Knowledge Base

Best Practices PIM Testing

What is Passive Intermodulation (PIM)?

Passive Intermodulation (PIM) is similar to active Intermodulation (IM) but occurs in passive devices. PIM occurs whenever RF signals at two or more frequencies are simultaneously present in a conductor of RF energy. Every passive RF device generates passive IM products when more than one frequency is present in the device. The signals are mixed by the non-linear properties of junctions between dissimilar materials. Typically, the odd-ordered products (e.g. IM3=2*F1-F2) can be very problematic should they fall within an uplink or receive band of the base station because they appear to the receiver's random noise floor.

What are the typical causes of PIM?

In RF components (antennas, cables, filters, etc.), there are typically three causes:

Poor mechanical junctions in the RF path
RF components fabricated with materials which exhibit some level of hysteresis (e.g., stainless steel)
Contaminated surfaces or contacts within the RF path. Examples might include flux (which can attract other contaminants) and metallic particles from the machining process.

In an antenna system, any passive components installed between the high-power amplifiers and the receiver filter can generate significant levels of passive IM.

Passive IM is not limited to the components internal to the antenna system! It can also be generated externally to the antenna system by nearby PIM sources (such as metallic objects) in the direct beam of the transmit antenna.

What is meant by "IM3" and "IM5" ?

This annotation is commonly used to specify the order of the IM product being discussed. The IM stands for "intermodulation." The numeric value that follows is the sum of the integer multipliers used for each of the two parent tones to realize the given IM product. This is best understood by reviewing the following table:

IM Calculation	IM Order
2F1 ± 1F2 = FIM3	Third Order (2+1=IM3)
3F1 ± 2F2 = FIM5	Fifth Order (3+2=IM5)
4F1 ± 3F2 = FIM7	Seventh Order (4+3=IM7)
5F1 ± 4F2 = FIM9	Ninth Order (5+4=IM9)

Most commonly, the lower-order tones are of the largest magnitude. However, in frequency-selective systems, an IM5 product might appear larger to the receiver than an IM3 product.

What is a "good" PIM level?

The required PIM performance for a given RF device is a strong function of where that device is located in the final system. For example, an antenna must have excellent PIM performance as the PIM generated in the antenna is both received and radiated by the base station. Further, the transmit antenna is subjected to nearly the full carrier power of the base station. On the other hand, the PIM performance of a receive "clean-up" filter need not be so stringent. For example, this filter might be located on the other side of a diplexer, thus preventing the full carrier power level from reaching its input connector.
Ultimately, it is up to the antenna system designer to specify the maximum acceptable PIM level and carrier power levels. Commonly seen specifications for antennas are -100 to -110dBm IM3 levels with two +43dBm (20 Watt) per carrier tones.

Does PIM vary with power level?

Yes. However, the relationship between the generated PIM power level and the parent carrier power levels is not always straightforward.

In simple, broadband devices terminated into a broadband termination, the IM3 response typically increases approximately 3 dB for every one dB in carrier power level (assuming equal carrier powers). However, many factors tend to work against this nice, simple relationship. These include:

High return loss values at n*F1 and/or m*F2
Extreme slope variations on the hysteresis curves associated with ferrite devices
Non-Linear behavior of electromechanical junctions as they approach a breakdown potential
The interaction of multiple IM sources as the impedance of each IM source changes with incident power level

In general, as the transmitter power increases, the importance of PIM on the overall system performance becomes of increasing concern. As a TDD system fills available frequency and time channel slots, or as an LTE system increases forward power levels to increase capacity, PIM levels typically increase.

Does PIM very with frequency?

It depends. One postulate is that a single IM source which is located at a single point (not spatially distributed) and is matched in impedance to the incident transmission line (or source of stimulus RF energy) generates frequency-independent IM isotropically. This is the analog of the classical "Point Source" of RF in antenna theory.

Given that this point source of PIM exists (at least theoretically), real-world RF devices can be modeled as being comprised of multiple PIM sources. These sources generate IM which has a phase relationship with the parent RF carriers. Once the PIM is generated at each point source within the device, the PIM signals themselves can vectorally combine (either constructively or destructively) to produce a composite PIM response. The phase relationship between the PIM sources will depend upon their physical separation, the dielectric through which the RF must travel between the sources, and the frequency of the parent carriers.

Given that all real world devices have more than one source of PIM, it is quite probable that the device will have a frequency-dependent PIM response. However,

if the device is electrically small, or
if the bandwidth of interest is relatively small compared to the device under test, or
if the device is dominated by a single, large IM source the measured frequency response may appear frequency independent.

Can I use a 1800MHz Band PIM test system to measure cables for use in the 900MHz cellular band?

Even though electrically long (more than one-half wavelength) cables can have a frequency-dependent PIM response in the reverse direction, the periodicity of the ripple can quite often be related directly to the electrical length of the cable assembly. Yes, the cable PIM response is frequency dependent. However, if the cable assembly PIM is measured across a swept-frequency bandwidth that includes both peaks and nulls, the worst-case combination of PIM sources can be captured across the test band.

So long as the individual sources of PIM do not change in magnitude dramatically with frequency and so long as the loss of the cable assembly does not change appreciably with frequency, there is a good chance that the PIM results measured at 1800MHz will be representative of the performance expected at 900MHz.

This topic does bring up an interesting note, however. As the carrier frequencies increase, the RF skin depth on the conductors of the device-under-test tends to decrease. For equal carrier powers, the current density at 1800MHz will be higher than at 900MHz. For this reason, testing a cable at 900 MHz may produce a PIM result which is better than the results which might be obtained if the same cable were tested at 1800 MHz.

The bottom line is as follows: To be absolutely certain of the PIM level for a cable assembly in a given band, you should test in that band. To characterize the approximate performance of a cable assembly (or the integrity of the mechanical connector-cable interfaces), testing in one band will most likely yield results which are representative of the overall cable performance.

How is PIM specified?

Passive IM is typically specified in absolute power (units of dBm) or power relative to only one of the test tones (units of dBc). For example, a -110dBm IM signal caused by two +43dBm tones is also specified as a -153dBc IM level. In the case of unequal carrier power levels, Kaelus has established the convention that units of dBc are relative to the largest of the incident carriers.

It is important to note that a carrier power level must always be specified with the given PIM performance level. This applies equally to PIM performance specified in units of dBm and dBc.

My PIM test system has a noise floor of -140dBm. Can I measure a -140dBm response?

There is a clear distinction between random noise floor (kTBF) and the "PIM Noise Floor." The latter is more accurately restated as "Residual IM Level". These two parameters are discussed below:

The noise floor of the PIM test system is typically defined as the mean value of the measured signal when the receiver is terminated into 50 Ohms and the RF is turned off. If there is a coupling mechanism for noise from the high power amplifiers to appear in the receiver, this source of noise must also be included in the noise floor test. Noise is random and is typically due to a combination of phase noise in the local oscillator, kTBF noise from the receiver's pre-amplifier(s), and noise from the transmitter. The noise floor of a PIM test receiver (or spectrum analyzer/LNA combination) typically varies from approximately -120dBm to -140dBm depending upon the selected averaging level (or resolution bandwidth). You cannot make a meaningful IM measurement at a level below the noise floor of the receiver.

The residual IM level of the analyzer is caused by internally generated IM within the analyzer's cabling, internal connectors, filters, and duplexers. This level is typically larger than the noise floor of the receiver for the third-order IM product (IM3). When an IM measurement is performed on a DUT whose true IM level is near that of the analyzer, significant measurement errors can occur. This is because the residual IM of the analyzer vectorially combines with the true IM of the device-under-test thus producing a measurement with a high uncertainty level. The residual IM level of a test system can be reduced through the use of high-quality diplexers, filters, and carefully constructed, Low-PIM interconnecting cables.

Note: Averaging (or reducing the resolution bandwidth of a spectrum analyzer) cannot reduce the residual IM level. Averaging is only useful in reducing the level of the receiver noise floor. For the most efficient measurement time, and to maximize the test system's responsiveness to transient PIM, use only enough averaging (or use the widest possible resolution bandwidth) to maintain the receiver noise floor at least 10 dB below the expect minimum PIM level.

Does PIM change with time?

Possibly: Two types of PIM generation are typically found. The first type is of a "burst" nature and is commonly associated with the periodic breakdown of poor mechanical junctions exposed to high RF power levels. With this type of PIM, the IM will appear as a short (less than 1 second) burst of broadband, noise-like energy. On some devices and systems, these bursts have been measured at random intervals from 2 or 3 seconds to several hours.

The second type of PIM generation is a more steady state, and coherent in nature. RF heating within RF conductors and around RF interfaces can causes minute changes in the contact integrity. The result is a PIM level which changes with time. A classic example of this can be found by measuring the PIM from a cable assembly which is poorly constructed or has been subjected to mechanical stress. The PIM performance of the cable assembly may appear quite good at first, only to degrade as the assembly heats up. Interesting enough, the opposite has been found to happen. The cable assembly is poor at first, but as the RF heating causes the mechanical interfaces to expand (and compress), the PIM performance improves with time.

Consider an operational and fielded base station. Wind, Rain, and Sun-induced thermal cycling are all at work to continuously stress the mechanical interfaces within the antenna, the cable assemblies, and the connections to the shelter. As the sun rises and heats the RF connections. The PIM levels can rise (or fall) if the cables, connectors, and antennas are not functioning properly. The result can be increased levels of IM only at certain times of the day.

Is there a difference in forward and reverse (reflected) IM levels?

Because the intermodulation signals created at various PIM sources within an assembly are vectorial in nature, their relative phase relationships will determine the overall magnitude of (scalar) PIM measured at a particular location in a Device Under Test. Using the model developed in the application note Measuring the Passive Intermodulation Performance of RF Cable Assemblies, we find that all the IM responses arrive in-phase at Port 2 of a through IM measurement, independent of the IM frequency, while the reflected IM response present at Port 1 is a combination of the Port 1 response plus a phase-shifted response from the IM sources at Port 2. Because there is a vector combination of IM sources with differing phases, it is expected that the reflected IM response is a function of both frequency and the electrical length of the assembly.

In the real world, however, the forward IM response may not measure as being frequency independent and may not be the worst-case IM response. This is due to differences between the real world and the very simple model used in the above reference. Using more complex models which account for complex impedances and losses at not only the IM frequencies, but also at the harmonics of the carrier frequencies is a step forward towards more accurately predicting the results of a passive IM measurement.

Is there a difference in IM with carrier frequency separation?

Should RF sources be "phase locked" to "align" the carriers?

Not if you are testing with two tones. When two carrier tones are used, the relative rate of phaser rotation between the carriers is determined by the frequency separation. The carriers will periodically combine in and then out of phase at a fixed rate for the given frequency separation. Phase locking the carriers together will force the carriers to cross at a known instant in time, relative to the phase of one of the carriers. However, this won't impact the magnitude of the generated PIM levels.

If three or more carriers are utilized for testing, the phase of the third carrier now becomes important. By phase locking the three carriers together, and adjusting their relative phases, a specific phase point on the third carrier can be made to align with a known phase crossing point of the first two carriers. This could be used, for example, to establish a worst-case current density at a set of fixed frequencies at a specific point within the device-under-test.

Whether you are using 2, 3, or 100 carriers to perform PIM testing, it is good practice to connect the clocks together to minimize the impact of RF frequency drift on the measurement. This is especially important if you are using a very narrow receiver to perform the PIM testing.

What is the difference between a 16-tone and a 2-tone PIM test?

When measuring PIM with a 2-tone test, there is only one IM response of each order which is of interest. This is in contrast to a 16-tone PIM measurement. In this case, there is a "picket-fence" of, say, IM3 responses to choose from displayed on the spectrum analyzer. Depending upon the characteristics of the device- under-test, the picket-fence may be flat, or have a more complex shape. Typically, the largest of the observed responses of which is reported as the device's PIM level.

The 16-tone test has the advantage of allowing the device's PIM frequency response to be observed in a single measurement. This same frequency response display is obtained with the Kaelus Passive IM Analyzer (or other computer-controlled PIM systems) by sweeping the carriers across a pre-defined band, much the same as a conventional network analysis measurement.

Comparing the 16-tone and 2-tone measurement results is a difficult task. Some users have reported the swept 2-tone test is much more difficult to pass, while others say the 16-tone test is more rigorous. As results from comparison testing become available, Kaelus will continue to update this FAQ.

Why should I care about PIM?

Ultimately, it is the performance of the integrated base station that is important. Although most wireless transmit and receive frequency bands are carefully selected to avoid landing the largest IM products within the receive band, self-generated higher order products (IM5, 7, 9) do land within some communication bands. More frequently, IM products from a nearby (or co-located) competitor's site can become troublesome sources of interference.

To the receiver, PIM products appear as interference. Once the PIM power level rises above the random (kTBF) noise floor of the receiver, the system C/I becomes adversely impacted. Because PIM products typically increase significantly as the average transmit power level increases, the impact of PIM on a base station may only become significant when the base station becomes fully loaded. Just when the most capacity is needed, passive IM level can rise and interfere with normal base station operation.

Are there measurement standards for passive IM?

The International Electrotechnical Commission (IEC) has formed a Technical Committee (TC46/WG6). The assigned task of this committee is as follows:

"To prepare test methods and to investigate relevant limits, for Passive Intermodulation in the RF and microwave frequency range for passive components (i.e. connectors, cables, cable assemblies, waveguide assemblies and components...). To closely liaise with TC 102 for matters relevant to antennas and with SC 48B for connectors with respect to PIM. To liaise with other relevant committees, subcommittees, working groups, organizations and individuals, in order to ensure the widest appropriate awareness of, and the greatest relevant participation in and contribution to the work being carried out."

This group has been meeting for several years, and the first release of a standards document is imminent. Contact the IEC http://www.iec.ch for additional information or to obtain a copy of this document when it becomes available.

Why doesn't my low IM termination have a calibration certificate?

Only a return loss measurement on the Termination uses equipment (network analyzer) that is traceable by the ANSI standard. We do not do a return loss measurement unless the Termination has failed. No test equipment or serial number, that is traceable, is on the calibration certificate. It is the level of residual PIM of my equipment. There is no provision on the calibration certification for traceability to the Summitek equipment.

The engineering department has reviewed the calibration status of the SI-20A and SI-30A Terminations. They have concluded that a calibration certificate and calibration requirement for the Terminations does not apply. We no longer issue calibration certificates for Low IM Terminations as of January 1, 2008 and you should discard any certificates that you have. Only a verification certificate/plot is now issued for new Terminations.

How do I use my PIM source?

Why do I see high IM levels with the RF turned off?

The unit has unstable readings or IM spikes with the RF off has been due to stray RF. The unit is picking up a nearby cell tower or cell phone and the signals can get very high. This can get so bad that it’s impossible to do a reliable test because you can’t separate the PIM from the stray stuff. Stray RF can occur with an open port at the analyzer or with the analyzer connected to cable runs/antenna at the base station. Sometimes you can point the antenna around and get an idea of where it is coming from.

The cable in the low IM termination is not shorted at the end and sometimes the load itself will act as an antenna. You may pickup stray RF with the load on the unit. The PIM source has a resistive load and will make a good termination. Put the PIM source on the analyzer and keep the RF turned off. If the IM spikes/instability stop, then the problem is stray RF. You can also use the spectrum mode to listen and see the stray RF.

IM measurements are unstable, how do I fix this problem?

Why is my unit always giving me a good reading 100 percent of the time?

Portable PIM Equipment

iQA HOW TO: How do I save reports from the iQA to my USB or laptop?

iQA HOW TO: What is the difference between "PIM level measurement" and "peak PIM measurement" as shown on the iQA report?

The PIM Level Measurement and test point label can be added to the report by pressing “Record Point” during the period while the RF is on. Or, you may wait until the RF times out and then press the Record Point button. In both cases, the PIM level that was last seen by the instrument before the RF turned off will be the level that appears in the report.

The Peak PIM level will reflect the highest IM level that occurred while the RF was turned on. This may be the same as the PIM Level Measurement or higher, depending on how stable the IM source was during the measurement period.

iQA HOW TO: How do you change between dBm and dBc values on the iQA?

iQA HOW TO: How do I save a screen shot and transfer it off of the iQA?

When the camera icon is pressed, a screen shot is saved in .png format to the root D: drive (there is no option to save it in any other location). There are two ways to retrieve the picture:

Go to the Configure menu from the main screen and then press “Exit iQA”. This will shut down the iQA application and the normal Windows desktop will appear. You are now able to use Windows Explorer and browse to the root D: drive where the screenshots are located. The files may then be cut, copied, pasted or sent to a USB drive. (Hint: a USB keyboard and mouse makes this operation easier and if small USB hub is used, all three USB devices can be used at once.)
A “File Transfer” or “File Share” cable may be used to connect to another computer. It connects to the USB port on the iQA and no installation software is required:

Drag and drop files in either direction
Group copy files
Delete files
Runs in parallel to the iQA application. This means you can save a report on the iQA and immediately transfer to your PC without ever exiting the iQA application.

iQA OPERATIONAL: Is the test gear sensitive to temperature?

iQA OPERATIONAL: Can I use all three USB hubs at the same time?

iQA TROUBLESHOOTING: Upon powering up, the iQA says "reboot and select proper boot devise or insert boot media in selected boot devise and press a key". What does this mean?

iQA TROUBLESHOOTING: The iQA touchscreen appears to need calibration, what is the process?

For Touch Screen calibration, do not use fingertip; a small plastic pointer is required for accuracy.

Double click PM icon in lower right
Select Control Panel from drop down menu.
Pen Mount control panel opens.
Under Device Tab, highlight “Pen Mount 9000 RS232”.
Click Configure button and select Standard Calibration button.
Or, if Pen mount is not in the system tray
Using windows explorer, open program files, open Pen Mount Universal Driver folder.
Double click DMCCTRL and Pen Mount control panel opens.
Under Device Tab, highlight “Pen Mount 9000 RS232”.
Click Configure button and select Standard Calibration button

iQA TROUBLESHOOTING: Why is the RED RF-LED light on my unit flashing?

iQA TROUBLESHOOTING: Why is my alarm constantly going off?

iQA TROUBLESHOOTING: Why does my unit give me a constant shock when everything is connected correctly?

iQA TROUBLESHOOTING: I just received by unit back from calibration but it is stating that the unit needs to be calibrated again. How can the problem be resolved?

iQA TROUBLESHOOTING: Why do I get a continuous error prompt with my RTF module?

iQA TROUBLESHOOTING: iQA will not boot up while a USB drive is inserted in one of the ports and displays the error message: Invalid System Disk, Replace disk and press any key. How is this resolved?

iHA TROUBLESHOOTING: Unable to connect to iHA in Windows 7 to due communications error. How do I resolve the issue?

Make sure the COM port you’ve selected is the appropriate port for your COM device (i.e. a USB-to-Serial adapter cable might be on COM7, or COM 27). Also check your device properties to ensure COM settings are set to the following:

Bits per second: 9600
Data Bits: 8
Parity: None
Stop bits: 1
Flow Control: None

Also, if you are using a serial adapter (i.e. USB-to-Serial), make sure the adapter is compatible with your operating system (many adapters are not compatible with Windows 7 operating system). Check the vendor website or documentation to confirm compatibility.

iHA TROUBLESHOOTING: Battery will not charge. What is the resolution?

iHA TROUBLESHOOTING: Using Windows XP, iHA remote terminal software will not open and displays error message. What is the resolution?

It is possible that all of the test point labels have been deleted, which in the current version of software causes the application to shut down on starting. A work around until the next release is to delete the usersiHAconfig file. There should be one or more folders starting with iHA_interface.exe located on XP in the following location: C:\documentsandsettings\"username"\appdata\local\kaelus\.

Delete all of these folders to rectify the problem. We are working on a new release to address the issue.

iHA HOW TO: How do I change from dBm to dBc?

Bench PIM Equipment

BPIM TROUBLESHOOTING: Analyzer cannot produce the requested power carrier levels. Carrier status is reporting UNLEVELED or CHECK TX?

When carrier power levels fall outside of your analyzer’s specification, the software produces an UNLEVELED or CHECK TX error to reflect this error condition. Check to make sure all ports on the back of the analyzer are properly connected (on D series analyzers check the Detector cable between the PA and RF modules). If problems continue, the unit may need to be returned for repair. Please contact support for additional assistance.

BPIM TROUBLESHOOTING: What instrument device drivers are required for my analyzer?

i. D and E series BPIM analyzers require National Instruments DAQmx drivers to be installed to your machine. The latest version of these drivers may be downloaded directly from National Instruments (http://www.ni.com).

ii. A and B series BPIM analyzers require National Instruments Traditional NI-DAQ drivers to be installed to your machine. The latest version of these drivers (v7.4.4) may be downloaded directly from National Instruments (http://www.ni.com).

BPIM TROUBLESHOOTING: Analyzer cannot be found using BPIM software version 7.9. I have verified that NI-DAQ devices are setup properly according to the user manual.

Some newer versions of the Traditional NI-DAQ drivers also include a version of NI-DAQmx which causes the software to look for a D series PIM analyzer by mistake. This problem can be corrected by making the following modification to the Windows registry.

Open Windows Registry Editor (Run regedit.exe)
Browse to the registry key “Computer\HKEY_LOCAL_MACHINE\SOFTWARE\National Instruments\NI-DAQmx\CurrentVersion
Rename the “Version” value to “xVersion” (right-mouse-click, and press Rename)

BPIM TROUBLESHOOTING: My power amplifier will not power up. How do I check the fuses?

BPIM TROUBLESHOOTING: Why does my Virtual Front Panel show a high noise floor after its connected to the controller that was previously measuring with an E model?

BPIM TROUBLESHOOTING: My system shows invalid configuration file error when i start the VFP?

The invalid configuration file message is related to the VFP attempting to load a configuration which will not work for the connected analyzer. The message relates to the “instrument state” of the VFP and tries to automatically configure the power, frequency, reference level and various other settings in the VFP. This is not a serious error and the correct configuration (or “Default Configuration”) can be manually selected after you click OK. The VFP configuration file should be automatically corrected upon exit, and will not throw the error again the next time the program is opened.

BPIM TROUBLESHOOTING: The VFP will not connect with my D model system?

Check NI-MAX (National Instruments’ Measurement and Automation Explorer) to confirm all DAQmx devices are present. If devices are displayed with a warning icon (yellow triangle) this may indicate that there is a potential problem communicating with the USB boards. This warning may be related to a Windows Hotfix which is available through your Microsoft Windows Update. The following instructions demonstrate how to apply the hotfix to your PC. The warning errors will go away following a reboot.

Important Notice: Microsoft Hotfix for USB DAQ Devices and Windows XP

If you are using NI-DAQmx with a USB DAQ device on Windows XP, you should install the Microsoft hotfix reported in Microsoft Knowledge Base 969238.

BPIM TROUBLESHOOTING: The VFP is displaying error code "-50405" when attempting to make a measurement on my D or E series analyzer?

The USB/interface cards in the FE and PA modules are sometimes affected by a static discharge shock. The discharge can cause the USB card to lose connection and give the error you see. On the early USB cards, we found that NI did not properly ground the connector shield. To re-connect the USB card and clear the error, close the VFP and unplug the USB cable at the FE module. Wait a couple of seconds and plug the USB cable back in, listening for the recognition ding. The VFP should open normally. Preventative measures such as proper grounding and the use of ESD wrist straps may alleviate these errors. If the error persists the unit may require an engineering fix which can be installed at the nearest service facility.

BPIM TROUBLESHOOTING: The VFP is unable to connect to my PIM hardware (error 63).

Sometimes the PIM Web Engine (or Hardware Engine) is mistakenly blocked by the windows firewall (even when it’s been disabled). There’s a fairly easy way to unblock the process through the Windows firewall settings panel. Follow these instructions to reset the PIM Web Engine (or Hardware Engine) in the Windows firewall settings, and it should work again.

Open the windows “Control Panel” (Start Control Panel)
Open the “Windows Firewall” control panel by double clicking the appropriate icon.
Select the “Exceptions” tab on the firewall dialog window.
Find the item in the list that is labeled either “BPIM Web Engine”, “PIMHW”, or “PIM Hardware Engine”, select it, then delete it (press Yes to confirm deletion)
Next, click the “Add Program” button
A dialog will appear for you to browse for a program. Press the “Browse” button
Browse to the PIM program directory (“C:\Program Files\Kaelus\BPIM Suite”, or “c:\program files\summitek\pim” for legacy BPIM analyzers)? and double click the “BPIM Web Engine”, or “pimhw” application
Browse to the PIM program directory (c:\program files\Kaelus\pim)? and double click the “pimhw” application
Press OK to the Add Program dialog, then press OK to the Windows Firewall dialog.

This should reset the program access restrictions in Windows firewall and allow the program to be visible again.

BPIM TROUBLESHOOTING: Where are my BPIM calibration files stored on the system?

BPIM TROUBLESHOOTING: How do I configure my SW module to connect with my various PIM module components?

Follow these instructions to make sure you have all of your switch positions mapped according to your unit serial numbers.

Exit the Virtual Front Panel (VFP) software.
Double click the BPIM Web Engine icon from your system tray (far right-hand corner of your START bar in Windows). If the window appears without buttons, minimize it and open it again by double clicking the icon from the system tray once more.
Click the Advanced Options button to show the configuration options.
Click the Switch Config button to enter the SW Module switch map configuration utility.
In the Switch map configuration utility, you will select the SW module by serial number (it will be the only one present), then select the 0710-PA module as the “Shared Module” (again by serial number). For your reference, a blank view of the SW Path Map GUI is shown below.
The serial numbers you select for A, B, and C, must match the serial numbers on the back of each module to properly function.
Once all paths have been mapped according to your setup, press the “Save & Exit” button to exit the utility.
Now you may start the VFP and switch between your various PIM bands.

BPIM TROUBLESHOOTING: How can I use the BPIM API Programming protocol to control my legacy A or B series analyzer?

Legacy A|B series BPIM analyzers can be controlled using the Advanced Programming Interface protocol which is provided through the latest BPIM software release. Due to the requirement for Traditional-DAQ device drivers for the legacy BPIM analyzers, the system configuration consists of a hybrid installation of both legacy PIM software (i.e. BPIM Distribution Software v7.9), and the latest BPIM software release (both are available for download from our website). The following procedure demonstrates the process for configuring your Legacy PIM system for control using the BPIM API.

Install National Instruments’ Traditional DAQ drivers v7.4.4
Install BPIM Software v7.9 (available from www.kaelus.com).
a. NOTE: Select installation directory to be “c:\Program Files\Kaelus\BPIM 7.9”)
Reboot the PC.
Copy calibration files for your instrument to “c:\Program Files\Kaelus\BPIM 7.9”.
Install the latest version of the BPIM Software Suite including DAQmx drivers (available from www.kaelus.com).
Reboot the PC.
Check again to make sure the VFP v7.9 is still operating correctly.
a. NOTE: In some instances, an error will occur at startup of the VFP which causes the PIM analyzer not to be discovered. To resolve this error you must rename a key in the Windows Registry as detailed below:
- Open Windows Registry Editor (run “regedit”)
- Browse to the branch “Computer\HKEY_LOCAL_MACHINE\SOFTWARE\National Instruments\NI-DAQmx\CurrentVersion”
- Rename the “Version” key to read “xVersion” (i.e. right-click + Rename)

Once you’ve confirmed that the VFP software v7.9 continues to operate correctly then you may leverage the BPIM API protocol language to control your legacy BPIM analyzer programmatically and collect measurement data in your customized application.