Can I change baud rate?

[daehwa]

Hi,

I am using nanoVNA V2. When I see the built-in display of the VNA, it seems to sweep all frequencies pretty quickly (though I don't know how many data points it sweeps but the graphs look reasonable).

But when I try to get only 101 data points using serial port, it takes 1.1 sec per sweep. I think the bottleneck comes from serial communication. The VNA firmware is currently flushed at "baudrate=9600" (originally).

Is it possible to change the baud rate using code in this repository and is there anyone who successfully flush its baud rate?

I hope to see your advice!

Thanks.

[nanovna]

This is correct, the sweep rate of the old hardware version is 100 point/s so it will take 1 second for a full sweep. There are newer hardware versions with faster sweep: https://nanorfe.com/nanovna-v2.html

[daehwa]

Thank you so much for the quick response! Now I understand the bottleneck comes from the frequency sweep.

I have one more question. I want to know whether current protocol can sweep a few specific frequencies.

Specifically, if I need data from a few frequencies (for the purpose of compensating speed), and if the frequencies are not in an even step (e.g., four frequencies 0.7, 1.16, 2.0, 2.95GHz), is it possible to get return loss value of those frequencies? When I look into the code, the protocol seems to sweep in a specific range with a specific step (in the _updateSweep method). But aforementioned four frequencies are not in an even step, so I should sweep the redundant range as well. If I try to repeatedly change the sweep range (i.e. use set_frequencies andset_sweep methods every loop), then I lose the speed.

Thank you for the helps!