation Factor in dB
AF = Antenna Factor in dB
AG = Amplifier Gain in dB
PD = Pulse Desensitization in dB
AV = Average Factor in
−
dB
In the radiated emission table which follows, the reading shown on the data
table may reflect the preamplifier gain. An example of the calculations, where
the reading does not reflect the preamplifier gain, follows:
FS = RA
+
AF
+
CF
−
AG
+
PD
+
AV