Hello Randy,

Have you taken a look at the IQ examples we provide in the C programming language? They are freely available in the API download folder. These examples will show you all the functions required to configure IQ acquisition. I suggest getting the functionality to work in C before moving to Labview.

The download link for the API files is on the downloads page at,
https://signalhound.com/support/product-downloads/sa44b-sa124b-downloads/

The download also includes the API manual which will help with any questions you have while looking over the API examples.

Regards,
A.J.

Hello Randy,

I apologize, we do not have any examples for IQ acquisition in Labview. We only have the sweep example found in the API download folder and there are some sweep examples developed by customers on our forums.

Regards,
A.J.

Hi Tom,

If you need time stamping from a GPS, you can accomplish this but will need to utilize the C programming interface to accomplish this. Our desktop software does not expose this functionality. If it is interesting to you, a future update to our software will allow long IQ recordings with system time stamping (non GPS). I would expect this in the coming weeks to months.

Using an external GPS and our programming interface, you can expect time stamping with a resolution of around 50ns at the highest sample rates (40MS/s IQ). There is a code example of performing this on page 45 of our programming manual, which you can find linked here,
https://signalhound.com/sigdownloads/BB60C/BB60-API-Manual.pdf
It uses a deprecated function (bbFetchRaw) which has been replaced with bbGetIQ, but otherwise would remain the same if you decided to implement this.

If you have any additional questions let me know.

Regards,
A.J.

Hi Phil,

Yes, this is all within Spike. The signal symbol rate can be set up to 12.5MS/s. All views and measurements that you have access to with the SA will be available with BB60C.

I attached an image showing this setup using a vector signal generator at my desk. Notice the symbol rate entry.

If you have additional questions let me know.

Regards,
A.J.

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Hi Phil,

Currently the maximum symbol rate the BB60C is capable of demodulating is 12.5MS/s. I would expect the BB60C would have no issue demodulating your BPSK signal.

If you have additional questions, let us know.

Regards,
A.J.

Hi Jared,

I apologize if you already knew this, but you didn’t mention it in your message. The frequency up/down arrows adjust the center frequency by the “step” amount, which you can enter a few boxes down.

If you continue to have connection issues, email Justin at justin at signalhound dot com and point him to this thread as well. The SA44B disconnecting in this way is rare, if general troubleshooting does not solve the problem we might suggest an RMA (for us to reproduce the issue in our shop), or ship you a new cable. If you are able to reproduce the issue on another PC, we would be interested to know.

Regards,
A.J.

Sadak,

There is unfortunately no way to directly pre-calculate beforehand the bin size because we create the window function at the time of saInitiate(). Other analyzers might use fixed windows and zero-padding which would allow you to pre-calculate the bin size beforehand. Depending on the RBW the window might affect the bin size between a factor of 3-6. (ie The bin size is roughly between 3 and 6 times smaller than the RBW), but again, there is no way to fully pre-calculate this value. This is why we provide the bin size with the start frequency, so you can calculate the frequency of any given bin and also target the frequency bin you are interested in with a small amount of arithmetic.

That said… if you require a sweep with a specific bin size spacing, you could convert the sweep the API returns by re-sampling the sweep at the frequencies you want. A very simple algorithm for this would be to simply select the closest bin to the frequency you desire and use this amplitude for your new bin. You would not want to ‘resample’ by a large factor, ideally you are ‘resampling’ by some small fraction to line up the bins on some frequency that is convenient for you. The flattop window would ensure that your peaks would remain. Certain measurements such as channel power might be affected but probably by negligible amounts.

Regards,
A.J.

Hi Sadak,

The bin size is a relationship between RBW and the window function used. For most of our processing, we use a variable flat-top window to achieve the desired RBW.

The saBandwidthClamped warning will get returned during saInitiate if the RBW had to be changed to fit within the limitations of the device.

We have a list of the RBW limitations in the user manual here, under section 2.3.1, many of them are related to center frequency and span. This manual is for the SA44B but applies to the SA124 as well.

https://signalhound.com/sigdownloads/SA44B/SA44B-User-Manual.pdf

If you have follow up questions, let me know.

Regards,
A.J.

Hi Andy,

We can set you up with a warranty adjustment since the mixer replacement was recent.

Contact me at aj at signalhound dot com.

Regards,
A.J.

Hi Jared,

Regarding the connection issues. What is your current PC power options setting? (Press Windows Key -> Type “Power Options”) We do recommend high performance and for many customers with similar issues, changing this resolves the issue.

As for your measurement requirement, I think the additions to zero-span will be able to satisfy your requirement. 10 second triggerd captures will be possible as well as playing back the file and triggering on events within the capture. I don’t have a time frame on this yet, but it should be in the next release.

Regards,
A.J.

Hi Jared,

At this point and time we do not have plans to implement this. I have made a note of your request as it may be something we decide to pursue in the future.

Regards,
A.J.

Hi Jared,

We have talked about updating the 2D waterfall plots to include more functional measurements. We are aware of the limitations of this plot in its current implementation. There is no time frame on this yet.

You are looking for a long triggered capture? I am currently expanding the functionality of zero-span. I am adding more flexible/adjustable plots, increased capture times, and long term IQ recording/playback through the Spike software. If you could detail your requirements a bit more, I might be able to determine if this functionality will address your needs.

What kind of connection issues are you experiencing? Intermittent disconnects? This is for an SA44B or SA124B?

Regards,
A.J.

Alfred,

Contact us directly at justin (at) signalhound (dot) com. We will be able to more quickly assist you via email.

Let us know the CPU make/model and any troubleshooting steps you have taken up to this point.

Regards,
A.J.

Hi Joeqsmith,

I apologize for the issues you have been having. Because you are seeing issues consistently across the software, I think we need to start by determining if there is some underlying incompatibility/driver/etc. we need to address.

For quicker responses and support you can email me directly at aj at signalhound dot com.

Start by sending me any information you can on your current PC. I will be interested in information such as, is it a laptop/desktop, manufacturer, model, CPU model number, GPU model number (if you have a dedicated card), 64-bit/32-bit operating system, and anything else you think would be relevant or that might pertain to your setup.

Feel free to send me pictures of any error messages you receive with a picture of the Spike software at the time. It might help narrow down exactly where the issue is occurring.

Have you successfully used the unit on a different PC, or is this the first time using the BB60C?

I look forward to your response.

Regards,
A.J.

Hi Sam,

The process is similar for the SA44B except there are a few things you need to be aware of.

You will need to disable the software spur rejection to be able to make accurate channel power measurements. This can be disabled in the “Settings” menu. The SA44B enables this setting by default.

Average detector and Power video units should still be set.

If the traces are stored in dBm units, then steps 3,4,5 will apply.

Since I have posted the steps above, I have a simplified approach to approximating the window bandwidth. This will be possible as well with the BBR files as well.

The window bandwidth can be approximated as
WB = rbw / bin_size(freq between each spectrum bin)
Both RBW and bin size are stored in the BBR file.

I will attach two files that we use as examples for customers.
One is for calculating channel power, the other is for parsing BBR files.

Let me know if you have additional questions or need clarifications.

Regards,
A.J.

[Edited to fix upload errors]

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Hi Mike,

We very recently took a look at 8VSB and determined it would require additional work beyond our initial estimate. Additional algorithms would need to be developed to properly demodulate 8VSB. I do not think we have immediate plans to develop this as we are currently working on other projects but I will make a note that you are looking for this functionality. This is very helpful for us when we decide what to work on in the future. Viewing 8VSB would also require a BB60C as it is our only receiver with the necessary bandwidth to capture the signal.

The SA44 has only a few limitations compared to the SA44B. Most notable,
– the SA44B has a preamp
– improved spurious responses with the SA44B
– and sweeps speeds and available RBWs between spans of 200kHz and 200MHz. The SA44B will have faster sweep times and allow smaller RBWs in this range of spans.

If you have additional questions, let us know.

Regards,
A.J.

Hello Sajdenman,

It appears to currently be working this way. I apologize for the inconvenience. I will see if I can fix this for the next release.

Regards,
A.J.

Hi Sajdenman,

Unfortunately scaling the y-axis is not currently possible. This is something we are looking to address in the near future. Based on your post, I believe you have properly described its current behavior. I apologize for the inconvenience.

Regards,
A.J.

Hello JosuePareja,

The VSG is not directly able to be controlled in Matlab. You will need to write a small interface between Matlab and our C interface to the VSG to get this to work. The API files are located in the installation directory on your PC, which is probably in the folder C:\ProgramFiles(x86)\SignalHound\VSG25\api. Take a look at the loadlibrary and calllib functions in Matlab for calling into a C DLL on Windows.

If you wish to use Matlab to generate IQ data that you can then load via ARB CSV files, you can do this also. You will need to generate the IQ data in Matlab and then create a compatible CSV file that can be read into our software. You can find several examples of CSV files in the installation directory as well, in the arb_examples folder. Take a look at the “BPSKUnfiltered” or “Chirp” examples for basic examples with text explanations. You will need to adhere to the format exactly otherwise the software will be unable to read the file.

Let us know if you have further questions.

Regards,
A.J.

Hi Frank,

Yes, all of our spectrum analyzers have internal references. You do not need to provide an external reference unless you desire. Also, when you select “Internal Out” in the file menu, this does mean that you are attempting to output the internal reference on the BNC port, which is not supported for the SA44B.

As for your disconnection issues. Is this a recent issue, or has it always been like this? Basic troubleshooting steps might involve
1) Trying a different USB port on the PC.
2) Checking the USB connector for debris.
3) Swapping USB cables
4) Stopping background processes that might be consuming large amounts of resources.
5) Setting your power option to “High Performance” via the Control Panel->Power Options menu. This is a common solution to random device disconnects.
6) Disabling any anti-virus software.

I look forward to your response.

Regards,
A.J.

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