National Instruments PXI-5661 User manual

GETTING STARTED GUIDE
NI PXI-5661
2.7 GHz RF Vector Signal Analyzer with Digital Downconversion
Note Before you begin, install and configure your chassis and controller.
This document explains how to install, configure, and test the NI PXI-5661 (NI 5661). The
NI 5661 is a modular 2.7 GHz RF vector signal analyzer (VSA) with wide real-time
bandwidth and digital downconversion. The NI 5661 ships with the NI-RFSA instrument
driver, which you use to program the device.
The NI 5661 comprises the following devices:
• NI PXI-5600 (NI 5600) RF downconverter module
• NI PXI-5142 (NI 5142) IF digitizer module
Caution The protection provided by this product may be impaired if it is used in a
manner not described in this document.
Hot Surface If the NI 5661 has been in use, it may exceed safe handling
temperatures and cause burns. Allow the NI 5661 to cool before removing it from
the chassis.
Contents
Electromagnetic Compatibility Guidelines...............................................................................2
Verifying the System Requirements......................................................................................... 2
Unpacking the Kit.....................................................................................................................2
Verifying the Kit Contents................................................................................................ 3
Preparing the Environment....................................................................................................... 4
Installing the Software.............................................................................................................. 4
Installing the NI 5661............................................................................................................... 5
Interconnecting the NI 5661 Modules.............................................................................. 6
Configuring the NI 5661 in MAX.......................................................................................... 14
Programming the NI 5661...................................................................................................... 16
NI-RFSA Examples........................................................................................................ 17
Troubleshooting...................................................................................................................... 18
Installation...................................................................................................................... 18
Configuration.................................................................................................................. 20
Measurements................................................................................................................. 21
Where to Go Next................................................................................................................... 22
Worldwide Support and Services............................................................................................22

Electromagnetic Compatibility Guidelines
This product was tested and complies with the regulatory requirements and limits for
electromagnetic compatibility (EMC) stated in the product specifications. These requirements
and limits are designed to provide reasonable protection against harmful interference when the
product is operated in the intended operational electromagnetic environment.
This product is intended for use in industrial locations. However, harmful interference may
occur in some installations, when the product is connected to a peripheral device or test object,
or if the product is used in residential or commercial areas. To minimize interference with
radio and television reception and prevent unacceptable performance degradation, install and
use this product in strict accordance with the instructions in the product documentation.
Furthermore, any modifications to the product not expressly approved by National Instruments
could void your authority to operate it under your local regulatory rules.
Caution To ensure the specified EMC performance, operate this product only with
shielded cables and accessories.
Caution To ensure the specified EMC performance, the length of all I/O cables
must be no longer than 3 m (10 ft).
Verifying the System Requirements
To use the NI-RFSA instrument driver, your system must meet certain requirements.
For more information about minimum system requirements, recommended system, and
supported application development environments (ADEs), refer to the product readme, which
is available on the driver software media or online at ni.com/updates.
Unpacking the Kit
Caution To prevent electrostatic discharge (ESD) from damaging the device,
ground yourself using a grounding strap or by holding a grounded object, such as
your computer chassis.
1. Touch the antistatic package to a metal part of the computer chassis.
2. Remove the device from the package and inspect the device for loose components or any
other sign of damage.
Caution Never touch the exposed pins of connectors.
Notify NI if the device appears damaged in any way. Do not install a damaged device.
3. Unpack any other items and documentation from the kit.
Store the device in the antistatic package when the device is not in use.
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Verifying the Kit Contents
Figure 1. NI 5661 Kit Contents
34
5
2
7
6
1
POWER
8
9 10 11
1. NI 5600 RF Downconverter Module
2. NI 5142 IF Digitizer Module
3. Semi-Flexible SMA-to-BNC Cable, Part Number
192975B-01
4. Semi-Flexible SMA-to-SMB Cable, Part Number
192973B-01
5. Semi-Flexible SMA-to-SMA Cable, Part Number
150611A-01
6. Cable Wrench (x2)
7. Screwdriver, Part Number 772006-01
8. Driver Software DVD
9. Read Me First: Safety and Electromagnetic
Compatibility
10. Maintain Forced-Air Cooling Note to Users
11. NI PXI-5661 Getting Started Guide (This
Document)
NI PXI-5661 Getting Started Guide | © National Instruments | 3

Other Equipment
There are several required items not included in your device kit that you need to install or
operate the NI 5661.
Required Items
• A PXI chassis and chassis documentation. The NI PXI-1045 chassis is one available
option for your device. For more information about compatible chassis options, refer to
ni.com.
• A PXI embedded controller or MXI controller system that meets the system requirements
specified in this guide and chassis documentation.
Optional Items
• A 1 N · m standard SMA torque wrench (NI part number 780487-01).
Preparing the Environment
Ensure that the environment you are using the NI 5661 in meets the following specifications.
............................................................................Operating ambient temperature
(IEC-60068-2-1, IEC-60068-2-2)
0 °C to 50 °C
............................................................................Operating relative humidity
(IEC-60068-2-56)
10% to 90%, noncondensing
............................................................................Maximum altitude 2,000 m (800 mbar) (at 25 °C ambient
temperature)
............................................................................Pollution Degree 2
Indoor use only.
Caution Clean the hardware with a soft, nonmetallic brush. Make sure that the
hardware is completely dry and free from contaminants before returning it to
service.
Note Refer to the NI PXI-5661 Specifications at ni.com/manuals for complete
specifications.
Installing the Software
You must be an Administrator to install NI software on your computer.
1. Install an ADE, such as LabVIEW or LabWindows™/CVI™.
2. Insert the driver software media into your computer. The installer should open
automatically.
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If the installation window does not appear, navigate to the drive, double-click it, and
double-click autorun.exe.
3. Follow the instructions in the installation prompts.
Note Windows users may see access and security messages during
installation. Accept the prompts to complete the installation.
4. When the installer completes, select Restart in the dialog box that prompts you to restart,
shut down, or restart later.
Installing the NI 5661
Caution To prevent damage to the device caused by ESD or contamination, handle
the device using the edges or the metal bracket.
1. Ensure the AC power source is connected to the chassis before installing the modules.
The AC power cord grounds the chassis and protects it from electrical damage while you
install the modules.
2. Power off the chassis.
3. Inspect the slot pins on the chassis backplane for any bends or damage prior to
installation. Do not install a module if the backplane is damaged.
4. Remove the black plastic connectors from all the captive screws on the module front
panel.
5. Identify a supported slot in the chassis. The following figure shows the symbols that
indicate the slot types.
Figure 2. Chassis Compatibility Symbols
NI PXIe-1062Q
12 3 45
1. PXI Express System Controller Slot
2. PXI Peripheral Slot
3. PXI Express Hybrid Peripheral Slot
4. PXI Express System Timing Slot
5. PXI Express Peripheral Slot
NI 5661 modules can be placed in PXI peripheral slots or PXI Express Hybrid peripheral
slots.
6. Touch any metal part of the chassis to discharge static electricity.
7. Ensure that the ejector handle is in the unlatched (downward) position.
8. Place the module edges into the module guides at the top and bottom of the chassis. Slide
the device into the slot until it is fully inserted.
NI PXI-5661 Getting Started Guide | © National Instruments | 5

Figure 3. Module Installation
2
3
NI PXIe-1075
1
1. Chassis
2. Hardware Module
3. Ejector Handle in Down (Unlatched) Position
9. Latch the module in place by pulling up on the ejector handle.
10. Secure the device front panel to the chassis using the front-panel mounting screws.
Note Tightening the top and bottom mounting screws increases mechanical
stability and also electrically connects the front panel to the chassis, which can
improve the signal quality and electromagnetic performance.
11. Cover all empty slots using filler panels or slot blockers to maximize cooling air flow.
12. Power on the chassis.
Related Information
Installing the Software on page 4
Interconnecting the NI 5661 Modules
Caution The signal pins of this product's input/output ports can be damaged if
subjected to ESD. To prevent damage, remove power from the product before
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connecting cables and employ industry-standard ESD prevention measures during
installation, maintenance, and operation.
Figure 4. NI 5661 Front Panel Interconnection
TRIG
CH 0
NI PXI-5142
ACCESS ACTIVE
CH 1
AUX I/O +5 V
MAX
CLK IN CLK OUT
100 MS/s OSP Digitizer
NI 5600
POWER
STATUS
RF DOWNCONVERTER
+20 dBm MAX
+30 dBm MAX
WITH ATTN
± 5 V DC MAX
PXI 10 MHz I/O
± 5 V DC MAX
+23 dBm MAX
3
2
1
1. Semi-Flexible SMA-to-BNC Cable
2. Semi-Flexible SMA-to-SMB Cable
3. (Optional) Semi-Flexible SMA-to-SMA Cable
1. Using the short semi-flexible SMA-to-BNC coaxial cable, connect the OUTPUT
connector on the NI 5600 front panel to the CH 0 connector on the NI 5142 front panel.
2. Using the long semi-flexible SMA-to-SMB coaxial cable, connect the lower of the two
10 MHz OUT connectors on the NI 5600 front panel to the CLK IN connector on the
NI 5142 front panel.
3. (Optional) Using the semi-flexible SMA-to-SMA coaxial cable center pin, connect the
bidirectional PXI 10 MHz I/O connector on the NI 5600 front panel to the other
10 MHz OUT connector on the NI 5600 front panel. This connection drives the
PXI 10 MHz backplane with the NI 5600 onboard frequency reference.
Note You can use this connection to drive the PXI 10 MHz backplane clock
only when the NI 5600 RF downconverter module is installed in Slot 2 of a
PXI chassis.
4. Hand-tighten all SMA cable ends on the SMA connectors after the cable center pins are
correctly aligned and connected. The cable connectors should tighten without much
torque or effort. If a cable bends due to incorrect alignment, remove the cable from the
NI PXI-5661 Getting Started Guide | © National Instruments | 7

front panel connector and reconnect the cable center pin on the SMA cable to the SMA
connector.
5. Carefully complete tightening all SMA connectors to 1 N · m using an appropriate torque
wrench (not included) or torque screwdriver and SMA driver bit. Tighten only until the
wrench clicks.
Caution Incorrect torque at SMA connections can degrade signal fidelity and
phase-locked loop (PLL) performance and may cause insertion loss. Use an
appropriate torque wrench or torque screwdriver and SMA driver bit to ensure
all SMA connections are properly torqued. SMA connectors for connections to
external equipment may require torque different from 1 N · m, depending on
the connector type, material, and manufacturer.
6. Power on the PXI chassis and controller system.
7. Verify that the POWER LED on the NI 5600 RF downconverter module is on.
Related Information
Troubleshooting on page 18
If an issue persists after you complete a troubleshooting procedure, contact NI technical
support or visit ni.com/support.
Direct Connections to the NI 5600
The NI 5600 is a precision RF instrument that is sensitive to ESD and transients. Ensure you
are making proper direct connections to the NI 5600 to avoid damaging the device.
Caution Apply external signals only while the NI 5600 is powered on. Applying
external signals while the device is powered off may cause damage.
• Ensure you are properly grounded when manipulating cables or antennas connected to the
NI 5600 INPUT connector.
• If you are using noninsulated devices, such as a noninsulated RF antenna, ensure the
devices are maintained in a static-free environment.
• If you are using an active device, such as a preamplifier or switch routed to the NI 5600
INPUT connector, ensure that there are no signal transients greater than the RF and DC
specifications for the device that are being generated and sourced to the NI 5600 INPUT
connector.
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NI 5600 RF Downconverter Module Front Panel
The NI 5600 RF downconverter module front panel contains six connectors and two LEDs.
Figure 5. NI 5600 RF Downconverter Module Front Panel
INPUT
50 Ω
0 V DC MAX
OUTPUT
50 Ω
5 MHz - 25 MHz
+20 dBm MAX
+30 dBm MAX
WITH ATTN
PXI 10 MHz I/O
50 Ω
+23 dBm MAX
± 5 V DC MAX
10 MHz OUT
1 V pp 50 Ω
FREQ. REF IN
50 Ω
+16 dBm MAX
±5 V DC MAX
NI 5600
POWER
STATUS
RF DOWNCONVERTER
Table 1. Device Front Panel Icon Definition
Refer to the user documentation for required maintenance measures to ensure user
safety and/or preserve the specified EMC performance.
NI PXI-5661 Getting Started Guide | © National Instruments | 9

Table 2. NI 5600 RF Downconverter Module Front Panel Connectors
Connector Use
FREQ REF IN Routes an external frequency reference signal to which the NI 5600
can lock. You can propagate this signal to the PXI backplane when
the NI 5600 is installed in PXI Slot 2.
10 MHz OUT
(two connectors)
Generates replications of the downconverter 10 MHz frequency
reference signal. These replicated signals are useful for driving other
devices. Each replication is 180° out of phase with the other. The
signal output at these connectors is always on and cannot be
disabled.
Connect the lower 10 MHz OUT connector to the REF CLK IN
connector on the NI 5620 module front panel or to the CLK IN
connector on the NI 5142.
PXI 10 MHz I/O Provides bidirectional connection to the PXI 10 MHz backplane
clock.
You can use this connector to drive the PXI 10 MHz backplane clock
only when the NI 5600 is installed in PXI Slot 2. You can use this
connector to export the PXI 10 MHz backplane clock when the
NI 5600 RF downconverter is installed in any PXI slot.
OUTPUT Connects to the INPUT connector on the NI 5142 IF digitizer
module front panel.
This connector is the output terminal for the frequency-translated IF
signal for digitization.
INPUT Connects to the analog RF input signal to be measured by the
NI 5661.
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Table 3. NI 5600 RF Downconverter Module Front Panel LEDs
LED Indications
POWER Indicates the basic hardware power status of the NI 5600 RF downconverter
module. This LED functions identically to the ACCESS LED on the NI 5142 IF
digitizer module front panel.
OFF—The module is not yet functional, or has detected a problem with a power
rail.
GREEN—The module is functional and receiving power.
STATUS Indicates the status of the NI 5600 RF downconverter module PLLs.
OFF—The module is in an uninitialized state, or the module PLLs are attempting
to lock.
GREEN—The module is in a ready state; applicable PLLs are locked.
Related Information
Refer to the NI RF Vector Signal Analyzers Help for more information about using the PXI 10
MHz I/O connector.
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NI 5142 IF Digitizer Module Front Panel
The front panel of the NI 5142 IF digitizer module contains six connectors and two LEDs.
Figure 6. NI 5142 IF Digitizer Module Front Panel
TRIG
CH 0
NI PXI-5142
ACCESS ACTIVE
CH 1
AUX I/O +5 V
MAX
CLK IN CLK OUT
100 MS/s OSP Digitizer
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Table 4. Device Front Panel Icon Definition
Refer to the user documentation for required maintenance measures to ensure user
safety and/or preserve the specified EMC performance.
Table 5. NI 5142 IF Digitizer Module Front Panel Connectors
Connector Use
CH 0 Connects to the OUTPUT connector on the NI 5600 front panel.
This connector is the input terminal for a frequency-translated IF waveform
from the NI 5600 RF downconverter for digitization and measurement.
CH 1 This input terminal is not used for NI 5661 operation. CH 0 is the only channel
with digital downconverter (DDC) capabilities.
TRIG This connector is the input terminal for a digital trigger from an external source.
CLK IN Connects to the lower 10 MHz OUT connector on the NI 5600 RF
downconverter module front panel.
This connector is the input terminal for the NI 5600 internal Reference Clock
signal.
CLK OUT This connector is the output terminal for the NI 5142 Reference Clock or
Sample Clock.
AUX I/O Provides access to the multipurpose digital timing and triggering lines, PFI 0,
and PFI 1 (with optional cable).
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Table 6. NI 5142 IF Digitizer Module Front Panel LEDs
LED Indications
ACCESS Indicates the basic hardware status of the NI 5142 module.
OFF—The module is not yet functional, or the module detected a problem with a
power rail.
AMBER—The module is being accessed. Accessed means that the device setup
registers are being written to in order to control the device.
GREEN—The module is ready to be programmed by NI-RFSA.
ACTIVE Indicates the NI 5142 module state.
OFF—The module is not armed, triggered, or acquiring a waveform.
AMBER—The module is armed and waiting for a trigger.
GREEN—The module has received a Reference Trigger. Also indicates that the
module is acquiring a waveform.
RED—The module has detected an error. The LED remains red until the error
condition is removed.
Related Information
Refer to the NI High-Speed Digitizers Help for more information about triggering.
Configuring the NI 5661 in MAX
Use Measurement & Automation Explorer (MAX) to configure your National Instruments
hardware. MAX informs other programs about which devices reside in the system and how
they are configured. MAX is automatically installed with NI-RFSA.
1. Launch MAX.
2. In the configuration tree, double-click Devices and Interfaces to see the list of installed
devices.
Note If you are using the NI 5661 with the LabVIEW Real-Time Module,
expand Remote Systems. Find your target IP address or name, expand it, and
then expand Devices and Interfaces.
Installed devices appear under the name of their associated chassis.
3. Expand your Chassis tree item.
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MAX lists all devices installed in the chassis. Your default device names may vary.
Note If you do not see your device listed, press <F5> to refresh the list of
installed devices. If the device is still not listed, power off the system, ensure
the device is correctly installed, and restart.
4. Record the device identifier MAX assigns to the hardware. Use this identifier when
programming the NI 5661.
5. Associate the hardware modules that comprise your device.
a) Select the NI 5600 that appears as not configured in the configuration tree.
b) In the Associated Devices section, select the appropriate module from each system
component drop-down listbox.
For the NI 5661, you must associate the NI 5142 IF digitizer module with the
NI 5600 RF downconverter.
c) Click Save in the MAX toolbar.
Note Module associations may be lost when you move the modules to
different chassis slots.
6. Self-test the device modules by selecting the modules in the configuration tree, and
clicking Self-Test in the MAX toolbar. Repeat this step for all modules in your NI 5661
system.
The MAX self-test performs a basic verification of hardware resources.
Related Information
Troubleshooting on page 18
If an issue persists after you complete a troubleshooting procedure, contact NI technical
support or visit ni.com/support.
Refer to the NI RF Vector Signal Analyzers Help for more information about renaming
devices.
NI PXI-5661 Getting Started Guide | © National Instruments | 15

Programming the NI 5661
You can acquire data interactively using the NI-RFSA Soft Front Panel (SFP) or use NI-RFSA
to program your device in the ADE of your choice.
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Table 7. NI 5661 Programming Options
Application
Programming
Interface (API)
Location Description
NI-RFSA SFP Available from the Start menu at
Start»All Programs»National
Instruments»NI-RFSA»NI-RFSA
Soft Front Panel.
NI-RFSA SFP controls,
analyzes, and presents data
similar to stand-alone RF vector
signal analyzers. The
NI-RFSA SFP operates on the
PC, so it provides processing,
storage, and display capabilities.
NI-RFSA
Instrument
Driver
LabVIEW—Available on the
LabVIEW Functions palette at
Measurement I/O»NI-RFSA.
C or LabWindows/CVI—Available at
Program Files»IVI Foundation»
IVI»Drivers»niRFSA.
NI-RFSA configures and
operates the device hardware
and acquires and analyzes data
using LabVIEW VIs or
LabWindows/CVI functions.
After you associate the modules
of the NI 5661 in MAX,
NI-RFSA operates the modules
as a single instrument.
Microsoft Visual C/C++—Use
examples located in the <NIDocDir>
\NI-RFSA\examples directory,
where <NIDocDir> is one of the
following directories:
• Windows 8/7/Vista—Users
\Public\Public Documents
\National Instruments
• Windows XP—Documents and
Settings\All Users
\Documents\National
Instruments
You can modify an NI-RFSA
example to create an application
with Microsoft Visual C/C++,
and all required include and
library files are automatically
added to the project.
Related Information
Refer to the Getting Started with NI-RFSA section of the NI RF Vector Signal Analyzers Help
for detailed instructions about how to acquire data in a specific ADE.
Refer to the Creating an Application with Microsoft Visual C and C++ topic of the NI RF
Vector Signal Analyzers Help if you prefer to manually add all required include and library
files to the project.
NI-RFSA Examples
Examples demonstrate the functionality of the device and serve as programming models and
building blocks for your own applications. The NI Example Finder is a utility available for
NI PXI-5661 Getting Started Guide | © National Instruments | 17

some ADEs that organizes examples into categories and allows you to easily browse and
search installed examples. You can see descriptions and compatible hardware models for each
example or see all the examples compatible with one particular hardware model.
Table 8. Locating NI-RFSA Examples
ADE How to Locate Examples
LabVIEW or
LabWindows/CVI
Locate examples with the NI Example Finder. Within LabVIEW
or LabWindows/CVI, select Help»Find Examples and navigate
to Hardware Input and Output»Modular Instruments.
ANSI C or Microsoft
Visual C/C++
Locate examples in the <NIDocDir>\NI-RFSA\examples
directory, where <NIDocDir> is one of the following directories:
• Windows 8/7/Vista—Users\Public\Public
Documents\National Instruments
• Windows XP—Documents and Settings\All
Users\Documents\National Instruments
Troubleshooting
If an issue persists after you complete a troubleshooting procedure, contact NI technical
support or visit ni.com/support.
Installation
What Should I Do if the NI 5600 RF Downconverter Module
Front Panel POWER LED is Off When the PXI Chassis is On?
If the POWER LED fails to light after you power on the PXI chassis, a problem may exist
with the PXI power rail, a hardware module, or the LED.
1. Disconnect any signals from the PXI module front panel.
2. Power off the PXI chassis.
3. Remove the module from the PXI chassis and inspect it for damage. Do not reinstall a
damaged device.
4. Reinstall the module in a different PXI chassis slot.
5. Power on the PXI chassis.
6. Verify that the device appears in MAX.
7. Reset the device in MAX and perform a self-test.
Why Is the ACCESS LED Off When the Chassis is On?
The LEDs may not light until the device has been configured in MAX. Before proceeding,
verify that the NI 5661 appears in MAX.
If the ACCESS LED fails to light after you power on the chassis, a problem may exist with the
chassis power rails, a hardware module, or the LED.
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Caution Apply external signals only while the NI 5661 is powered on. Applying
external signals while the device is powered off may cause damage.
1. Disconnect any signals from the module front panels.
2. Power off the chassis.
3. Remove the module from the chassis and inspect it for damage. Do not reinstall a
damaged device.
4. Reinstall the module in a different chassis slot.
5. Power on the chassis.
6. Verify that the device appears in MAX.
7. Reset the device in MAX and perform a self-test.
What Should I Do if the NI 5661 Doesn't Appear in MAX?
1. In the MAX configuration tree, click Devices and Interfaces.
2. Expand the Chassis tree to see the list of installed devices, and press <F5> to refresh the
list.
3. If the module is still not listed, power off the system, ensure that all hardware is correctly
installed, and restart the system.
4. Navigate to the Device Manager.
Operating System Description
Windows 8 Right-click the Start screen, and select All apps»Control Panel»
Hardware and Sound»Device Manager.
Windows 7 Select Start»Control Panel»Device Manager.
Windows Vista Select Start»Control Panel»System and Maintenance»Device
Manager.
Windows XP Select Start»Control Panel»System»Hardware»Device
Manager.
5. If you are using a PXI controller, verify that a National Instruments entry appears in the
system device list. Reinstall NI-RFSA and the device if error conditions appear in the list.
If you are using an MXI controller, right-click PCI-to-PCI Bridge, and select Properties
from the shortcut menu to verify that the bridge is enabled.
What Should I Do if the Module Fails the Self-Test?
1. Restart the system.
2. Launch MAX, and perform the self-test again.
3. Power off the chassis.
4. Reinstall the failed module in a different slot.
5. Power on the chassis.
6. Perform the self-test again.
NI PXI-5661 Getting Started Guide | © National Instruments | 19

Configuration
What Should I Do if the Device Does Not Initialize?
Failure to initialize may indicate a problem with module interconnections or with MAX. If the
niRFSA Initialize VI or the niRFSA_init function returns an error and the NI 5661 fails to
initialize, complete the following steps:
1. Reconnect the NI 5661 hardware module front panel cables securely.
2. Power on your system and run the MAX configuration and self-test procedures.
Related Information
Interconnecting the NI 5661 Modules on page 6
Configuring the NI 5661 in MAX on page 14
What Should I Do if the NI 5600 RF Downconverter STATUS
LED Does Not Light?
If the RF vector signal analyzer is programmed to lock to an external reference source or to
the PXI backplane but the STATUS LED light does not indicate a phase-locked status, verify
the following items:
1. Verify that a cable is connected from the external source or the PXI 10 MHZ I/O
connector to the FREQ REF IN connector.
2. Verify that the external source signal is large enough—typically greater than -10 dBm.
3. Verify the external source signal falls within the specified frequency accuracy.
4. If you programmed the RF vector signal analyzer to use the NI 5600 RF downconverter
module internal timebase, verify the following items:
a) Verify that one or more of the local oscillators is phase-locked if the RF vector
signal analyzer measures the frequency incorrectly or detects no signal when one is
supplied.
b) Verify that there is no driver software error and the LED is not damaged if the RF
vector signal analyzer measures the frequency correctly but the LED does not light.
What Should I Do if the NI 5142 IF Digitizer Module Does Not
Phase-Lock to the RF Downconverter Module?
If the IF digitizer module fails to phase-lock to the NI 5600 RF downconverter module
internal reference through the front panel, complete the following steps:
1. Verify that the cable is not faulty and that all cables are connected to the correct
terminals.
2. Verify that there is a reference signal output from the NI 5600 10 MHZ OUT front panel
connectors.
If there is no signal at these output terminals, contact NI technical support or visit ni.com/
support.
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