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Looking at the logic now. It does not appear to stop reading after a comm err. It continues to read the input and if it found the RMC sentence in a subsequent message it would update the dialog with the nav info found.
The Spike software does expect the RMC string to be sent in each update, and it does expect roughly a 1 second update rate. My COM reads have a 50ms readintervalTimeout, and a 2second total timeout. I read 2k bytes at a time in a loop. If you are using a low baud, like 9600, you might simply be trying to transmit too much data in this interval. Consider increasing your baud rate or decreasing your message size if you can.
If RMC messages were still coming in periodically, I would expect you to see it flip between valid and Comm Error.
Looking at the code here, it also looks like it will still save the last lat/lon it found. So even if it was flipping between valid data and comm err, the mapping mode should still be able to query the last valid value seen.
Andrew
The ‘V’ in the second field indicates “void” or that the data is invalid. You can see this too, as the fields after the ‘V’ should contain the lat/lon but they are empty.
Are you getting the “Comm Err” message? If yes, then it’s not even getting that far to see the ‘V’. The Comm Err indicates the software is not even seeing the “RMC” substring, which does indicate potentially the baud rates not matching or some other issue with the data. It looks like you can control the baud rate in the document you linked, you might try configuring different rates on the unit itself. Presumably you can also see the device listed under the COM ports in the device manager?
If you were able resolve the comm error, then the device would still report “Unlocked” with your current message shown and the lat/lon wouldn’t be available to the mapping measurements.
We used this USB GPS antenna (linked below) with success in our testing. It did involve some setup we can try to help you with if you go this route.
Andrew
Brian,
I’m assuming you are on Windows? The software is looking for the RMC NMEA sentence. Have you used something like tera term to verify the serial output of the GPS? What is the model number for your unit?
Andrew
The type 2 BB60C was a minor component change with no affect to the operation of the unit. You can determine if you have a BB60C-2 by connecting your unit to the PC and looking in the device manager under USB devices. It will show up as a “BB60C” for type 1 devices, and “BB60C-2” for type 2 devices.
If you are still unsure, you can contact our service department at service@signalhound.com with your serial number and we can look up your unit.
Andrew
DAtkins,
Thanks for the suggestion. I got it into the customer request log. We’ll consider how we can add this to our software.
Thanks!
Hi Volker,
Yes, we have been working on LTE measurements and hope to release them in Spike soon. Due to customer feedback we are also exploring 5G measurement support to be released simultaneously. Unfortunately we don’t have a set release date, but it does look like 2022 at this point.
If you have specific LTE/5G measurement requirements, please reach out to me at aj at signalhound dot com to let me know about them. I look forward to any feedback on this.
Andrew
Michael,
I will add your name to our contact list for the SM435B any any high freq gen we release. We will contact users closer to when the SM435B goes on sale.
Mneuman,
Our RF engineer Justin might be able to reply with a suggestion.
Andrew
Hi Michael,
We have discussed it, but there is nothing in the works yet.
Andrew
Please email aj at signalhound dot com and I can help you further. Please send me the following information.
1) What is the S/N of the unit?
2) Did you buy the unit new from us? How recent?
3) If the front end is damaged (such as a switch/atten) you may not see a signal. Is it possible the unit was damaged due to static or high input (> 20dB). Are you grounded when attaching your antennas?I look forward to your response.
Andrew
Are you able to upload a smaller picture? It rejected your picture based on file size.
Is this the first time you have used the device?
Do you have an antenna attached?
What signals are you expecting to receive?
Andrew
GSingh,
You could use PyVISA to control the VSG60 software using SCPI commands. You can read about our SCPI commands and see some examples in the SDK.
If you are using the API directly to control the instrument, you will need to generate your own complex I/Q waveform to output to the device. For a multi-tone signal, you could sum your complex sines/tones into an I/Q buffer to transmit. Just ensure that you scale the final result so that the peak magnitude of any given sample doesn’t exceed 1.0, and ideally, select a final buffer size that allows all of your complex sines to phase wrap nicely.
Unfortunately we don’t have any Python sample code for doing this. There are probably RF/DSP libraries that make it easy to generate complex sine waves with a given frequency.
Let us know if you have follow up questions.
Andrew
Miran,
Yes, you are correct in your understanding about the limitations of the Spike software.
Until we are able to add something to address this in the software, I would take a combined approach, setting the ref level offset to 40dB and then adjusting your path loss table by 40dB. Together you will get the same result with the ability to set the ref level to +60dBm. You should be able to save the path loss table with a preset for quick loading of this setup.
I will add this to our request log and determine the best approach to this.
Andrew
Hugh,
Did you change the monitor configuration recently? If you went from 2 monitors to 1 for instance, it might put the application where the second screen used to be (off screen)
Let’s try this. Close Spike and delete the file at this location.
C:\Users\YourUserName\AppData\Roaming\SignalHound\Layout.ini
Once deleted, restart Spike.
If you don’t see the AppData folder at first, it is a hidden folder, you will have to “Show hidden folders” in the file explorer settings menu.
Let me know if this resolves the problem.
Andrew
We do not have a block diagram that covers sweep/real-time mode signal processing. If you have a specific question about it, I can try to answer it for you.
Andrew
Michael,
Copied from the VSG60 users manual. This should clear things up. In this description, average power = average power of the I/Q samples, power = (i^2 + q^2)
Output Signal Average – When enabled, the signal generator output level will be adjusted to ensure the average signal power transmitted is equal to the output level selected. The average signal power is calculated after any I/Q scaling is applied. For example, if the waveform has an average power of -6dBFS (after scaling), and the output level is set to -20dBm, the output level is adjusted to -14dBm to ensure the average signal power output is -20dBm. The output level cannot be adjusted beyond +10dBm. For signals with long off durations, this should be disabled, as the average power of the signal will be significantly lowered with long off periods.
Andrew
GRedpath,
The RMS detector is the same as using “Power” Video Units and “Average” detector in our software. This should be the default setup in SEM mode.
Let me know if you have follow up questions.
Andrew
Hello GRedpath,
Unfortunately this is not possible right now. We have received this request before, and last time we investigated it, we determined it will take additional (non-trivial) development to add this. I don’t have a timeframe for when we would have this feature, but now that multiple people are asking for it, I can bump it up in priority. I appreciated you reaching out to us and also providing the standard you are testing. I will add that to our notes.
Let me know if you have follow up questions.
Andrew
lsullivan,
The FIR filter uses the standard overlap save algorithm. We do not use a library except for the FFT portion of overlap-save. Everything else is custom implemented. The maximum filter order is 1024 taps.
Regards