Hello Patrick,

Good questions. To start, no, the bbInitiate function does not need to be called for each data acquisition. If you use the initiate function to configure a particular sweep, you may continue to acquire sweeps until you call the bbInitiate function again. bbInitiate must be called to change configuration though. If you are sweeping, the bbInitiate function is nearly instantaneous (no hardware involvement is required). Most of the work done is pre-allocating memory and processing classes. So even if you need to rapidly change sweep parameters this will appear instantaneous. If you are streaming I/Q data, the initiate function takes about 17ms using BB60C firmware version 6, and ~750ms using firmware version 5 or less. The long delay for firmware version 5 is due to inefficiencies in shutting down the data stream to the PC. We have very recently corrected this and released it as a firmware update (ver 6). New units will ship with this, and old units can upgrade. You must be using the latest API to get the low I/Q switch speeds. (API version 3.0.6)

Our spectrum analyzer software uses the same exact API we provide users.

Regarding GNURadio, currently we do not have support for it, nor do we plans for building the necessary interface. We would love to, but we have limited programming resources.

Regards,
A.J.

I can’t speak for the RSA306, but the BB60C has sweep support (step, acquire, step, etc) at the firmware level. Sweep speed on the BB60C is truly hardware limited.

Regards,
A.J.

Hello Cyounkins,

I apologize, this appears to be a limitation that was arbitrarily set. If you email me I can send you a version of the software which has this limitation removed. Email me at aj@signalhound.com.

Make sure the latest version is installed (3.0.11) and I will send you a new file for the fix. Let me know if you install the 32-bit or 64-bit version.

Regards,
A.J.

Hey Jyaron,

There is no immediate plans to include this type of functionality, but in the near future we will be addressing a number of EMI/EMC type measurements and peak tables is one we will likely be adding. This looks to be a very similar type functionality.

Regards,
A.J.

Hello Mark,

Email justin@teplus.com and explain that you want the TG124A API for Windows. He will send you a small C API for it. We do not provide the source code, only the C interface.

Regards,
A.J.

Hi Mark,

I do not believe we have a way to control the TG124A on Linux. Our TG control app is on Windows only. I apologize for the inconvenience.

Regards,
A.J.

Hello Brainliterral,

Someone here may be able to provide you with some materials to get you going. Signal Hound does not currently have any documentation on interfacing our APIs in Matlab. You will need to learn the API enough to make function calls to it in Matlab. You can find our API manuals in the api/ folder in the installation directory. Matlab provides documentation for calling functions in a DLL.

http://www.mathworks.com/help/matlab/using-c-shared-library-functions-in-matlab-.html

Regards

Hello David,

Please email me at aj@signalhound.com.
Send me the source file you are working with, I would be happy to look it over. It sounds like you are doing everything correctly, but I would like to verify it.

Regards,
A.J.

Hello David,

What is the frequency of the bin you are sampling? You can determine the frequency of any point in the resulting sweep with the formula

f = start + index * bin_size;

Replace index with sweepLen/2 for your example. The center point is not necessarily the center frequency of the sweep. Use the equation to get the index of the frequency you desire.

Also, without knowing your specific application, you will likely want to sample the returned ‘max’ array. Depending on RBW and VBW they are not necessarily the same when the SA_MIN_MAX detector is selected.

Let me know if this does not resolve the discrepancy you are seeing.

Regards,
A.J.

Hey John,

Broadcast masks were one of the features that has yet to make it into the Spike software. It is a feature we want to add back in at some point though. I did ensure that Spike can be installed side-by-side with the old software (2.18) in the event you need to use any features that are not in Spike yet. I do apologize for the inconvenience.

I do like the idea of creating a CSV that can dynamically create the limit lines. I can’t offer that at this moment though, but I can point you to the documentation that we used to create the AM/FM masks, http://www.nrscstandards.org/DocumentArchive/NRSC-G201.pdf.

Regards,
A.J.

Hi Tom,

The 5 MHz RBW for SA44B is not something that has made it over to the Spike software at this point. It is something we want to add back in eventually. The old software (2.18) can be installed side-by-side with Spike if you need to use this functionality for the time being. I apologize for the inconvenience.

Regards,
A.J.

Hello Catalin,

Thank you for bringing this up. This is a limitation of the design, and something we have been wanting to address. We spent some time this morning revisiting this and we may have a future solution. I will try to keep you up to date, this is something that we could maybe address in the coming weeks. Email me at aj@signalhound.com so I have your email, and I can notify you when/if we have a solution.

Regards,
A.J.

Hello Sarah,

I do not have enough familiarity with Labview to resolve this I believe. My co-worker is the one familiar with Labview. He is on vacation and will be back next week. Email justin@teplus.com and he will get back to you.

Some notes: The function should take a pointer to an array very similarly to the get sweep functions. Labview might treat integer arrays differently. You can see this function in action if you start the Spike software with no devices attached, then plug in both devices and go to the File -> Connect menu. You should see a list of your devices which is generated with the GetSerialNumberList function. The serial numbers will not appear if the devices have been opened with the saOpenDevice function. If either parameter is null then the function will return early as well.

Regards,
A.J.

Hi crcarle,

Yes, we are aware of the scaling issues and we will address them in a future update. We do not have a time frame yet on when that will be though. I apologize for the inconvenience.

Regards,
A.J.

Hello Juan,

I attached an image of the device in the Spike software exhibiting the same shape as your software. I used 1 dB per div while your plot was 0.2 dB per div. The shape you are seeing is the shape of the IF band, the result of any filters and the RF path. The RF gain/attenuation is going to affect this shape as well as the frequency. Different start/stop frequencies will change the RF path of the input.

I hope this clarifies and validates what you are seeing.

Regards,
A.J.

Attachments:

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Hello crcarle,

Can you post an image of this? Do you have text/icon scaling active? Our software text does not scale appropriately when the Windows text/icon scaling is active (more than 100%).

Regards,
A.J.

Thank you for bringing this up. The mouse pointer readout should only be used to make very quick measurements as the pointer has only 1 pixel resolution and does not map very well to points in the sweep. Use markers to make precise measurements. After you click on the sweep to place the marker, you can move the marker using the arrow keys.

I hope I addressed the concern you raised.

Regards,
A.J.

Hello bbowar,

We use custom size flattop windows to achieve our RBWs, which means the noise bandwidth will be dependent on the current RBW. You will need to calculate the noise bandwidth of our window function like this.

// rbw = current resolution bandwidth
// log2 = log base 2
// pow2 = 2 ^ value
double min_bin_sz = rbw / 3.2;
double min_fft = 486111.111 / min_bin_sz;
int order = (int)ceil(log2(min_fft));
int fft_size = pow2(order);
double noise_bw = (rbw * (double)fft_size) / 486111.111;

This could probably be simplified a bit more as well.

Just to verify, here is how we calculate channel power in our software to compare against.

1) Set Average Detector and Power video units
2) Get sweep
3) Convert frequency range to power units (W)
4) Sum frequency range of interest in power units
5) Divide sum by the window bandwidth (or noise bandwidth) as calculated above.

Let me know if you have any further questions
Regards,
A.J.

Hello Sarah.b,

Just to clarify you are calling saInitiate() again after changing the reference level? This is required anytime you want to update any pending configuration changes.

Regards,
A.J.

Hello davorin,

Yes it is safe to make the measurement you desire. You will want the setup to look like this.

[12V DC] -> [DC Blocker] -> [Attenuator] -> [SA44B]

You can also use our Auburn probe for probing the circuit itself for the noise. It has a built in DC block and 20 dB attenuator.

Regards,
A.J.

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