I have NEVER had a problem with Nano VNA SAVER on my Win10 desktop or laptop.
It connects to a COM port.
It allows me to choose a CAL file which I made earlier (one CAL file for each ham band).
I pick the sweep range.
I usually pick reasonable frequency intervals (mostly one band at a time).
And it takes maybe 10 seconds at most to sweep any ham band.
I often look at 6 graphs at once:
relection coefficient, return loss, SWR, impedance, phase, and Smith Chart
Sometimes for checking filters, I will sweep 1 MHz to 30 MHz, or 130 MHz to 150 MHz.
I¡¯ve never had any problems of any sort!
de barry k3eui
Philadelphia area
Barry K3EUI