Archived: NI-RFSA 2.5.2 and NI-RFSA Soft Front Panel 2.5.5 Known Issues

Scaling coefficients returned can differ by up to 1e-10.
For a single record IQ acquisition scaling coefficients obtained from the niRFSA Get Scaling Coefficients VI or the niRFSA_GetScalingCoefficients function could be different from the scaling coefficients obtained from the niRFSA Fetch IQ (1D I16) VI or the niRFSA_FetchIQSingleRecordComplexI16 function. Similarly, for a multi-record IQ acquisition scaling coefficients obtained from the niRFSA Get Scaling Coefficients VI or the niRFSA_GetScalingCoefficients function could be different from the scaling coefficients obtained from the niRFSA Fetch IQ (2D I16) VI or the niRFSA_FetchIQMultiRecordComplexI16 function. The difference in the scaling coefficients can be up to 1e-10.

Workaround: 

There is no workaround for this issue. However, since the difference in coefficients is rather small, this difference does not affect amplitude accuracy for any of the devices supported by NI-RFSA.

In Spectrum acquisition mode, there is no magnitude only equalization performed when doing in-band retuning.
The 5 MHz and 300 kHz filters do not have any magnitude equalization performed in spectrum acquisition mode on the NI PXIe-5665.

Workaround: 

N/A

Specifying a non-zero external gain for the External Gain property or NIRFSA_ATTR_EXTERNAL_GAIN attribute with the Input Isolation Enabled property set to Enabled or the NIRFSA_ATTR_INPUT_ISOLATION attribute set to NIRFSA_VAL_ENABLED causes the driver to return incorrect amplitude parameters.
If you set the Input Isolation Enabled property to Enabled or the NIRFSA_ATTR_INPUT_ISOLATION attribute to NIRFSA_VAL_ENABLED with a non-zero external gain for the External Gain property or NIRFSA_ATTR_EXTERNAL_GAIN attribute, the downconverter gain, fetched IQ, and spectrum data are off by the specified external gain.

Workaround: 

To obtain the actual values of the downconverter gain, fetched IQ, and spectrum data, subtract the external gain from the data returned by the driver.

Specifying a non-zero external gain for the External Gain property or NIRFSA_ATTR_EXTERNAL_GAIN attribute with the Input Isolation Enabled property set to Enabled or the NIRFSA_ATTR_INPUT_ISOLATION attribute set to NIRFSA_VAL_ENABLED causes the driver to return incorrect amplitude parameters.
If you set the Input Isolation Enabled property to Enabled or the NIRFSA_ATTR_INPUT_ISOLATION attribute to NIRFSA_VAL_ENABLED with a non-zero external gain for the External Gain property or NIRFSA_ATTR_EXTERNAL_GAIN attribute, the downconverter gain, fetched IQ, and spectrum data are off by the specified external gain.

Workaround: 

To obtain the actual values of the downconverter gain, fetched IQ, and spectrum data, subtract the external gain from the data returned by the driver.

Reference Clock cannot be exported on the Ref Out terminal on the NI PXIe-5663E.
The following error generates when the NI PXIe-5663E is configured to export the Reference clock to the REF OUT terminal:

The LO returned the following error:

Requested value is not a supported value for this property.

Property: NIRFSG_ATTR_EXPORTED_REF_CLOCK_OUTPUT_TERMINAL
You Have Requested: RefOut, RefOut2
You Can Select: RefOut, RefOut2
Status Code: -223587

Workaround: 

Export the Reference clock to another terminal or downgrade your version of NI-RFSA to NI-RFSA 2.4.2.

Handle leaks can occur when using Spectral Measurements Toolkit 2.6.1 or Modulation Toolkit 4.3.1 and earlier with the NI-5660 API.
When the ni5660 Initialize and ni5660 Close VIs are placed into a loop, Windows handle leaks occur on each iteration of the loop and persist until the top-level VI enters the Idle state. This leak also occurs when a VI containing the ni5660 Initialize and ni5660 Close VIs is executed multiple times by NI TestStand when the LabVIEW Adapter is set to reserve loaded VIs for execution.

Workaround: 

Manual Change Option: 

1. Launch the LabVIEW version where you need to apply the workaround. 
2. Open the VI
   <LabVIEW>
   \vi.lib\addons\Modulation\Analog\support\IQutilites\mod_IQ ViRef Table.vi. 
3. Open File»VI Properties.
4. Select the Execution as the Category pull-down menu. 
5. Remove a checkmark from the Reentrant execution checkbox.
6. Click OK.
7. Save the VI and close LabVIEW. 

Note: You must make this change for each installed location and version of LabVIEW on the disk where the Spectral Measurements Toolkit and/or the Modulation Toolkit are installed.

Upgrade option: Install a newer version of the Spectral Measurements Toolkit or of the Modulation Toolkit.

• Trigger Bus 1: PXI Slots 1, 2, 3, 4, 5, and 6
• Trigger Bus 2: PXI Slots 7, 8, 9, 10, 11, and 12
• Trigger Bus 3: PXI Slots 13, 14, 15, 16, 17, and 18

• Change the location of the source and destination devices for the hardware route such that both of them lie in the same trigger bus.
• Since this error is intermittent, first retry the same route because it may succeed. In LabVIEW, you can retry by conditionally detecting error -26981, clearing the error, and attempting to reserve the same route again.

• Using a narrower resolution bandwidth.
• Disabling the dither.
• Choosing a different FFT window type. This solution may be less effective than the previous solutions, depending on the resolution bandwidth.

Mismatch between the analyzed range and visual indication on the UI when you set the Delay for an IQ power edge trigger to a non-zero value.
When you set the Delay for an IQ power edge trigger to a non-zero value, you set the starting point of the acquisition as a delay from the trigger, which alters the starting time. However, the calculation code assumes a starting time of zero. Therefore, the analyzed range does not match the visual indication on the UI. This issue is likely to occur because the default trigger setting for TxP includes an unaccounted non-zero trigger delay.

Workaround: 

Set the Measurement Method to Above Threshold Level or set the trigger delay to zero.

In SEM, the Soft Front Panel sometimes disables the IQ Power Edge softkey when it shouldn't.
The SFP disables the IQ Power Edge softkey in the Trigger menu when the configured span is greater than the current instantaneous bandwidth of the device. However, in SEM, the actual span used for this calculation does not match the configured span. As a result, the SFP disables the IQ Power Edge softkey even though it should be enabled based on the current configuration.

Workaround: 

Turn the SEM measurement off by clicking the Meas»All Meas Off softkeys. Set your span to the same value as the span used in SEM. Turn SEM back on to enable the IQ Power Edge softkey.

In Zero Span with a marker enabled, if you change acquisition time, the keypad cannot change the marker position.
In Zero Span with a marker enabled, if you change the acquisition time, the keypad cannot set a marker position for the existing marker.

Workaround: 

Use the arrow keys or knob to enter a new zero span marker position. After using the arrow keys or knob to change the marker position, the keypad can be used.

In CCDF, you cannot set the delta marker to a trace different from the reference marker.
When performing a CCDF measurement, if you set the delta marker to a trace different than the reference marker trace, the indicators show that the marker is on the trace you selected but the marker on the graph and the reported value remain linked to the reference marker trace.

Workaround: 

Set two markers to normal mode and manually calculate the difference using the reported values in the marker table.

A delay occurs if you use the mouse to move a marker when there are many points on the graph.
In Spectrum mode, with a large span to RBW ratio or in Zero Span mode with a large RBW or acquisition time, when you enable a marker and move it using the mouse, events queue up and there is a delay until all the events are processed. You may also experience a delay when clicking the arrow keys.

Workaround: 

Change the marker position by entering a new marker value using the keypad instead of the mouse or arrow keys.

When you recall a configuration with RF Coupling set to DC, the SFP does not display a warning when it should.
When RF Coupling is set to DC (DC block removed), the NI PXIe-5665 can be damaged when DC signals are applied directly to the RF IN connector. This warning does not display under the following conditions: 

1. Loading a configuration file for the PXIe-5665 with RF Coupling set to DC. 
2. Loading a configuration file for the PXIe-5665 with a Start Frequency less than 10 MHz.

Workaround: 

For condition 1, toggle the RF Coupling to AC and then back to DC after loading the file and the warning will appear. 

For condition 2, toggle the Start frequency to another value and then back after loading the file and the warning will appear.

In SEM, the SFP does not coerce the Integration BW when you set the Span of the Ref Channel to a value less than the Integration BW.
In SEM, if you change the Span of the Ref Channel to a value less than the Integration BW, the Integration BW value remains unchanged. As a result, a span equal to the Integration BW is acquired to accommodate the Integration BW value.

Workaround: 

Set the Integration BW value to a value less than or equal to the Span value.

RBW and Step Frequency can be set lower than the minimum limit in SEM measurement.
For an SEM measurement, the minimum value for RBW is 100 Hz and the minimum value for Step Frequency is 2 kHz. If you are in manual mode, you can specify RBW and Step Frequency values that are less than the minimum values. The user interface will display the values you specify. However, the NI-RFSA SFP does not support values that are less than the limits, so the actual device settings are not reflected by the user interface.

Workaround: 

N/A

The offset value displayed by the Select Offset button is incorrect in certain cases.
For adjacent channel power measurements and spectral emission mask measurements, if you specify an offset value between 13 and 15 using the Select Offset button, the button displays an offset value that is incremented by one. The NI-RFSA SFP uses the offset value that you specify in the Select Offset button to configure the offset, but displays an incorrect value. For example, if you specify 13, the Select Offset button displays a value of 14, but the Soft Front Panel displays the configuration, for the offset of 13.

Workaround: 

Use the value that you specify in the Select Offset button for editing and viewing the configurations. Ignore the value displayed in the Select Offset button.