Jim Lux 2021/09/23 09:27
On 9/23/21 8:30 AM, ward harriman wrote:
> I don’t know how to do it with nanoVNA saver but you can probably do
> it with SimSmith. It would require writing a modernly complicated
> script. If you’re interested, drop me a note directly.
>
> ward dot harriman at gmail dot com
>
> ward
>
You can also use the nanovna.py command line utility (which provides a
wrapper around the console commands). The challenge is that you won't
be able to get a long series of samples at a regular rate, unless the
rate is on the order of 100s of milliseconds/sample. The firmware
isn't really set up for the equivalent of a spectrum analyzer "zero
span" function.
What you might be able to do is set the number of frequency points to a
small number (I can't remember if it's hard coded to 101), then
repeatedly do sweeps.
You might also be able to use one of the diagnostic functions to read
the nanovna from the console, but then, your timing is going to be
limited by the program that sends the serial commands. The nanovna is
probably pretty consistent in latency between when command arrives and
when data comes back. I would think, off hand, that getting samples
every second is certainly doable.
What is probably not doable is getting, say, 100 Hz measurements (if you
were going to do something like measuring heartbeats or microdoppler
effects)
The *hardware* in the nanovna can certainly do this, but to get what
you're looking for might require rolling your own firmware (or
convincing someone else to do it). Fundamentally, the nanovna samples
at a 1kHz rate (it acquires 1 millisecond of samples, then processes
them), so getting a ~1kHz data stream out is conceivable. Getting a 100
Hz data stream is definitely doable - allowing for time to grab the
samples, process them, then format for sending them out the virtual
serial port.
>
>> On Sep 23, 2021, at 6:30 AM, mrest@umd.edu <mailto:mrest@umd.edu> wrote:
>>
>> Hello,
>>
>> I am using NanoVNA Saver to record some experimental sensors and am
>> in hoping to get some longer time domain data ideally at a single
>> frequency. I have been using NanoVNA Saver to sweep at a very narrow
>> 1 MHz band but am limited to the 101 points per sweep which makes
>> looking at sensor response to lower (physical) stimuli frequencies
>> very difficult. Is there a way to record the continuous sweep over a
>> set sampling time?
>
>