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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.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.Hello Paul,
The modulation depth for FSK is the ratio of the frequency deviation to modulation frequency. A more common term for it is modulation index.
e.g. If modulation depth is set to 0.5, then the frequency deviation will be 1/2 of the symbol rate frequency.
Regards,
A.J.Hi Paul,
Thank you for the feedback.
Currently through the standard software interface it is only possible to set a period with the ARB setup. This may not be practical for you unless you know how to generate your waveform though. With the ARB setup, you can select a period for your waveform up to 64k samples. So the period length would be limited by the sample rate. We have had another request for this functionality, so I believe we will be adding the period parameter to the standard modulation setup in the near future.
Regards,
A.J.Hello oogieoogieful,
Just to clarify, I though because you were using the SHAPISlowPlot.m file you would be using the and SA44/SA124. I am now under the impression that you have retrofitted it to call the BB60 API instead of the SA API. If you have done that and you have the latest version of the BB60 API then you should be able to simply use the 64-bit BB60 API with your code. We distribute both 32 and 64 bit API builds for then BB60 API. You can find it in typically at C:/ProgramFiles/SignalHound/Spike/api/x64
Regards,
A.J.Hi Gerry,
This does look like a potential issue with the unit. There are normally spurs in that frequency range but your unit is exhibiting higher than typical spurs.
Please call us at 1-800-260-TEST so we can issue an RMA and try to fix the unit.
Regards,
A.J.Hello oogieoogieful,
Someone else might be able to help you get things working, but our experience is that we have not had a customer be able to utilize our supplied 32-bit Matlab example on a 64-bit version of Matlab. We do not have a version of 64-bit Matlab in our shop and so have been unable to attempt to work through the incompatibilities. It does appear that one would have to go through quite a bit of effort to call a 32-bit DLL from 64-bit Matlab.
If you are interested, we have fully updated our SA device APIs. There are now 32 and 64 bit versions of the API that get installed when you download the latest version of our Spike spectrum analyzer software. http://www.signalhound.com/Spike. We recommend all new developers target these new APIs. They come with documentation as well to get you going. We do not currently provide Matlab interfaces to them, but if you are adept at C/Matlab programming you should be able to find enough information to call our 64-bit DLL from Matlab. The new APIs do have a different interface than the old ones, so there will be a learning curve which may not be acceptable if you are already familiar with the older APIs.
Let me know if you have any follow up questions.
Regards,
A.J.Hello Kirbi,
Depending on which sa_api version you are running, real-time functionality has changed recently. You will want to check out the programming manual for your version to find a full C example in the appendix for setting up real-time mode. This should help you set up Labview.
Regards,
A.J.Hello Michelv,
This was an issue for BB60As purchased before 9/13/2013. We have a firmware update to resolve this found on the downloads page https://signalhound.com/support/downloads/bb60c-bb60a-downloads/. Look for BB60A Firmware Update. Follow the instructions carefully and make sure you have a good USB connection before starting the update.
Regards,
A.J.Hello Richard,
This type of behavior is specifically the result of running our software in a virtual machine. We have had a number of users report this type of behavior running our products in a VM on Apple PCs. At this point and time we have not determined a possible solution to this problem, we can only suggest running the software on a Windows PC. An alternative (but untested) solution would be to run Windows native on the Apple PC using bootcamp or something similar. We have not tested this though, it may not solve the problem.
Let me know if you have any other questions. Thank you for the feedback.
Regards,
A.J.Hey Jared,
Thank you for clarifying your needs on the burst transmit. Currently the ARB functionality allows you to set a period value of up to 64k (pattern memory of 2k I/Q) which depending on pattern length can get you close to the duty cycle you need. This is only exposed through loading a custom ARB file though, so I think we would need to expose the period setting through the software/standard mods at some point to be truly useful.
At this point, the BB60C is only going to run on USB 3.0. The architecture is such that it requires a host PC to perform the majority of processing. The device itself has little resources to do the processing required to turn IF samples into sweeps (FFTs), or decimate, and this is what is needed to reduce throughput to the PC. Look for future products to address this.
A side note, the USB 3.0 hubs we use in shop are these http://www.amazon.com/Belkin-SuperSpeed-USB-4-Port-F4U058tt/dp/B009AR2MD2. They let us connect and run up to 8 BB60Cs at a time off a standard laptop.
Regards,
A.J.Hey Jared,
The only thing we have found to be consistent is direct connection to a PC with native (hardware on cpu) USB 3.0. We have had some luck with USB 3.0 hubs and PCI USB 3.0 cards, while others outright fail. I can’t comment on the Thinkpad hub unfortunately.
I asked Justin about the behavior you noted with the mod on/off button, and this appears to be the necessary setup when using the DDS on the VSG. You will see this on the frequency modulated signals such as FM/FSK. You will see another type of behavior for the ARB modulated signals like PSK/multi-tone, again, simply the necessary setup. We are assuming you are looking to achieve some sort of video trigger effect, especially with the request to transmit ‘n’ packets. This is definitely something we will consider on the next hardware revision if we can.
As always, I keep track of all feature requests, thank you for testing the VSG.
Regards,
A.J.Hello Paul,
Our software does include a waterfall display, but does not support the ability to zoom or adjust view regions. We provide the capability to record a series of sweeps and replay them in the software. The waterfall plot can be activated during this replay.
As for Labview support, we provide examples of how to interface our DLL programming interfaces, and some customers have provided sample labview drivers for our interfaces as well, one on the forums here https://signalhound.com/support/forums/topic/labview-drivers-for-sa44/. This might be enough to get you going in Labview.
Regards,
A.J.Hey Jared,
I can’t comment on the mod on/off note. Will get Justin to reply when we get back to the shop.
I can say FSK is on our roadmap. No timeframe yet, but very much something we want to do.
What kind of connection difficulties are you experiencing?
Regards,
A.J.