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Report #70112.e1 

 
 

 

Radiated/Site 1 - A 

 

 

 

145-006 

BiLog Antenna 
(30 MHz to 2 GHz) 

Chase CBL6112A 

2284 

7-21-05 

145-001 

Spectrum Analyzer 
(9 KHz to 22 GHz) 

HP8593E 3543A01976 

3-26-05 

145-092 

EMI Receiver 
(9 KHz to 2.9 GHz) 

HP8542E 6906A00273 

11-26-04 

145-013 

Preamplifier 
(150 KHz to 1.3 GHz) 

HP 8447D 

2944A07027 

11-5-04 

145-082 Cable 

Rosenberger 

N/A 

1-23-05 

145-083 Cable 

Rosenberger 

N/A 

1-23-05 

145-084 Cable 

Rosenberger 

N/A 

1-23-05 

High Frequency Setup/site 1 – B 

 

 

 

145-029 

Guided Ridged Horn 
(1 GHz to 18 GHz) 

EMCO 3115 

5520 

8-5-05 

145-020 

Preamplifier 
(1 GHz to 26.5 GHz) 

HP 8449B 

3008A00948 

10-10-04 

145-092 

EMI Receiver 
(9 KHz to 2.9 GHz) 

H-P85422E 6906A00273 

11-26-04 

145-084 Cable 

(28ft.) 

Rosenberger 

N/A 

1-23-05 

145-083 Cable 

(10ft.) 

Rosenberger 

N/A 

1-23-05 

Conducted/Site1 – C 

 

 

 

145-001 

Spectrum Analyzer 
(9 KHz to 22 GHz) 

HP8593E 3543A01976 

3-26-05 

145-008 

LISN:  50

Ω/50µH 

 

Solar 
9252-50-R-24-BNC 

971601 8-24-04 

145-005 

LISN:  50

Ω/50µH 

 

Solar 
9252-50-R-24-BNC 

941725 7-30-05 

145-075 Cable 

RG58/U 

N/A 

9-22-04 

by the National Institute of Standards and Technology (NIST). 

Report #70112.e1 

 
 

 

 

The purpose of this test is to measure the radiated electromagnetic emissions generated by the 
equipment under test (EUT), pursuant to FCC part 15 and EN55022 Class B requirements. (See 
Table 3.1.1-1 for the Class B radiated limits.) 
 

Testing is performed in an Open Area Test Site. The EUT is placed on a wooden turntable 80 cm 
in height. The EUT is centered laterally on the turntable and flush with the rear of the table. 
Peripheral equipment is placed on either side of the EUT with a minimum of 10 cm spacing. 
(When testing a personal computer system, monitors shall be placed on top of the PC, and the 
keyboard and mouse shall be placed in front of the PC towards the front edge of the turntable.) 
Excess interface cables are draped over the back edge of the table no closer than 40 cm to the 
ground plane. 

 

The EUT shall be set into operation such that all parts of the system are exercised. This may 
require the use of test software designed to exercise the various parts of the system. With the EUT 
set into operation, the turntable is rotated over 360 degrees and interface cables are manipulated 
to maximize the emissions. The peripherals are not moved during the test. The receiving antenna 
is placed at a test distance of 3 or 10 meters from the closest point on the EUT. The antenna 
height is varied from 1 to 4 meters, and the polarity of the antenna is switched between vertical 
and horizontal such that the received signal is maximized. 
 

 

None 
 

A minimum of a 2 dB margin of compliance is recommended for radiated emissions data to verify 
passing results. This is recommended to compensate for the measurement uncertainties involved. 

Report #70112.e1 

 
 

The Digital Controller met the FCC and EN55022 Class B radiated emissions requirements when 
tested as described below. (See Test Data for a complete listing of data points.) 
 
Worst-case emissions measured: 

See Note (1) 

Passed:  - 2.94 dB at 393.2 MHz 

Line Voltage: 120 VAC, 60 Hz 

See Table: A1 

Azimuth Angle (see diagram below): 

180º 

Antenna Height: 2 Meter(s) 

Polarity: Vertical 

Passed:  - 3.94 dB at 393.2 MHz 

Line Voltage: 120 VAC, 60 Hz 

See Table: A1 

Azimuth Angle (see diagram below): 

180º 

Antenna Height: 2 Meter(s) 

Polarity: Vertical 

 
Notes 
 
 

(1) 

Final scan. No modifications installed. 

 
 

Azimuth Angle Diagram 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
The above results pertain only to the specific item submitted for testing, identified by the 
product’s model and serial numbers. 

EUT

Front

Rear

45° 

135°

180°

225°

270° 

315

0°

90°

Report #70112.e1 

 
 

 
The following is a description of terms and a sample calculation, as appears in the radiated 
emissions data table. The numbers used in the calculation are for example only. There is no direct 
correlation to the specific data taken for the product described in this document: 
 
Reading:  This is the reading obtained on the spectrum analyzer in dB

µV. Any external 

preamplifiers used are taken into account through internal analyzer settings. 

 
A.F.: 

This is the antenna factor for the receiving antenna. It is a conversion factor, which 
converts electric fields strengths to voltages, which can be measured directly on the 
spectrum analyzer. It is treated as a loss in dB. Cable losses have been included with 
the A.F. to simplify the calculations. The antenna factor is used in calculations as 
follows: 

 
 

 

µ

µ

V/m) 

 
Net: 

This is the net field strength measurement (as shown above). 

 
Limit: 

This is the FCC Class B radiated emission limit (in units of dB

µV/m). 

 
Margin:  This is the margin of compliance below the FCC limit. The units are given in dB. A 

negative margin indicates the emission was below the limit. A positive margin indicates 
that the emission exceeds the limit. 

 
Example for an emission measuring 20.5 dB

µV on the spectrum analyzer at 592 MHz: 

(Note: This shows a passing result (i.e. a negative margin)) 
 
Example only: 
 

Reading A.F. 

    Net Reading           Net Reading      FCC limit             Margin 

20.5dB

µV   +    25 dB    =  45.5 dBµV/m   :   45.5 dBµV/m  -  57 dBµV/m =     -11.5 dB