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Hello Feng,
You did not state whether you are using the API or using our supplied software. If you are using our software then you can setup video triggers in zero-span mode using the control panel. If you are using the API and retrieving IQ data from the device directly then video triggering is just a function of checking each IQ sample for you trigger level.
If this does not answer your question, please try to restate your questions.
Regards,
A.J.Hello Mark,
I can explain what you are seeing, and clarify the difference in behavior between the old software and new software.
As you know, a frequency bin in a sweep rarely lines up nicely on an even number like 10MHz. When you enter a marker frequency like 10MHz the closest frequency bin has to be used, and it might correlate to a frequency like 9.999037MHz. The old software simply printed the frequency you entered even though it was using the frequency bin at 9.999037MHz while the new software will simply show you the frequency of the bin used.
Ultimately both versions of the software use the same frequency bin to report the amplitude but the old software shows you the frequency you entered and the new software shows you the actual frequency of the marker.
Let me know if you have further questions.
Regards,
A.J.Jared,
In hindsight that would have been a better idea.
Regards,
A.J.Hello Marholt,
That is correct, CPU speed affects sweep speed up to a point. That point is when the time to acquire data from the device is greater than the time to process it. For most sweeps, the processing can happen in parallel with the data acquisition. There are many factors at play here (single vs. multithreaded processors, RBW, VBW) and so it is impossible to give you a single number that would meet your needs. The sweep times you see on the 3.3/2.7 GHz processors are almost certainly the fastest those sweeps can perform.
Regards,
A.J.Hello Filippo,
We do have an example. If you go into the bb_series folder we have a fully fleshed out API in the csharp folder for our BB60 API. The BB60 API is very similar to the SA44/124 API so it will be mostly cut and paste.
The mechanism by which this is performed is commonly referred to by many names, most notably as PInvoke, Interop, or marshalling. These are the mechanism by which a C# program can call a C function in a DLL on Windows. Searching the internet for these terms will return many examples of doing this.
Regards,
A.J.Hello Jason,
The preset files are located at
C:\Users\YourUserName\AppData\Roaming\SignalHound\
AppData is a hidden folder by default on Windows systems
They are named “Preset[0-8].ini” and they correspond to Presets [1-9] in the software.
You can place them on a different computer in the same directory and they should work. Each preset is only compatible with one type of device, e.g. a preset saved with an SA124 cannot be loaded for an SA44.Regards,
A.J.Hello Feng,
Video and External(BB60 only) triggering is available in Zero-Span mode. You can configure the triggers on the control panel after entering Zero-Span mode. In the API no triggering is performed directly, but the location of external triggers are returned when the API is configured correctly. You can see the API manual to learn more about setting up external triggers. https://signalhound.com/sigdownloads/BB60C/BB60-API-Manual.pdf
Regards,
A.J.Hey Jared,
Thanks for the feedback. The trace export format is mentioned very briefly in the user manual on page 9.
The format for the columns is
Freq in Mhz, Min Amplitude, Max Amplitude.I hope this clarifies why you are seeing what appears to be multiple traces.
Regards,
A.J.Hello Feng,
The software is open source, so the .bbr format is exposed if you want to try to extract information from the file.
The two files of significance would be
https://github.com/SignalHound/BBApp/blob/master/BBApp/src/model/playback_toolbar.h
https://github.com/SignalHound/BBApp/blob/master/BBApp/src/model/playback_toolbar.cppThe format is a bit simplistic, which does make it simple to parse.
It starts with a header, defined in playback_toolbar.h.
Then there are ‘header::sweep_count’ traces which are laid sequentially out as– (Header 1 time only)
– 64 bit integer, (standard ms from epoch time, when the sweep was captured)
– header::trace_len 32-bit floats representing the “min” trace
– header::trace_len 32-bit floats representing the “max” trace
– (Repeat last 3 lines until eof)Everything is saved as binary, so fread will work great.
Let us know if you have any other questions.Hello Bongo,
Thank you for confirming this. Spike requires a minimum of OpenGL 2.0 to run. I apologize for the inconvenience.
Regards,
A.J.Hello Bongo,
The laptop you specified may not have the graphics capabilities required to run the Spike software. I was unable to find any information regarding the graphics capabilities of your laptop. You could try installing the latest video drivers from your manufacturer and making sure Windows updates is fully updated to see if that resolves the issue.
The OpenGL message you are seeing is almost certainly the result of uninstalling the video driver.
Regards,
A.J.Hello Jared,
Thank you very much for your feedback. There are a couple of points I can address now which might be of help to you.
3) BUG – RBW isn’t entirely settable. In some EMC related ranges I have to settle for 100kHz or 10kHz instead of 120kHz and 9kHz respectively.
Limitations of the device (the SA44/SA124) prevent us from being able to set the RBW to 120kHz. Even our older software was unable to do this, but 9kHz should be available to you at any time during operation.4) FEATURE – Whilst I only had a brief look at the zero span, AM/FM demodulation, and receiver/channel power etc, the FM demodulation on our local radio stations is much improved and the zero span would give me some useful information, however it would be nice to set this such that it behaves kind of like an oscilloscope (i.e. edge/level triggering and position so I can check duty cycle and Tx power).
In Zero-Span mode, on the control panel you can set a video/external trigger to perform the edge level triggering. Position was added in a subsequent release, so if you download the latest version, you can configure a trigger level and position.22) FEATURE – Could you get your website guys to put up a changelog file/page or include it in the install files?
Otherwise, it’s a bit vague as to what’s changed between revisions.
I will work on getting the change log on the downloads page. Currently it can be found in the installation folder after you install the software.Thanks again for the feedback.
Regards,
A.J.Hello Cliff,
We have the exact same Dell Venue model in our shop and we have experienced this problem. We solved this by using one of our SA124 y-cables and only using the data portion of the y. We will ship you a y-cable if you do not have one so you can use the device with your Dell tablet. Call me at 1-800-260-TEST Ext. 2 from 8-3 PST and I can set you up with a free cable.
Regards,
A.J.Hello Roger,
Thank you for calling in. Hopefully we were able to fully answer your questions. If you need anything further please let us know.
Regards,
A.J.Hello Marholt,
The Windows libraries have received a major update over the last couple of weeks. You can get the libraries by downloading the Spike software package here. signalhound.flywheelsites.com/spike You can find the library file and API manual in the api folder in the application directory after installation. The API does not provide channel power measurements directly but returns sweeps on which you can perform your channel power measurements.
Regards,
A.J.Hello Garry,
Thank you for the feedback. We are aware of the issue with Zero-Span. We are working on a solution for the next release and will release a notice on the forum when we have something for customers to try. I apologize for the inconvenience.
The calibration data is now stored at
C:\ProgramData\SignalHound\cal_files
ProgramData is a hidden folder and is the de-facto storage location for these types of files on Windows. By storing them here, the software no longer needs to be run as Administrator. Our hope is that you should no longer have to worry about the management of those files.Regards,
A.J. February 23, 2015 at 1:27 pm in reply to: USB-SA44B New API 3.0 (sa_api.dll) Resolution Band Width Settings Hello Roger,
Good question. In a spectrum analyzer, resolution bandwidth is typically defined by the 3dB bandwidth. This is the width of a signal (CW) measured 3dB down from the peak on either side. This is the definition we use.
The reason the bin size is not equivalent to the RBW is due to the use of window functions. If you are not familiar with window functions see here. http://en.wikipedia.org/wiki/Window_function Most windows functions spread the spectral energy across multiple bins, which is commonly referred to as the window bandwidth, or noise bandwidth, or B. Flat-top windows have a higher bandwidth than most, usually B > 3. We use custom flat-top windows to achieve a higher amplitude accuracy, reduce spectral leakage, and maintain a high dynamic range.
You can directly calculate B using your example by the equation… 10 / 1.854 = B.
B will not be the same all the time, as we attempt to find the best B for any given setup.Let us know if you have any other questions.
Regards,
A.J.Hello Lisunov,
The TG44A is a companion product to the SA44B and they are meant to operate together. The tracking generator (TG) is simply a CW generator that has been designed to operate with the SA44B to function as a Scalar Network Analyzer. Our software exposes this functionality to the user when both devices are present. Both devices are needed if you want this functionality.
If you have any further questions please email support@signalhound.com
Regards,
A.J.Thank you for the heads up on the Linux API. I can look into it. Are you looking to stay on Linux or use Windows to take advantage of the new API updates?
Our Linux APIs (non-ARMs) required low-latency kernels and do not include any updates made over the last couple of years.
Regards,
A.J.Hello again Jacob,
Another question. Have you recently purchased this device or is this a device you have owned for awhile and are now seeing this behavior with the Spike software?
Regards