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Hi Chris,
This is a common issue related to graphics card incompatibilities. There are a couple reasons you might see this. The Spike software for certain rendering modes requires the GPU to support OpenGL 2.0 or greater. You will see this issue with either an older GPU that does not support it or sometimes with a newer GPU that might have outdated drivers or drivers that have issues providing this functionality(rare).
Can you let me know what type of PC you are using? Preferrable make/model/CPU model and the GPU model(which you can usually find in the device manager under the display adapters).
I look forward to your response.
Regards,
AndrewHi Volker,
Thanks for the images, I was able to reproduce what you are seeing.
It took me a minute to determine why this is happening and have determined the cause.
In the latest release, we have changed how we plot the limit line. The algorithm we use to test the limit is still the same but instead of plotting what we test against (the interpolated points) we plot the limit line as requested. Since your limit line includes a Spike between two output bins it gives the visual appearance of failing the limit line but in fact the testing is being done on adjacent interpolated bins. If you were to load this limit line into 3.1.11 you will notice the limit line being displayed will not actually come up to -60dBm as we plot only what is being tested against. In fact I included a screen shot of 3.1.11 with the same -60dBm peak being loaded into the limit line and you can see it gets rendered at ~-68dBm because that is the interpolated value that is being tested against. You can also see my input signal below -60dBm.
On review of this, I think we will need to go back to plotting the values tested against rather than the requested limit line.
In conclusion, my current understanding is that we have changed how we are plotting limit lines in the new version but the pass/fail message will match what you would see in the older version 3.1.11.
It might be more beneficial to create a box like limit line that has at least a width of 1 bin (RBW), and then sharply drops off, I think this will create the result you are looking for with more consistency. Currently with a very narrow spike, the high point can easily fall between two bins at which we can’t test at.
If you want to load an older version of the software you can find the link here.
signalhound.com/sigdownloads/Spike/Spike(x64)_3111.zipI will work on restoring the old way of plotting the limit line for the next release.
Let me know if you have follow up questions.
Regards,
AndrewHello Bharath,
We have an FSK demodulation option, but not specifically MSK.
Regards,
AndrewHi Volker,
So I played around with the single tone file you linked, and got it to work as I think you intended, as a test for whether a CW is present. I attached some images, where I zoomed in on the CW and I increased the Div to 15 to see more y-axis.
I did also change the point at 250M to -60 instead of +24 so it’s easier to play with a signal generator at my desk.
I attached three pictures, one where I increased the RBW and you can see it passing. Then two more where I shifted the CW freq and lowered the RBW and it fails both.
The limit line was configured as a min limit line.
Can you provide any more information or maybe a picture showing the scenario you see. If you are able to zoom in on the span as well, it could help me determine why you are unable to reproduce my results.
I will need to look into the roundings, I agree that it is an issue. I will try to get a fix for this for next release. I’ve been editing the files in a text editor for now and it seems to be working.
Edit: I think I see the issue you are experiencing with the line always passing sometimes. One of the issues here is that the spike that you are putting in the limit line is very narrow, and there are only a finite number of points in the sweep, so it is possible that the entirety of the spike and adjacent points fits between two of the sweep points. Basically the lowest RBW you can get away with is what you should use as it will increase the number of points in the sweep giving you more resolution to test again the limit line with.
I look forward to your response.
Regards
Hi Volker,
I’m sorry for the inconvenience. The functionality has changed slightly. The old method had you specify both the min and max amplitude for each frequency (on each line in the file). Now you will want to create two files, a minimum and maximum line and load them into two different limit lines.
The file format has only changed slightly, instead of specifying two amplitudes for a min and max, the single amplitude will be interpreted as a min or max depending on your selection in the limit line menu.
Freq(MHz)1, dBm1
Freq(MHz)2, dBm2
…
Freq(MHz)N, dBmNI attached both files you would load to recreate your old setup and a picture of them working on my screen.
Regards,
AndrewHello Luigi,
Sorry for the difficulty you have experienced.
I can clarify some things. The Spike software does not install/uninstall any drivers for the SA or TG, only the CDM installer/uninstaller. If the Spike software detects and run the SA44, then the driver is installed properly, since the SA shares the same driver with the TG. You cannot connect the TG through the Connect menu in Spike. Spike will only interact with the TG through the Utilities->TG control panel menu or by activating scalar network analysis.
I would try using the Utilities->TG menu to try to control the TG. Additionally, ensure the “Load VCP” checkbox is unchecked for any devices that appear for both the TG and SA in the device manager.
I look forward to your results.
Regards,
AndrewHello Mallaug,
Since Spike also uses the API to retrieve the firmware string and is working for you, it would lead me to believe the issue is probably in the C# interop.
Hopefully someone here has enough C# experience to answer your question. You might also try searching online with search terms like “PInvoke char pointer parameter” or similar. It seems to bring up a lot of relevant results.
Regards,
AndrewDavid,
The bbConfigureProcUnits() refers to the video processing units, “Video Units” in the Spike software. For channel power you will want to set this value to power as you were. The detector should be set to average, and the scale in the bbConfigureAcquisition() function should be set to BB_LOG_SCALE. You have the scale set to BB_LIN_SCALE, which is what changes the output units from dBm to mV.
Regards
Hello David,
I think the biggest issue I see is that since you specified a linear scale output from the API, the sweep is in the units of mV. In the Spike software we specify a log scale output and then convert each sweep bin to mW (power units) before summing them up, and then convert the final result back to dBm. If you want to stay with the linear scale (mV) output from the API, just square each sweep bin before summing.
I will attach a file I have sent others from the Spike software. It has some additional details that are irrelevant here, such as only summing up the power in a range specified by the user, but you will notice the same logic for summing the bins as mW and then dividing by the window bandwidth.
If you aren’t already, you can test the output of your code to the values Spike provides. Assuming similar channel widths, it should match very closely.
Regards,
AndrewHello Carlos,
Thank you for emailing us as well. We will continue to work through your issues via email.
Regards,
AndrewHello JY,
You will need to calibration file for each SA44B you own. If you know the serial numbers for the devices I can help you get links to the calibration files.
Newer SA44B devices store the calibration file on the device itself. If you try running Spike with the other devices, it might automatically find the cal file from either the device or our server.
Regards,
AndrewHi Travis,
KB0NE is correct. There are no discussions for introducing other receivers into the Spike software.
Regards,
AndrewHello JY,
These instructions are for the Spike application.
Download the calibration file for your unit here
https://signalhound.com/custdata/P2054/D20540419.binPlace this file into this directory path.
C:\ProgramData\SignalHound\cal_filesProgramData is a hidden folder so you must “Show Hidden Files/Folders” in the Windows file browser menu. If the SignalHound/cal_files folder does not exist, then go ahead and create it. Once there, rerun Spike.
I believe for the 2.14 application simply place the .bin file in the same directory as the executable in the application directory.
Let me know if you run into any issues.
Regards,
AndrewHello setu_mohta,
There is currently no plans to offer a signal generator with these features.
Regards,
AndrewHello setu_mohta,
We do not have a CSV signal library other than the small number of examples we ship the unit with (~5 examples which indicate more of how to create the CSV files over providing various waveforms)
Regards,
Andrew January 3, 2018 at 9:01 am in reply to: BB60C "Device Connection Issues Detected" Error in IQ Streaming Hello Blackmore90,
Thank you for the reply.
The BB60C generally has had issues running consistently with Xeon processors which is why we only specify the i5/i7 processors in the minimum/recommended PC specs. Generally the issues stem from the USB drivers/support.
If you haven’t already, you can check the Supermicro page for your PC and see if there is any USB/chipset drivers specifically for your machine. I found this page which appears to be the motherboard for the server you linked. You can find a link to the drivers for this motherboard here. “Download the latest drivers and utilities” on the right hand side of the page. There is Intel USB/chipset drivers in the driver list. See if these resolve your issues.
https://www.supermicro.com/products/motherboard/Xeon/C600/X10DRU-X.cfm
I look forward to your response.
Regards,
AndrewHi Catalin,
There are situations (when using the SA44/124) in which the IF overload may not always be reported. Where as with the BB60C which relies on the ADC to tell us of IF overload, the SA overload warning is done by manually checking amplitude values. The ADC does not reliably clamp to the min/max ADC values so we cannot always depend on the large values being clamped properly by the ADC. Additionally, the signal can clamp before it reaches the ADC (in the RF section) and we cannot detect that situation either.
Also note, the Spike software when sweeping will warn you when the signal exceeds the reference level which is not the same as the IF overload warning. This extra warning is not present in zero-span mode.
Sample rates are low enough on the SA devices, you could insert a check on the IQ data to determine if it exceeds some known value (your reference level?).
Let me know if you have additional questions.
Regards,
Andrew December 31, 2017 at 10:18 am in reply to: BB60C "Device Connection Issues Detected" Error in IQ Streaming Hi Blackmore90,
Can you provide the PC make and model? I will see if I can determine what else can be done for your specific PC.
Regards,
AndrewHi hhonza,
Try disabling the video trigger when you are playing back the capture. This will allow you to scroll through the data. When you are playing the signal back and the video trigger is active, it attempts to find triggers in the capture and overrides your manual scrolling.
Once you are able to scroll through the data, try zooming in on the falling edge of that pulse to verify it is a smooth descent.
The trigger position control only affects the display of the IQ data. The pre-trigger setting on the IQ recording toolbar affects how much data before the trigger gets saved.
Let me know if you have additional questions.
Regards,
Andrew December 4, 2017 at 11:38 am in reply to: "Max Input" / "Ref Offset" parameters understanding for EMI precompliance (Yves has contacted us through email)
– Andrew