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Hi John,
Sorry for the delay in response. The SA44B can sweep a larger range than its available RBW. The SA44B can be configured to sweep any range of frequencies within its 1Hz to 4.4GHz range. At a 200MHz span the minimum RBW available will be 6.5kHz.
As for antenna, I’m not familiar with the EMI/EMC antenna market. I would imagine it would depend on what you are attempting to achieve. Are you simply trying to find/characterize interference, an RF probe might be best in this case. If you need to simulate a real EMC test, you will likely need to recreate the test setup as close as possible with a calibrated antenna. I wish I could be more help. Maybe someone else on the board could help you out? You could create a separate topic. I know there have been several users on this board with EMC experience.
Regards,
AndrewHello pmerana,
In the control panel in EMC precompliance, in the ‘trace’ section, you will find the export button which will export the entire sweep (all active sweep segments) to one file. It will export the frequency/amplitude pairs of each sweep segment in order. (Basically exactly as it is plotted). You will need to plot it on a logarithmic x axis to see it as it is shown in Spike. Is this adequate for your needs?
No updates for automatic QP measurements.
Regards,
Andrew November 15, 2017 at 9:10 am in reply to: BB60C "Device Connection Issues Detected" Error in IQ Streaming Hi Blackmore90,
IQ streaming can be more USB throughput sensitive than standard swept analysis.
Here are some troubleshooting ideas.
1) Try a different USB 3.0 port. We have found that not all USB 3.0 ports are created equal.
2) Enable the high performance power option in the “Power Options” menu in the control panel.
3) Try updating your USB 3.0 driver. You can find instructions for Windows 7 machines on our website on the page http://www.signalhound.com/Spike in the FAQ section under the question “The Software Reports “Device not found” (BB60C)”. You will find two driver links. Install one and restart your PC and try again.I look forward to your response.
Regards,
AndrewHello HHonza501,
There are no plans currently to allow the user to change sweep configurations during the recording. If users needed this kind of flexibility on the sweep recordings I would recommend using the API to retrieve sweeps from the device and storing them in a custom file format that suits the customers needs.
You are correct, as you scroll the recording it will move the sweeps into the waterfall. I can see how this wouldn’t be desired. I will make a note of this and potentially resolve this for future versions. Thank you for the feedback.
Let me know if you have additional questions or need clarification.
Regards,
AndrewThat is correct. There is no configurable DSP on the unit, other than the processing associated with individual measurements (sweep/real-time/IQ). The API will be very similar to our other devices.
Regards,
AndrewHi Testpoint,
More information on the SM200A here
https://signalhound.com/sm200a/Let us know if you have follow up questions.
Regards,
AndrewHello Sinisa,
Currently there is no plan to restore the 3D waterfall.
Regards,
AndrewHello Bindinir,
The 3D spectrogram view was removed in a recent release. In that same release we added several new features to the 2D spectrogram, such as large sweep history and marker placement.
I apologize for the inconvenience. If you have additional questions for feedback, please let us know.
Regards,
AndrewHi Jay,
We have seen improvements when using a low latency or real-time kernel. Unfortunately there is no way to determine when this loss occurs. At one point we narrowed it down to a small circular buffer within the FTDI driver, (based on other similar complaints). Several years ago we tested an open source version of the FTDI driver and saw worse results.
Internally using a low latency kernel with a desktop PC (Intel i-series processor), we saw no loss occur over long periods of acquisition (using IQ data to detect data loss). Although, I have had customers report data loss even on low latency kernels with lower power processors.
It would require a moderate/large firmware/software redesign to fully resolve this issue for the Linux platform. We don’t have any plans for this at this time.
Regards,
AndrewJay,
Are you by chance on Linux? I have seen what you describe on Linux, not on Windows. On Linux, the FTDI USB driver does have throughput/buffer issues for high throughput devices.
If you are on Windows, do you know which error code is being returned? The problem corrects itself on the next sweep? You could try a couple troubleshooting steps we suggest for customers who are having USB issues, such as, enabling the “High Performance” power plan in the “Power Options” control panel menu, and disabling any anti-virus you might be running.
Regards,
AndrewHello Petr,
This is possible, you will need to generate a custom IQ file for this output as we don’t have the amplitude offset functionality build into the pulse gen controls.
If you look in the VSG25A installation directory you will find a number of example IQ files which follow the format you can easily load into the VSG software. You can edit them with excel or any text editor easily to create your desired waveform.
Let me know if you have additional questions.
Regards,
AndrewHi Jay,
Thanks for the follow up. I’m glad you got it working.
The official message you will see when the input level is too high is saCompressionWarning(2). If you have any questions about this, let me know.
Regards,
AndrewHi testpoint,
DANL is specified at 0 attenuation and max gain (maximum receiver sensitivity). If you set your reference level to -50 the BB60C will be configured for maximum sensitivity and you will see the DANL you expect.
The way our software currently works, is that the sensitivity (atten/gain) is configured automatically from the reference level. You can control the gain/atten manually in the control panel, you will need to disable the lock on those controls in the file->settings menu (or F11).
Let us know if you have additional questions.
Regards,
AndrewHello jthienel,
Ensure that both gain and atten are non-negative. Any negative number will cause the device to select the gain/atten automatically.
If you are interested, setting the gain/atten to automatic (-1) the default condition, the reference level set in saSetLevel() controls the gain/atten automatically optimizing for signals at or near the reference level. For example, if you know your input signal is -20dBm, setting the reference level to -15 will optimize the device for your measurement. You can get much more consistent results with this method. Maximum sensitivity is achieved with a reference level of -50 or less.
Let me know if you have additional questions.
Regards,
AndrewHello Marzelozz,
In the latest version of Spike, you can place markers on the waterfall plot and measure the time difference between two peaks. You will need to download the latest version of Spike from the Spike landing page here
http://www.signalhound.com/SpikeIf you have questions after installing this and trying the measurement, let us know.
Regards,
AndrewHere is a link to the article if you are interested.
Hello Hhonza501,
Yes, you can launch 2 or more instances of Spike on a single computer. For the BB60C, each Spike instance will alert you that there is more than 1 device connected to the PC and you will need to select a device from the File->Connect menu to open it. When you launch the second Spike instance, just ensure you pick non-opened device. If you try to open a device twice, the second application will ‘steal’ it from the first. (The first instance will see a device disconnect)
Keep in mind 2 or more Spike instances share presets and preferences.
With the BB60C, two or more instances of Spike can consume a lot of resources. You may run into issues on low power ultrabooks or similar. I wouldn’t expect any issues on a standard desktop i5/i7.
Let me know if you have additional questions.
Regards,
AndrewHello Mirek,
Thank you for the follow up.
Regarding the sweep time, I did forget that the SA44 and SA124 units do behave slightly differently. Unfortunately, the SA44/SA124 do not have a selectable sweep time, mainly because there are heavy restrictions on how the unit sweeps which limits us to very specific configurations for given RBWs and spans. These limitations are in hardware/firmware. Because of this, the sweep time parameter is ignored for these devices. Additionally the sweep time printout on the graticule is updated each time the screen is refreshed with new sweep data. So yes, as you mention, for the wide and long sweeps on the SA44/SA124 this number will not represent the total sweep time. Apologies for the confusion. For our BB60C and for narrower sweeps in the SA44/SA124, then the sweep is updated in its entirety each screen update and thus that number is more representative of the overall sweep time.
Regards,
AndrewHello Mirek,
Thank you for the feedback. I can comment on some of your points.
1. The “N points in M ms” display you are referring to shows the number of points in the sweep as well as the amount of time it took to acquire and plot the sweep. ‘M’ in this display is the sweep time.
2A. There is a sweep time control in the ‘Acquisition’ section of the sweep settings control panel. You can find this on the lower right of the application window (assuming you havent moved the control panels from their default position. Keep in mind, for a digital FFT analyzer we define sweep time as the total acquisition time for the sweep. It will not match the sweep time displayed on the graticule as that sweep time will include processing and display time in addition to acquisition time.
2B. See #1 above. ‘N’ in this display is the number of points.
3. You cannot control the number of points directly in our software. Only indirectly through the RBW and span settings. Sweep size is roughly going to be equal to 5*(span/RBW) for the flat top window. Other spectrum analyzers that allow you to control the sweep size are doing so by ‘binning’ adjacent frequency points. We do not do this, so when you go to export/record the sweep you still have the full resolution from the original sweep.
4A. This is a good suggestion but would require additional hardware development to perform and thus we won’t be able to offer this on our current spectrum analyzer line up.
4B. To load the default settings only, use the Presets->Load Default Settings control. This will retain your current measurment mode, but will go back to power on settings. To fully reset to power on state, set the analysis mode to Sweep and hit the “Load Default Settings” file menu selection.
5. This is a good suggestion and we have considered adding this functionality to Spike. We do not have a current time frame on this functionality, but it is something we are very much interested in. Most likely we will add this through a SCPI backend in the Spike software.
6. I agree this will be useful functionality when we add this. If you were not aware, we do have programming interfaces for our spectrum analyzers. They are in the form of C DLLs for Windows. Currently customers who need remote/programmatic control of our receivers use these DLLs to develop out thier needs. I realize this is not as convenience as an ethernet SCPI aware Spike application, but it is something we currently offer.Thank you very much for your feedback. Let me know if you have additional questions or comments.
Regards,
AndrewHi pmerana,
Currently there is no way to automate the quasi peak measurements. It must be done manually as you say. I think this is a good suggestion and it might be something we can add to our software in the future.
Side note: In addition to setting the QP frequency manually, you can select a spur in the peak table list and move the spur frequency to the quasi peak frequency entry with the “Selected Spur to Meter” button. You can do this while the QP measurement is active, and you can move the QP measurement to the meter readings table with the “To List” button while the QP measurement is active as well.
I apologize for the inconvenience. Thank you for the feedback.
Regards,
Andrew