COM-power corporation AL-RE101 User manual

Page 1 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
INSTRUCTION MANUAL
for
LOOP ANTENNA
Model: AL-RE101

Page 2 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

- TABLE OF CONTENTS -
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
Table of Contents
1.0 Introduction ........................................................................................................... 4
2.0 Products Available from Com-Power ................................................................. 5
3.0 Product Information .............................................................................................. 6
3.1 Incoming Inspection............................................................................................................... 6
3.2 Package Inventory ................................................................................................................. 6
3.3 Product Features ..................................................................................................................... 7
3.4 Product Specifications............................................................................................................ 8
4.0 Using Your AL-RE101 Loop Antenna .................................................................... 9
4.1 Antenna Conversion Factors................................................................................................ 10
4.1.1 Interpolation of Antenna Conversion Factors ........................................................... 12
5.0 Antenna Theory................................................................................................... 13
5.1 Open Circuit Antenna Terminal Voltage vs Flux Density ................................................... 13
5.2 Determination of Antenna Conversion Factors .................................................................. 15
5.2.1 Derivation of Antenna Conversion Factor Equation ................................................ 17
6.0 Calibration and Calibration Cycle.................................................................... 19
6.1 Calibration Equipment.......................................................................................................... 19
6.1.1 Source Equipment.......................................................................................................... 20
6.1.2 Measuring Instruments ................................................................................................... 20
6.1.3 Transmitting Loop Antenna........................................................................................... 20
6.1.4 Precision 1-ohm Series Resistor ..................................................................................... 20
6.1.5 RF Current Probe ............................................................................................................ 20
6.2 Interpretation of Standards................................................................................................... 21
6.3 Calibration Methodology ..................................................................................................... 22
7.0 Warranty............................................................................................................... 24
8.0 Maintenance....................................................................................................... 25
9.0 Typical Performance Data ................................................................................. 26

Page 3 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

- LIST OF FIGURES -
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
List of Figures
FIGURE 1 - AL-RE101 Features 7
FIGURE 2 - AL-RE101 Loop Antenna Dimensions 8
FIGURE 3 - Typical Test Arrangement 9
FIGURE 4 - Antenna Conversion Factors 10
FIGURE 5 - Typical Measurement Setup for Calibration (1Resistor Method) 19
FIGURE 6 - Typical Measurement Setup for Calibration (Current Probe Method) 19

Page 4 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 1 - INTRODUCTION
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
1.0 Introduction
This manual includes descriptions of product features; product specifications, safety
precautions, operational instructions, antenna theory, measurement guidelines, warranty
and product maintenance information.
Information contained in this manual is the property of Com-Power Corporation. It is
issued with the understanding that the material may not be reproduced or copied
without the express written permission of Com-Power.

Page 5 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 2 - PRODUCTS AVAILABLE FROM COM-POWER
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
2.0 Products Available from Com-Power
www.com-power.com

Page 6 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 3 - PRODUCT INFORMATION
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
3.0 Product Information
3.1 Incoming Inspection
Please check the contents of the shipment against the package inventory in
section 3.2 to ensure that you have received all applicable items.
3.2 Package Inventory
STANDARD ITEMS:
•AL-RE101 Loop Antenna
•Calibration Data and Certificate

Page 7 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 3 - PRODUCT INFORMATION
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
3.3 Product Features
FIGURE 1 - AL-RE101 Features
Antenna Output Port
1
Coaxial BNC port for connection to input port of measuring instrumentation.
7 cm Spacing
2
The 7 cm spacing required for MIL-STD 461, RE101 is achieved when the front edge of the
plexi-glass bottom plate of the antenna assembly is positioned perpendicularly against the
EUT surface.
Loop Coil
3
Contained within the electrostatic shield is the loop coil consisting of 36 turns of 41 gauge,
7-strand Litz wire.
Electrostatic Shield
4
The powder coated metallic structure housing the loop coil serves as the electrostatic shield
for the loop.
7 cm
2
1
3
4

Page 8 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 3 - PRODUCT INFORMATION
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
3.4 Product Specifications
Frequency Range 30 Hz to 100 kHz (usable range: 10 Hz to 1 MHz)
Standard(s) MIL-STD-461, RE101
Loop Diameter (outside) 13.3 cm (5.24 in.)
Number of Turns (N) 36 Turns
Wire Type 7 Strand, 41 AWG Litz Wire
Loop Shielding Electrostatic Shield
Resistance of Loop Coil (RC)10Ω(nominal)
Inductance of Loop Coil (L) 340 μH (nominal)
Connector Coaxial BNC (female)
Weight 0.84 lbs. (0.38 kg)
Operating Temperature 40°F to 104°F (5°C to 40°C)
FIGURE 2 - AL-RE101 Loop Antenna Dimensions
(W) 6”
15.35 cm
4.5”
11.5 cm
(L) 3.8”
9.7 cm
0.66”
1.66 cm
AL-RE101
LOOP ANTENNA
30 Hz to 100 kHz
4.5”
11.5 cm (H) 7.48”
19 cm
6”
15.35 cm
4.5”
11.5 cm (H) 7.48”
19 cm
6”
15.35 cm
2.8”
7 cm

Page 9 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 4 - USING YOUR AL-RE101 LOOP ANTENNA
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
4.0 Using Your AL-RE101 Loop Antenna
The AL-RE101 Loop Antenna should be connected directly to the input port of the
measuring instrument(s). Follow the procedures described in the applicable standard for
the test(s) to be performed.
FIGURE 3 - Typical Test Arrangement
Generally, the AL-RE101 Loop Antenna is intended to be positioned at a 7 cm distance
from the Equipment Under Test (EUT). Due to the small size of the loop coil, its close
proximity to the EUT, and also depending on the size of the EUT, the magnetic field pick-
up of the AL-RE101 Loop Antenna may be sensitive to small movements over the surfaces
of the EUT.
Therefore, as described in MIL-STD-461, the antenna position should be slowly scanned
over the face of the EUT and around the connectors, in order to find the point(s) of
maximum radiation.
LISN
EUT
Power
Input
Measurement
Instrument
AL-RE101
Loop Antenna
7 cm

Page 10 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 4 - USING YOUR AL-RE101 LOOP ANTENNA
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
4.1 Antenna Conversion Factors
Your AL-RE101 Loop Antenna is provided with two sets of antenna conversion
factors. The input impedance of your measuring instrument determines which
factor to use, as described below.
The 50 ohm antenna conversion factors are the most commonly applied. These
are to be used when the AL-RE101 Loop Antenna is connected to a measuring
instrument having a nominal input impedance of 50 ohms. These factors are
provided over the frequency range of 10 Hz to 1 MHz, as shown in Figure 4. To
find the factors for frequencies between those listed on the table, see section
4.1.1.
The 100 kfactors are used when the AL-RE101 Loop Antenna is connected to a
measuring instrument with a high input impedance (greater than approximately
500 ohms). These factors are provided over the truncated frequency range of 10
Hz to 50 kHz, also as shown in Figure 4. The antenna should generally not be used
above 50 kHz without a 50 ohm termination.
FIGURE 4 - Antenna Conversion Factors
Antenna Type Loop Antenna
Model AL-RE101
FREQUENCY
100 kΩ 50Ω
(kHz) [dBpT/μV] [dBpT/μV]
0.01 90.1 91.6
0.02 84.1 85.7
0.03 80.5 82.1
0.05 76.1 77.7
0.1 70.1 71.7
0.2 64 65.6
0.3 60.6 62.2
0.5 56.1 57.7
150.151.7
244.145.7
340.542.2
536.137.8
10 30.1 32.2
20 24.1 27.4
30 20.5 25.4
50 16.2 23.9
100 23
200 22.8
300 22.7
500 22.7
1000 22.7
ANTENNA CONVERSION FACTORS

Page 11 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 4 - USING YOUR AL-RE101 LOOP ANTENNA
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
The antenna conversion factor (in dBpT/V units) is to be added to the measured
value (in dBV) to obtain the corrected magnetic field strength value, or flux
density (in dBpT).
EXAMPLE CALCULATION #1:
An EUT emission is identified at a frequency of 500 Hz, with a measured value of
40 dBμV, or 100 μVon a measurement instrument having a nominal input
impedance of 50.
Using the table shown in Figure 4, the 50antenna conversion factor at 500 Hz is
57.7 dBpT/V; therefore:
The magnetic field strength, or flux density, is 97.7 dBpT.
=
+
57.7
dBpT/μV
40.0
dBμV
97.7
dBpT
EQUATION (1)
Magnetic
Field Strength
(in dBpT)
=
Measured
Value
(in dBμV)
Antenna
Conversion
Factor
(in dBpT/μV)
+

Page 12 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 4 - USING YOUR AL-RE101 LOOP ANTENNA
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
4.1.1 Interpolation of Antenna Conversion Factors
In order to find the antenna conversion factor (ACF) for frequencies
between those listed in the table, Equation (2) may be used for
interpolation:
EXAMPLE CALCULATION #2:
In this example, the 50 ohm antenna conversion factor at 60 Hz is
calculated. Using the Figure 4 table, the following values are known:
Frequency
Antenna
Conversion
Factor (50Ω)
ƒ150 Hz ACF177.7 dBpT/V
ƒ2100 Hz ACF271.7 dBpT/V
Using Equation (2), the antenna conversion factor at 60 Hz is calculated as
ACFx:
EQUATION (2)
where:
ACF = unknown antenna conversion factor at
ƒ
XX
ACF = antenna correction factor at ƒ
22
ACF = antenna correction factor at ƒ
11
ƒ = frequency at which antenna conversion factor is desired
X
ƒ = frequency just below ƒ
1X
ƒ = frequency just above ƒ
2X
ACF = ACF + (ACF - ACF )
X
log( ƒ /ƒ )
X1
log( ƒ /ƒ )
21
121
( )
ACF = 77.7 + (71.7 - 77.7)
X
log( 60/50)
log( 100/50)
(
)
ACF = 76.1 dBpT/μV
X
dBpT/μV

Page 13 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 5 - ANTENNA THEORY
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
5.0 Antenna Theory
This section details the theoretical operation of the AL-RE101 loop antenna. Equation (3)
through Equation (7) define the relationship between the average magnetic field
strength (or magnetic flux density) within the area of the loop coil and the voltage
present at the antenna terminals, in order to determine the antenna conversion factors.
These equations consider the physical and electrical characteristics for the antenna, as
shown in the following pages.
5.1 Open Circuit Antenna Terminal Voltage vs Flux Density
Equation (3) below defines the relationship between open circuit loop terminal
voltage, number of turns in the coil, area of the coil, the frequency and the
average flux density within the area of the coil:
Equation (3) is resolved below by substituting the actual number of turns (N) and
coil area (A) for the AL-RE101 Loop Antenna; and to provide the resultant
quantity in microvolts (rather than volts).
EQUATION (4)
e = 2πNA ƒ B (Volts)
i(V) (T)
e = 2πx[36] x[0.0139] x ƒ B (Volts)
i(V) (T)
e = [3.144] x ƒ B (Volts)
i(V) (T)
substituting known constants (number of turns and coil area)...
converting Volt/Tesla units to more convenient μV/pT units...
e
i(μV) (pT)
= 10 x[3.144] x ƒ B ( μV )
-6
ƒ
= frequency (in Hz)
where:
= open-circuit loop terminal voltage (in microvolts)
ei(μV)
= magnetic flux density (in picotesla)
B(pT)
EQUATION (3)
A
ƒ
N
= number of turns in loop coil = 36 turns
= area of coil = 0.0139 meters
= frequency
(in Hz)
= magnetic flux density (in Tesla)
2
= π r , where r = coil radius = 0.0665 meters
2
where:
= open-circuit loop terminal voltage (in Volts)
e
i(V)
B
(T)
e = 2πNA ƒ B (Volts)
i(V) (T)

Page 14 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 5 - ANTENNA THEORY
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
EXAMPLE CALCULATION #3
In the following example, Equation (4) is solved for the magnetic flux density (B)
assuming a frequency (ƒ) of 500 Hz, with the AL-RE101 Loop Antenna connected
to a high impedance oscilloscope input. The measured amplitude (ei)is 120 μV,
or 41.6 dBμV.
NOTE: The same result can be determined
using Equation (1) and the 100 kΩ antenna
conversion factor given in Figure 4.
EQUATION (1)
Magnetic
Field Strength
(in dBpT)
=
Measured
Value
(in dBμV)
Antenna
Conversion
Factor
(in dBpT/μV)
+
97.7 dBpT
=
[41.6]
dBμV
[56.1]
dBpT/μV
+
ei(μV) (pT)
= 10 x [3.144] x ƒ B (μV)
-6
as voltage is the known quantity, the formula is rearranged to solve for flux density...
=(pT)
x[3.144] x ƒ
10
-6
e
i(μV)
B(pT)
(pT)
x[3.144] x[500]
10
-6
[120]
=
B(pT)
= 76,336 pT
B(pT)
= 97.7 dBpT (20*log[pT])
B(pT)
substituting known variables (voltage and frequency)...
converting linear result into logarithmic units...

Page 15 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 5 - ANTENNA THEORY
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
5.2 Determination of Antenna Conversion Factors
The basic formulae for determining the antenna conversion factors for the
antenna are given in Equation (5) and Equation (6). Considered in these
equations are the frequency and resistance, inductance, area and number of
turns of the loop coil:
The derivation of Equation (6) is given in section 5.1.1.
In the formulae below, Equation (6) is reformulated to integrate the actual
resistance (RC), inductance (L), number of turns (N) and coil area (A) for the AL-
RE101 Loop Antenna; in Equation (7):
where:
RL
= load resistance [or input impedance of measurement instrument] (in ohms)
RC
= loop coil resistance = 10Ω
L
= loop coil inductance = 0.00034 H
VL(μV)
= voltage across R (in μV)
L
ƒ
N
= number of turns in loop coil = 36 turns
= frequency
(in Hz)
A
= area of coil = 0.0139 meters2
= π r , where r= coil radius = 0.0665 meters
2
(pT)
B
= magnetic flux density (in pT)
= antenna conversion factor (in pT/μV)
ACF
EQUATION (5)
EQUATION (6)
ACF = 20Log (dBpT/μV)
VL(μV)
(pT)
B
( )
=[pT/μV]
V
L(μV)
B
(pT)
10
6
2π ƒ AN
R
C
R
L
1 +
( )
2
R
L
+
( )
2
2π ƒ L
EQUATION (7)
rearranging equation (6) to separate 2πLfrom ƒ ...
2π ƒ AN
(pT/μV)
=106
R
C
R
L
1 +
( )
2
+ (2πL)
( )
2
R
L
ƒ
2
V
L(μV)
(pT)
B
substituting known constants (coil resistance (R ), coil inductance (L),
number of turns (N) and coil area (A))...
C
equation (7) is determined...
2πx ƒ x [0.0139] x [36]
(pT/μV)
=106
[10]
R
L
1 +
( )
2
+ (2πx[0.00034])
( )
2
R
L
ƒ
2
V
L(μV)
(pT)
B
ƒ x [3.144]
(pT/μV)
=106
[10]
R
L
1 +
( )
2
+[4.564x10 ]
( )
2
R
L
ƒ
-6
V
L(μV)
(pT)
B

Page 16 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 5 - ANTENNA THEORY
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
EXAMPLE CALCULATION #4:
In the following example, the antenna conversion factor (ACF) is calculated using
Equation (5) and Equation (7). For the purposes of this example, the frequency
(ƒ) is assumed to be 500 Hz, and the measuring instrument termination or load
resistance (RL)is 50 ohms:
EXAMPLE CALCULATION #5:
In this example, Equation (7) is solved for magnetic flux density (B(pT))assuming a
frequency (
ƒ) of 500 Hz, with the AL-RE101 Loop Antenna connected directly to a
spectrum analyzer having an input impedance (RL)of 50 ohms, which indicates a
measured amplitude (VL(μV))of 100 μV, or 40 dBμV:
[500] x [3.144]
(pT/μV)
106
1 +
( )
2
+[4.564x10 ]
( )
2
-6
[10]
[50]
[500]
[50]
=
[763.5]
=(pT/μV)
ACF = 20Log (dBpT/μV)
ACF = 20Log([763.5]
) (dBpT/μV)
ACF = 57.7 dBpT/μV
V
L(μV)
(pT)
B
V
L(μV)
(pT)
B
V
L(μV)
(pT)
B
( )
[500] x [3.144]
(pT/μV)
10
6
1 +
( )
2
+[4.564x10 ]
( )
2
-6
[10]
[50]
[500]
[50]
=
[100]
[763.5]
=
[100]
(pT/μV)
[100] x [763.5]=(pT)
97.7 dBpT (20log[pT])=
76,350 pT=
(pT)
B
(pT)
B
(pT)
B
(pT)
B
(pT)
B
NOTE: For this example, the same result
can be determined using Equation (1) and
the 50Ω antenna conversion factor given in
Figure 4.
EQUATION (1)
Magnetic
Field Strength
(in dBpT)
=
Measured
Value
(in dBμV)
Antenna
Conversion
Factor
(in dBpT/μV)
+
97.7 dBpT
=
[40.0]
dBμV
[57.7]
dBpT/μV
+

Page 17 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 5 - ANTENNA THEORY
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
5.2.1 Derivation of Antenna Conversion Factor Equation
The formulae below demonstrates the derivation of Equation (6) for
determination of the loop antenna conversion factors (ACF).
Equation (6a) was introduced earlier as Equation (3). It is borrowed from
basic magnetic loop theory, and establishes the relationship between the
physical parameters of the loop antenna, the magnetic flux density
present within the loop coil, and the open circuit voltage developed
across the loop terminals.
During actual measurements, the antenna terminals are terminated by
the input impedance of the measuring instrument (RL).The measured
voltage (VL)is proportional to the impedance of the loop coil (RC) + (jXC)
and (RL). This relationship is demonstrated in Equation (6b), and then
rearranged in Equation (6c) and Equation (6d).
EQUATION (6a)
A
ƒ
N
= number of turns in loop coil = 36 turns
= area of coil = 0.0139 meters
= frequency (in Hz)
= magnetic flux density (in Tesla)
2
= π r , where r = coil radius = 0.0665 meters
2
where:
= open-circuit loop terminal voltage (in Volts)
e
i(V)
B
(T)
e = 2πNA ƒ B (Volts)
i(V) (T)
EQUATION (6b)
e
i(V)
+ R
C
+ jX
C
R
L
=V
L(V)
R
L
where:
ei(V)
RC
j XC
RL
= open-circuit loop terminal voltage (in Volts)
= load resistance
[or input impedance of measurement instrument] (in ohms)
= loop coil resistance
= 10Ω
= loop coil reactance (2π
ƒL) (in ohms)
L
= inductance of the loop coil = 0.00034 H
L
EQUATION (6c)
=
e
i(V)
V
L(V)
R
C
R
L
1 + X
C
R
L
+ j
=R
C
R
L
1 +
( )
2X
C
R
L
+
( )
2
e
i(V)
V
L(V)
EQUATION (6d)
VL(V) = voltage across R (in Volts)
L

Page 18 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 5 - ANTENNA THEORY
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
In Equation (6e), Equation (6a) is integrated to substitute for (ei) in order to
solve for (|B/VL|)
And finally, in Equation (6f), we multiply by 106in order to convert the units
from Tesla/Volt into pT/V.
EQUATION (6f)
=[pT/μV]
V
L(μV)
B
(pT)
10
6
2π ƒ AN
R
C
R
L
1+
( )
2X
C
R
L
+
( )
2
EQUATION (6e)
=2π
ƒ AN (Tesla per Volt [T/V])
V
L(V)
B
(T)
R
C
R
L
1+
( )
2X
C
R
L
+
( )
2

Page 19 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 6 - CALIBRATION
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
6.0 Calibration and Calibration Cycle
Your AL-RE101 Loop Antenna has been individually calibrated with NIST traceability, and
the appropriate data and certificate has been provided. Periodic re-calibration of the
AL-RE101 is recommended. Calibration intervals is left to your discretion, but should be
chosen based on the frequency with which it is used, and/or as allowed for by your
internal quality control system (if applicable). Com-Power offers NIST traceable
calibration services. Recognized ISO 17025 accredited calibrations are also available.
6.1 Calibration Equipment
During calibration, the current flowing through the transmitting loop must be
monitored. The current can be monitored by measuring the voltage drop across
a 1 ohm resistor placed in series with the drive line to the transmit loop; or it can
be monitored using a current probe placed around the drive line to the transmit
loop.
Typical measurement setups for the respective calibration methods are illustrated
in Figure 5 and Figure 6.
FIGURE 5 - Typical Measurement Setup for Calibration (1ΩResistor Method)
FIGURE 6 - Typical Measurement Setup for Calibration (Current Probe Method)
AL-RS101-TX
Loop Antenna
(Transmitting)
AL-RE101
Loop Antenna
(Receiving)
12
cm
loops must
be parallel
and aligned
coaxially
Source
Equipment
Measuring
Instrument #2
50Ω
INPUT
Measuring
Instrument #1
CLCE-400
RFCURRENT PROBE
10kHz to 400 MHz
www.com-power.com
50Ω
INPUT
AL-RS101-TX
Loop Antenna
(Transmitting)
AL-RE101
Loop Antenna
(Receiving)
12
cm
loops must
be parallel
and aligned
coaxially
1Ω
PRECISION SERIES
RESISTOR (10 Watt)
Measuring
Instrument #2
50Ω
INPUT
HIGH Z
INPUT
Source
Equipment
Measuring
Instrument #1
(Powered
through
isolation
transformer)

Page 20 of 26
INSTRUCTION MANUAL
AL-RE101 LOOP ANTENNA

SECTION 6 - CALIBRATION
19121 El Toro Rd ●Silverado, California 92676 ●[phone] ●com-power.com
Rev101617
6.1.1 Source Equipment
The following subsections describe the type of equipment that will be
needed in order to perform calibration of the AL-RE101 Loop Antenna.
As current flowing through the transmitting loop antenna is monitored
during the calibration, the type of source equipment has no real
restriction; only that it be able to supply the desired current.
It is desirable from an efficiency standpoint that the output impedance of
the source be as low as possible. The greater the output impedance of
the source, the greater the power required to generate the same current.
Some typical examples of signal sources are given below.
•Signal (or function) generator with a power amplifier, such as the
Com-Power ARI-300K Audio Power Amplifier.
•Signal (or function) generator with power amplifier and output
transformer.
•Signal (or function) generator with transformer
•Signal (or function) generator with current amplifier
•Power sweep generator
•Network analyzer
•Spectrum Analyzer with tracking generator
6.1.2 Measuring Instruments
Any properly functioning, calibrated measuring instrument, or
combination of measuring instruments, having the proper input
impedance and operational specifications/capabilities for the
measurement functions for which it will be employed may be used for the
calibration. Typical types of instruments include oscilloscopes, spectrum
analyzers, EMI receivers, true rms volt meters, digital multimeters, etc.
6.1.3 Transmitting Loop Antenna
The Com-Power AL-RS101-TX Loop Antenna is the ideal antenna to use as
the transmitting loop during the calibration. Other transmitting loops may
also be used; however, the calibration-related calculations provided in
section 6.2 apply only to calibrations performed using the AL-RS101-TX
Loop Antenna.
6.1.4 Precision 1-ohm Series Resistor
This is a standard accessory provided with the Com-Power RS-101-TX Loop
Antenna. The resistor must be a precision, 1% tolerance resistor with
sufficient power rating.
6.1.5 RF Current Probe
Any properly functioning, calibrated current probe having appropriate
operational specifications/capabilities for the measurement functions for
which it will be employed may be used for the calibration.