I got my first Nano VNA yesterday, a friend who used to live 10 miles away, now lives 1000 miles away bought it for me along with jumpers and adapters. Today I set up "presets" for 80, 40, 20, and 2 meters.
I researched a bit and found out it could be a small SD card, all I had was some 64-gig and one 16-gig card, well the 64 failed but I did manage to format the 16 to fat32 and that just got finished can see this device is going to be very handy, and a bit of a challenge, but that is OK. I have always believed that learning is a lifelong experience, and if you stop learning you stop living.
As I try to learn more about this thing, I am sure I will be visiting this page frequently.