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Hi Ivan,
The ‘jumps’ you are seeing are due to different calibration settings being applied to the individual IF paths. Each IF is 20MHz wide and each IF has its own set of corrections. For the TG sweeps we did not optimize the bands for overall flatness, as once you store thru the correction differences are stored in the offset and the trace should be flat. Your measurements will not be affected as long as the store through has been performed.
Regards,
A.J.Hi Alex,
Thank you very much for the feedback. I will try to resolve the FM deviation scale issue for the next release. This is a bug that many others have mentioned now. Also thank you for mentioning the preset issue. I will add it to the request list and hopefully be able to address it soon.
Regards,
A.J.Hi Donfrank,
Please contact us at 1-800-260-TEST. I am at extension 2. There are a few reasons a firmware update might have failed in this fashion. We can talk about what we can do to resolve this. We are available to talk between 8-3 PST. If you are unable to call during that time, email me at aj@signalhound.com and we can continue this discussion via email.
Regards,
A.J.Hello Ivan,
Excellent feedback and suggestions. We are aware of the limitations of Zero-Span and hope we can address them in the future. We are also aware of the need for triggering in modulation analysis. As always, I cannot specify any time frame for when we might address these issues, but we do record all suggestions and feedback and use them when making decisions about what to pursue next. We very much appreciate it.
You might be interested to know that there is very basic I/Q capture functionality in Zero-Span mode along the bottom of the screen. It allows you to save a burst I/Q capture to a file as CSV. You would then need to convert it to an amplitude/phase/frequency value in a spreadsheet program, but this might help you.
Regards,
A.J.Hi cpitcher,
The VSG operates on USB 2.0. Fortunately USB 3.0 is backwards compatible so you are able to connect the VSG with supplied cable to a USB 2.0 or USB 3.0 port on your PC and everything will work.
If you have any further questions, let me know.
Regards,
A.J.Hello zhubajei,
I’m assuming you are targeting the same architecture on both PCs? If you are using Labview 32-bit on one PC and 64-bit on the other, that might be an issue. The error message you have received, “SH_API.dll not found” is a big red flag. This message has to be resolved first. It is possible the Labview configuration has changed on the tablet PC and Labview is looking for the DLL in a different location. (i.e. Different path variable, typos in your path?) My guess is that if you resolve this error, it will work as expected. If both PCs are running a full Windows 10 OS, there should not be any reason one would work and the other wouldn’t.
Regards,
A.J.Hi Rob,
Thanks for the follow up. With the 4FSK addition to the Spike software you should be able to analyze C4FM signals. My knowledge is cursory, forgive me if I am incorrect, but the C4FM spec is a 4FSK signal with 4.8k symbol rate, 1.8k deviation and root raised cosine filter. Our software is capable of measuring this signal. With our software you should be able to measure modulation fidelity, frequency offset, channel power, and ACPR. What other types of measurements are relevant to you for P25?
Regards,
A.J.Hello dwc,
The msvcp110.dll file is part of the Visual Studio 2012 redistributable files which can either be downloaded here http://www.microsoft.com/en-us/download/details.aspx?id=30679 or are part of the Visual Studio 2012 install. If you do not use Visual Studio 2012 you will still need to download these to program to the API. We have 32 and 64 bit versions of the API, so you could download both x86 and x64 versions of the redistributable for your PC. We used Visual Studio 2012 to develop the API which is why you are seeing this.
Regards,
A.J.Hi dwc,
If you decide to attempt programming the device, we have an API manual here, https://signalhound.com/sigdownloads/SA44B/SA-API-Manual.pdf. There is a code example in the appendix called “Sweep Mode” that shows you how to setup a sweep. This functionality could be performed in a loop to achieve the desired sweep. The labview examples are wrappers around the C functions, so learning the C functions would be beneficial if you decide to automate through Labview. You may contact me at aj at signalhound dot com if you have any programming related questions.
Regards,
A.J.Hi dwc,
This is a hard limitation of the device. Depending on your needs and skills, there might be ways to automate it. The device has a programming interface, if you are good with C programming and it would save you a lot of time, you could programmatically sweep the 1MHz to 10MHz span in 200kHz steps. Or, in the Spike software, you could set the frequency step to 200kHz and use the arrow keys next to the center frequency entry to quickly step through your span.
We apologize for the inconvenience.
Hello Saira,
Unfortunately this is not possible. There is no user accessible non-volatile memory on the VSG25A. The device can only be driven by our software and API. If it helps, in the software you can save presets, allowing you to quickly recover previous settings. You can also control the device in your own software by utilizing the C programming API.
Let me know if you have any further questions.
Regards,
A.J.Hi Rick,
What you are describing sounds like faulty hardware, (bad RF attenuator/RF input/etc.) Please contact us by phone at 1-800-260-TEST or email support@signalhound.com and we can discuss it further and discuss possible options for repair if we determine it is necessary.
Regards,
A.J.Hello Mike,
Can you try attenuating the input to ensure you are not in compression? Spike also sets the attenuator and pre-amp automatically based on reference level. With your ref offset active, set the reference level to +40 to see if this affects the measurement. I am concerned that the signal is possible being compressed in the Spike software.
Having said that…
I performed a similar measurement on both the Spike software and version 2.18. I was able to get similar results on both pieces of software. I have attached the measurements. In this case, I used a signal generator to create a wideband signal with an output power of -40dBm. Seeing a channel power output reading of -40dBm on both software versions lets me know I have configured the software correctly. If you have a generator, can you try a similar test?
Regards,
A.J.Hi Mike,
For the Spike software, to get comparable measurements, ensure video units are set to power, detector is set to average, and disable spur reject in the settings file menu. With these settings, you should see similar readings. For a wide band signal like this, ultimately, you will want to compare channel power readout.
Let me know if you have follow up questions.
Regards,
A.J.Hello Phil,
It may not be desirable, but we do have an older version of our software on the SA44/SA124 downloads page. It is version 2.18 of our software. It is not Spike but an older software package. This software does not have any GPU requirements and should be able to work on your PC. It’s on this page https://signalhound.com/support/downloads/sa44b-sa124b-downloads/ under the Legacy Software section.
I apologize for the inconvenience. If this is a new device and you do not have another computer to use the device on, please contact me at aj@signalhound.com.
Regards,
A.J.Hello Phil,
Based on the image you provided, it is the case that the PC does not look to have the necessary graphics support needed to run the software. The tell-tale sign is the solid white blank screen, denoting the graphics driver was unable to render the graticule. It is still possible that updating the graphics driver will resolve the issue. I found the driver downloads page here http://support.hp.com/us-en/drivers/selfservice/Compaq-Presario-CQ60-Notebook-PC-series/3944778/model/3979078#Z7_3054ICK0KGTE30AQO5O3KA30R1
On the page, under the “Graphics-Drivers” tab, try installing the Mobile Intel 4 Series Express Chipset Family Graphics Driver. There is another graphics driver on this page, if you believe you have this GPU, you can install that one instead. If this driver does not resolve the issue, then I do not believe Spike will be able to run on this system.Let me know if this resolves the issue.
Regards,
A.J.Hello Jose,
Email me at aj@signalhound.com. I can send you a Firmware update for your SA124A so that it will be compatible with the Spike software.
Regards,
A.J.