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Hello Mehran,
Thank you for the feedback. Can you clarify, is the monitoring section you are referring to the waterfall/spectrogram plot, or the interference hunting measurement mode? Can you provide any other sort of information regarding these features (pictures/manuals/etc). I want to ensure I understand the functionality you are looking for.
Regards,
AndrewIt looks like the channelizer only saves 8 channels instead of the expected 9. (Look at the sweep size to verify). Might be a rounding issue. I can look into getting a fix for this next release. Otherwise it does look like it is properly calculating your channel powers. It is still usable but will contain 1 less channel. You might have to increase your span to include all the channels for now. Also, note, the start/stop/center frequencies displayed during playback are the settings at the time of capture. You will want to use the marker readout to confirm the channel frequency.
Thanks for the feedback Miran,
AndrewThis is a nice feature Miran. We will definitely consider this for future software updates. I think this would be very helpful. Thank you for providing your feedback and suggestions, it is very appreciated.
Regards,
AndrewHello Miran,
You are talking about a relative frequency limit line? This is a good idea, but unfortunately we don’t have any implementation of this yet. I appreciate the feedback.
Regards
Hello Volker,
Did you try making the limit more like a box rather than a Spike like I suggested in my earlier response? Since your spike is smaller than 1 RBW the limit test point is being interpolated between the high point and adjacent low points. Unless the frequency bin happens to fall exactly on your high limit line point, it will interpolate somewhere along the steep limit line. This latest version is now drawing what is being tested against so there is no confusion, (the last version improperly drew the limit line as entered rather than the actual interpolated test points)
Ultimately I think this spike in the limit line approach to check for a CW is not ideal with how we implements limit lines and it looks like you had a perfect setup back in 3.1.11 because I can’t even reproduce your original image using the original limit line you provided. I think going towards a box/square shape and being mindful of your RBW will solve this problem long term.
Regards,
AndrewHi Mike,
The bulkhead connector is from Centric RF, part number C3614. It is considered a precision type-N connector. Particularly good VSWR. Data sheet link below. It is spec’d to 18GHz and in our tests fine up to 20GHz. The main reason for using the type-N was due to customer feedback, mainly revolving around robustness, rigidity, and prevalence in labs.
http://centricrf.com/content/pdf/C3614.pdf
Let us know if you have additional questions.
RegardsHi Seth,
What I think happens, is we use older OpenGL features to try to remain as compatible as possible across many systems. It appears some combinations of PC/drivers have issues with these older features. Our use of OpenGL is very minimal and I haven’t personally had the ability to debug on a system that experiences the issue. There are certain models that see it more than others, the X1 carbon is one of those models. It almost is always resolved with drivers from Intel rather than custom ones from the PC manufacturers.
I think the Win10 upgrade is a possible solution as it might give you access to the newer drivers which might resolve the incompatibility.
Regards
You could try the the graphics driver direct from Intel for this processor. Link is below (Note the CPU model at the top of the page) The Intel one looks to be a few years newer than the version you listed. (Hard to find exact dates) On occasion I have seen incompatibilities with vendor supplied graphics drivers vs. the Intel ones.
Hi Miran,
I’m not sure of the limitation. You can determine the COM port number of a device in the device manager.
Regards
It doesn’t look like your GSV sentence contains the SNR value, so it will stay empty.
Also I used this sentence format for the GGA string.
http://aprs.gids.nl/nmea/#gga
It looks like your message contains the data when it is emitted. Is it possible it is not emitting the GGA sentence in it’s current configuration?Miran,
If you are seeing the “Unable to Connect GPS” then this is not an issue with the NMEA data, it is an issue with attempting to open a file handle with the GPS. We use the CreateFile() function to open the GPS with a fileName of “COM#” where # is the COM port number you provided. Can you think of a reason why the GPS would be unable to open this way? Is it being interfaced in another application?
To answer your question, we only look at the RMC, GSV, and GGA sentences, but we only require the RMC to be present, if the others aren’t present then we ignore those values, but these sentences are only going to be looked at if the GPS is successfully connected, which it doesn’t sound like it is.
Regards
Here is an RMC string from our shop GPS. If I match it successfully (as per my previous post) I only look for the first 7 comma separated values, and ignore the rest.
$GPRMC,174641.000,A,4552.763046,N,12235.011607,W,0.011,142.26,210318,,,A*47
Miran,
Are you seeing the “CommErr” message in the Spike application?
If you haven’t already, verify the baud rate is correct.
It looks like after a few seconds, only the RMC string is being transmitted? It only transmits the other NMEA sentences on the first second? I believe in my code I pattern match everything between the string “RMC” and a newline, which means if the RMC sentence was the only sentence in the message it wouldn’t parse properly. I will need to account for this case for the next release.
Regards,
AndrewYou can change the length of the IQ capture waveform by simply changing how many IQ samples you request from the GetIQ functions. Since you know the sample rate of the device for the given acquisition, you can determine the length of the capture you need with the following equations.
sampleRate = 486111.111 / decimation;
timePerSample = 1.0 / sampleRate;
desiredSamples = desiredCaptureTime / timePerSample;I’m hoping for later this week or early next week on the Spike release. Thank you for your patience.
Regards
Hi Mike,
You are correct about the tuning speed and step size.
You can find the DANL specs here,
https://signalhound.com/download/sm200a-data-sheet/
The RBW will add 10*log10(RBW) dB to the noise floor.
But, sometimes a picture can be instructive.I attached an image of the device configured for the 1THz sweep speed. You can see the device sweeping a 20GHz span in 17.257ms with a 30kHz RBW and a reference level of -20dBm which will configure the receiver for maximum sensitivity. If you increase the reference level the noise floor will come up in 5dB steps.
Let us know if you have additional questions.
Regards,
AndrewHello Bindinir,
Thank you for sharing this picture. I was able to reproduce this issue without the DC block, (which isn’t required). It looks like a bug with our software at this very specific setup. If you change your stop frequency to 90MHz or 110MHz I noticed it no longer occurs and sweeps normally. I will explore this more. In the meantime are you able to change the stop frequency to one of these other values and continue use? If you encounter other issues you can let me know here or email me directly at aj at signalhound dot com. I can try to fix these before the next release.
Regards,
AndrewHello vanderbasaran,
If you are interested in the option 10, contact justin at signalhound dot com. He can give you pricing information and set you up with an RMA to get the option applied to your unit. If you haven’t purchased your unit yet, you can order through sales at signalhound dot com, and be sure to mention you want the option 10.
Regards,
AndrewI would expect this functionality within the next 6 months.
Regards,
AndrewHello Vanderbasaran,
At this point and time there is no way to utilize the FPGA resources for your own development. We have discussed this as a possibility but have no plans to implement this for now.
Regards,
Andrew