skasdorf 2021/07/01 15:47

Hello,
Hopefully I'm posting in the correct place.  I'm attempting to use the python firmware to control the nanoVNA-V2 from a raspberry pi.  However, I'm running into issues when using the data command.  Here is the basic excerpt from the code that I am running:

>
> start = 1e9
> stop = 2.5e9
> steps = 101
> OutputFileName = "S11.s1p"
> def main():
> nv = NanoVNAV2(steps)
> nv.set_sweep(start,stop,steps)
> nv.fetch_frequencies()
>
> s11 = nv.data(0)
>

However, a large portion of the time s11 is a half filled array and the remaining entries are zero.  If I call nv.data(0) a second time, this problem seems to happen less often.
An additional problem that I am having is external calibration.  Basically, I measure the SOL standards using the same method as above and save those s1p files using them for calibration.  However, when I calibrate, I don't get the same S11 for the DUT as the QT-GUI software does.  Frequency range and number of steps are set the same in both.  Does anyone have any ideas?