5130 Power Meter Operating & Service Manual
AZD Technology LLC ~ Albuquerque, NM 87112
www.azdtechnology.com
Copyright © AZD Technology L.L.C. All rights reserved.
TABLE OF CONTENTS
Section Title Page
SECTION 1, GENERAL INFORMATION.................................................................................................................................. 2
1.1 Introduction............................................................................................................................................................ 2
1.3 SPECIFICATIONS.......................................................................................................................................................... 2
SECTION 2, INSTALLATION..................................................................................................................................................... 2
2.1 Introduction............................................................................................................................................................ 2
2.3 Initial Inspection................................................................................................................................................... 2
2.5 AC Power Requirements.................................................................................................................................... 3
2.7 AC Power Cable....................................................................................................................................................... 3
2.9 Temperature.............................................................................................................................................................. 3
SECTION 3, OPERATION............................................................................................................................................................ 3
3.1 Introduction............................................................................................................................................................ 3
3.3 CW Power Measurement.................................................................................................................................... 3
3.11 Amplitude Modulated Power........................................................................................................................ 6
Section 4, Performance Tests....................................................................................................................................... 8
4.1 Introduction............................................................................................................................................................ 8
4.3 Test Equipment......................................................................................................................................................... 8
4.8 CW Input Power....................................................................................................................................................... 9
4.11 Rear Panel BNC Connector DC Output Levels................................................................................... 9
Section 5, Service................................................................................................................................................................... 9
5.1 Introduction............................................................................................................................................................ 9
5.5 Theory of Operation......................................................................................................................................... 11
5.7 9520 Sensor............................................................................................................................................................... 11
5.15 Test Points............................................................................................................................................................... 12
5.17 Test Conditions.................................................................................................................................................... 14
5.18 Power Supply Measurements, Test Condition 1.............................................................................. 14
5.19 Differential Input Measurements, Test Condition 1.................................................................... 14
5.20 U1B Output, Test Point A.................................................................................................................................. 14
Section 6, Replacement Parts..................................................................................................................................... 17
6.1 Introduction.......................................................................................................................................................... 17
6.3 Printed Circuit Board Assemblies.......................................................................................................... 18
6.4 Cabinet Components & Hardware........................................................................................................... 18
Section 7, Calibration..................................................................................................................................................... 18
7.1 Introduction.......................................................................................................................................................... 18
7.3 First Method Calibration............................................................................................................................. 18
7.17 Second Method Calibration....................................................................................................................... 22
7.31 End of Document.................................................................................................................................................. 25
SECTION 1, GENERAL INFORMATION
1.2 This manual provides information about the installation, operation, testing, and maintenance of the AZD Technology 5130 Power Meter.
Input
The following input specifications apply to the AZD 9520 Sensor only.
Frequency Range: 0.01 to 1.8 GHz
Power Range: -27 dBm (2 uW) to -3 dBm (0.5 mW).
Input Coupling: AC
Input Return Loss: greater than 20 dB (less than 1.1 SWR), 0.01 to 1.8 GHz (50 ohms nominal)
Damage Level: 1 watt CW
Maximum amplitude modulation: 82 % from 0.01 to 1.8 GHz
Output
Front panel digital display: -199.9 to +199.9 dBm. Rear panel Connector: BNC–F, -1.999 to +1.999 VDC, for connection to a DVM for data logging or an oscilloscope for viewing the swept measurement response of a two port device. Application of the10X probe function on the oscilloscope or the math function on the DVM is required to remove the scaling factor and make the oscilloscope or DVM agree with the 5130 front panel display.
General
Operating Temperature Range: 65 to 85 degrees C
Power Requirements: 105V to 125 VAC, 60 Hz AC, 5 Watts nominal, 7 Watts maximum.
Overall Dimensions: 8.125 wide X 7.0 deep X 3.875 high (inches)
Weight: 2.5 Pounds
2.2 This section provides information necessary to install the 5130 Power Meter. Initial inspection, AC power requirements, and ambient temperature are covered in this section.
2.4 Inspect the cardboard box for damage. If the cardboard box or foam plastic is damaged, it should be kept until the 5130 Power Meter has been checked for mechanical and electrical damage. Notify AZD Technology if the box contents are not complete, if there is mechanical defect, or if the 5130 Power Meter does not pass the electrical performance tests. Notify the carrier, if the shipping container or foam plastic is damaged. Keep the shipping material for the carrier’s inspection.
2.8 The 5130 Power Meter is shipped with a standard three-wire AC power cable permanently attached.
2.10 To maintain accuracy, the ambient temperature of the area in which the 5130 Power Meter is being used must be between 65 to 85 degrees F.
3.2
This section provides the information necessary to
setup the 5130 Power Meter for CW power measurements.
Figure 1, 5130 Power Meter Front Panel
3.4 Before connecting the Power Sensor cable, make sure the 5130 Power Meter AC power switch is in the OFF position and the power cord is unplugged from the AC outlet.
3.5 The Power Sensor cable connector is a bayonet locking type that is keyed so cable connector key alignment with the panel connector notch is required when inserting. The square hole in the cable connector plastic barrel should to be positioned at about +80 degrees to allow insertion and locked by rotating the barrel clock-wise about 10 degrees. After the sensor is plugged into the 5130 front panel sensor connector, plug the power cable into a standard 115 VAC, 60 Hz power outlet and set the AC switch lever to the ON position. Make sure the output of the VHF/UHF source to be tested is off, and connect the 9520 Sensor to the source output. If the VHF/UHF source output level is above –3 dBm, an attenuator is required between the 9520 sensor and source output. After the 5130 and 9520 are allowed to temperature stabilize for about 15 minutes, change the zero-set switch lever to the up position and adjust the front panel zero-set control knob so the display reads 000.0. After coarse zeroing return the zero-set switch lever to the down position, and with the zero-set control knob, adjust the 5130 display to a reading between -40 and -170 dBm (fine zero). After stabilization and the two-step zeroing process, the output of the VHF/UHF source can be turned on for a power measurement.
3.6 Figure 2 shows typical measurement accuracy for a -9 dBm sensor input power at frequencies from 100 to 1800 MHz.
Figure 2, Typical Accuracy @ -9 dBm Sensor Input Power
3.7 Figure 3 shows the 5130 accuracy when measuring a CW source set to 900 MHz and levels from -27 to +0 dBm.
Figure 3, 5130 Typical Accuracy @ 900 MHz
3.8 If the VHF/UHF source level is above -3 dBm, insert a coaxial attenuator between the 9520 sensor and the VHF/UHF power source. The attenuator value in dB will need to be added to the 5130 display reading. For example, if the 5130 display shows -3 dBm and a 20 dB attenuator is connected between the source and sensor, the actual source power is 17 dBm.
3.9 To take advantage of the mid-range accuracy of the 9520/5130, connect an attenuator between the VHF/UHF source and 9520 Sensor that produces a display reading between -24 and -6 dBm.
3.10 The following is an explanation of how power dissipation of the attenuator connected to the 9520 Sensor effects zero drift. If a 30 dB attenuator is used and the 5130 displays -4 dBm, the attenuator input power is 26 dBm (0.4 watt). At this power level, the body of a 0.5-watt SMA attenuator will rise in temperature and heat the 9520 sensor SMA connector. Because of heat conduction through the SMA connector and copper micro-strip line on the sensor substrate, the detector and reference diodes are at slightly different temperatures and zero drift will occur. If power measurements are performed that require attenuation above 20 dB, changing to a directional coupler is the best option (see Figure 4) that will avoid sensor heating and minimize zero drift. With a directional coupler, a small amount of the incident power is diverted to the coupled port and most of the power is transferred to the load. For a 30 dB coupler, 0.1 percent is diverted to the coupled port and 99.9 percent flows to the load. Adding a 30 dB, 0.5-watt attenuator to the coupled port will raise the maximum input power limit to 57 dBm (500 watts).
Figure 4, Power Measurement Above 26 dBm
3.11 Amplitude Modulated Power
3.12 Figure 5 shows an oscilloscope waveform of a 100 MHz carrier modulated by a 1 KHz tone, and Figure 6 shows the resulting output at the 5130 rear panel BNC connector. The peak level (Cursor 2) 292 mV divided by the valley level (Cursor 1) is a voltage ratio of 3.174 or a power ratio of 10.074 (10.032 db). Figure 6, an oscilloscope waveform measurement of the output of the 5130 rear panel BNC connector shows the peak - peak amplitude to be 10.2 volts. Since the calibration at this point is 1 volt/dB, the peak - peak amplitude in dB is 10.2.
3.13 To keep the 9520 Sensor in the square law range, the power at the peak of the waveform should not exceed -3 dBm, and the power at the valley of the waveform should not be less than -24 dBm. These limits produce a power range of 21 dB or a voltage range of 11.22. When E max is 11.22E min, a modulation index of 83 % is produced. Above this index, the power measurement error will increase. Figure 7 shows the result of attenuating the sensor input power level so that clipping occurs and the peak – peak swing (Delta) becomes 6.72 dB.
Figure 5, Amplitude Modulated Sensor Input Power
Figure 6, 5130 Rear Panel BNC Connector Output
Figure 7, 5130 Rear Panel BNC Connector Output
4.2 Performance evaluation of the 5130 Power Meter is accomplished by comparing measured data created with the test equipment specified in paragraphs 4.5 through 4.7 against the data of paragraphs 4.10 through 4.13.
4.4 The test equipment required for performance evaluation of the 5130 Power Meter is given in paragraph 4.5 through 4.7.
4.5 RF Signal Generator Requirements
|
Frequency Range (MHz) |
Power Range (dBm) |
Modulation Index |
Modulation Frequency |
|
|
10 to 1800 |
-27.0 to 0.0 |
0 to 90 % |
1.0 KHz |
|
4.6 RF Signal Generator Accuracy Requirements
|
Frequency Range (MHz) |
Power Range (dBm) |
Accuracy (MHz) |
Accuracy (dBm) |
|
|
10 to 1800 |
-27 to 0.0 |
+/- 1 |
+/- 0.1 |
|
4.7 Oscilloscope Requirements
|
Bandwidth |
Vertical Input |
Trigger Input |
|
|
|
100 MHz |
|
|
|
|
4.9
The table of paragraph 4.10 gives CW power and
frequency requirements for the evaluation of the measurement capabilities of
the 5130/9520.
4.10 CW Source Power and Frequency Requirements
|
Frequency (MHz) |
Minimum Power Level (uW) |
Minimum Power Level (dBm) |
Maximum Power Level (mW) |
Maxium Power Level (dBm) |
|
10 to 1800 |
2.0 |
-27 |
0.5 |
-3.0 |
4.11 Rear Panel BNC Connector DC Output Levels
4.12 The table of paragraph 4.13 gives rear panel BNC connector output voltage levels and upper/lower limits as a function of the 9520 Sensor response to CW input power and the processing of the analog computer board. This BNC output is used for connection to a DVM for data logging or an Oscilloscope for viewing the swept measurement response of a two port device. Application of the10X function on the oscilloscope or the math function on the DVM is required to remove the scaling factor and make the BNC connector output agree with the front panel display.
4.13 5130 Power Meter Rear Panel BNC Connector Output Levels
|
9520 Input (dBm) |
Nominal Output Level (VDC) |
Minimum Output Level (VDC) |
Maximum Output Level (VCD) |
|
-27.0 |
-2.7 |
-2.66 |
-2.74 |
|
-24.0 |
-2.4 |
-2.38 |
-2.42 |
|
-21.0 |
-2.1 |
- 2.08 |
- 2.12 |
|
-18.0 |
-1.8 |
- 1.78 |
- 1.82 |
|
-12.0 |
-1.2 |
- 1.18 |
- 1.22 |
|
-9.0 |
-0.9 |
-0.88 |
-0.92 |
|
-6.0 |
-0.6 |
-0.58 |
-0.67 |
|
-3.0 |
-0.3 |
-0.26 |
-0.34 |
WARNING
LINE VOLTAGE IS EXPOSED WITHIN THE 5130 POWER METER EVEN WHEN THE POWER SWITCH IS IN THE OFF POSITION. UNPLUG THE 5130 POWER CORD FROM THE AC POWER OUTLET TO FULLY UNPOWER THE INSTRUMENT.
5.2 This section contains information needed to service the 5130 Power Meter.
Figure 12, 5130 Power Meter Back Panel
5.3 Before removing the fuse, turn off and unplug the unit. To remove the fuse from the fuse holder, push in and twist the fuse holder cap section counter-clockwise approximately 45 degrees and pull straight back. The fuse is held in the fuse holder cap section by a spring contact and should be pulled out of the cap section for inspection.
5.4 Turn off the unit and unplug the AC power cord. Remove the six 6-32 machine screws (one on each side, two front and back edges) that hold the cabinet top to the base and pull the top straight up and off to gain access to the circuit assemblies and components.
Figure 13, 5130 Power Meter inside View
5.6 The theory of operation is organized in such a way that a block diagram is referred to during the explanation of each major component. Figures 16 and 17 are circuit diagrams of the logarithmic amplifier and panel meter interface assemblies and are included to clarify circuit operation.
Figure 14, 5130 POWER METER BLOCK DIAGRAM
5.8 A VHF/UHF signal applied to the 9520 Sensor connector is first attenuated by 16 dB to keep the Schottky Barrier detector diode operating in the Square-Law region with power levels up to -3 dBm.
5.9 The detector diode is biased at approximately 27 uA to lower its video resistance to a point where it can drive a DC load. To remove the DC component caused by the DC bias and provide temperature compensation, an additional diode of the same type as the detector is included on the sensor substrate. With the same bias and proximity, the DC levels on the detector and reference diodes are approximately equal.
5.10 The output of both diodes, detector and reference, are connected through a shielded cable to a low drift, low offset differential amplifier of Figure 14. With no VHF/UHF power applied to the 9520 Sensor, the differential amplifier output is zero except for an offset of less than 10 mV which can be zeroed out with the 5130 front panel zero control.
5.11 When a VHF/UHF signal is connected to the 9520 Sensor input connector, the DC level on the detector diode changes and differential amplifier # 1 produces an amplified level which drives the input of a logarithmic amplifier through two inverter stages. Differential amplifier # 2 compares the output of the log amp to a temperature compensated reference voltage and produces a DC level representing the 9520 Sensor input power in dBm. The output scale at this point is 0.1 volt/dBm and is available at the rear panel BNC connector for viewing the swept response of a two port device on an oscilloscope or data logging with a DVM equipped with a RS-232 port.
5.12 The output of differential amplifier # 2 also supplies a 0.1 volt/dBm level to the Digital Panel Meter Interface PC Board assembly and the result is displayed as 1 volt/dBm because of decimal point selection. With –19.99 to +19.99 input to the interface board, the Panel Meter displays -199.9 to +199.9 dBm
5.13 Power Supply
5.14
Two DC power sources are required to power the circuits
of the 5130 Power Meter. Both the +18 volt and -18 volt regulators are
located on the Analog Computer printed circuit board assembly. The center
tapped secondary of the power transformer allows the +18 volt regulator to be
supplied from the filtered and unregulated DC from the positive side of the
bridge rectifier, and the -18 volt regulator is supplied by the filtered and
unregulated DC from the negative side of the bridge rectifier. The Analog
Computer circuits use +18 and -18 volts and the Panel Meter interface PC Board
Assembly has additional regulators to produce +5 volts and -5 volts required
by the Digital Panel Meter.
5.16 The following voltages are present at the designated test points for each of the four test conditions of paragraph 5.17. The voltages of paragraphs 5.18 through 5.20 are measured on the Analog Computer printed circuit assembly. The voltages of paragraphs 5.21 through 5.25 are measured on the panel meter interface printed circuit assembly. Refer to Figure 15 through 18 for the location of each test point.
Figure 15, Analog Computer Printed Circuit Board Assembly
Figure 16, Analog Computer Circuit Diagram
|
Test Condition |
RF Generator level (dBm) |
Generator Frequency MHz |
Modulation Index % |
Modulation Frequency KHz |
|
*1 |
-- |
-- |
-- |
-- |
|
2 |
-18.00 |
900 |
0 |
-- |
|
3 |
-12.00 |
900 |
0 |
-- |
|
4 |
-06.00 |
900 |
0 |
-- |
* 9520 Sensor SMA Connector terminated with a 50 ohm SMA load
5.18 Power Supply Measurements, Test Condition 1
|
Test Point |
Nominal |
Minimum |
Maximum |
Unit |
|
A1 |
21.194 |
19.830 |
22.559 |
VAC (RMS) |
|
A2 |
21.196 |
19.831 |
22.560 |
VAC (RMS) |
|
VR1 Input |
27.234 |
24.828 |
29.640 |
VDC |
|
VR2 Input |
-27.187 |
-25.988 |
-28.385 |
VDC |
5.19 Differential Input Measurements, Test Condition 1
|
Test Point |
Nominal |
Minimum |
Maximum |
|
H |
-0.211 |
-0.210 |
-0.212 |
|
L |
-0.211 |
-0.210 |
-0.212 |
5.20 U1B Output, Test Point A
|
Test Condition |
Nominal |
Minimum |
Maximum |
|
1 |
-0.0001 |
-0.0002 |
+0.0002 |
|
2 |
-0.0070 |
-0.0069 |
-0.0072 |
|
3 |
-0.0270 |
-0.0260 |
-0.0280 |
|
4 |
-0.0960 |
-0.0930 |
-0.1000 |
Figure 17, Panel Meter Interface Printed Circuit Assembly Component Side
Figure 18, Panel Meter Interface Circuit Diagram
5.21 Panel Meter interface Board, Test Point White
|
Test Condition |
Nominal VDC |
Minimum VDC |
Maximum VDC |
|
1 |
-4.30 |
-4.00 |
-5.00 |
|
2 |
-1.80 |
-1.78 |
-1.82 |
|
3 |
-1.20 |
-1.18 |
-1.22 |
|
4 |
-0.60 |
-0.58 |
-0.67 |
5.22 Panel Meter Interface Board, Test Point Grey
|
Test Condition |
Nominal VDC |
Minimum VDC |
Maximum VDC |
|
1 |
-0.0001 |
-0.0002 |
+0.0002 |
|
2 |
-0.0070 |
-0.0067 |
-0.0073 |
|
3 |
-0.0270 |
-0.0260 |
-0.0280 |
|
4 |
-0.0960 |
-0.0930 |
-0.1000 |
5.23 Panel Meter Interface Board, Test Point Yellow
|
Test Condition |
Nominal |
Minimum |
Maximum |
|
all |
-18.0 |
-17.9 |
-18.1 |
5.24 Panel Meter Interface Board, Test Point Green
|
Test Condition |
Nominal |
Minimum |
Maximum |
|
all |
18.0 |
17.9 |
18.1 |
5.25 Panel Meter Interface Board, Test Point P5
|
Test Condition |
Nominal |
Minimum |
Maximum |
|
all |
5.0 |
4.9 |
5.1 |
5.26 Panel Meter Interface Board, Test Point N5
|
Test Condition |
Nominal |
Minimum |
Maximum |
|
all |
-5.0 |
-4.9 |
-5.1 |
6.2 Replacement Parts are available through the AZD Technology web site www.azdtechnology.com
Figure 19, 5130 Wiring Diagram
6.3 Printed Circuit Board Assemblies
|
Description |
Part Number |
Quantity |
|
Analog Computer PCA |
PSLA01R0A |
1 each |
|
PM INTERFACE PCA |
V6CR1A |
1 each |
6.4 Cabinet Components & Hardware
|
Reference |
Description |
Part Number |
Quantity |
|
F1 |
fuse, 1/4 Amp 3AG SB |
313.250 |
1 each |
|
T1 |
power transformer, 36VCT/.3A |
P-8612 |
1 each |
|
|
fuse holder |
3453-LF1 |
1 each |
|
|
AC power cord |
17534 |
1 each |
|
|
relief bushing |
939 |
1 each |
|
|
terminal strip |
809 |
1 each |
|
|
rubber foot |
2135 |
4 each |
|
|
spacer |
2203 |
10 each |
|
|
cabinet |
CAB5130 |
1 each |
|
S1, 2 |
switch, SPDT |
7101 |
2 each |
|
J1 |
panel connector |
T 3377 |
1 each |
|
J2 |
BNC-F connector |
31-2221 |
1 each |
