I am using a 32GB micro SD card in my NanoVNA-H v3.6. I use it mainly to
save calibration (). I did not do any
formatting, just inserted a new card and started saving calibration. So far
I have saved about 7 sets and recalled them multiple times later.
After reading your post, I tried to save a screenshot. It showed as saved.
But when I tried to recall it, the recalled screen is just a grey screen
with only the saved number (8.bmp) at one corner!
Jon, VU2JO
On Thu, Mar 6, 2025 at 4:36?PM moshe.braner via groups.io <moshe.braner=
[email protected]> wrote:
I recently bought an H4 v4.3. Was looking forward to being able to save
plots from the nanoVNA to a micro SD card. But every attempt resulted in
"fail write" message. I read that it cannot handle some big fast modern
cards. Tried an 8GB card. No Go. Tried an old 1GB card, formatted
FAT32. The nanoVNA managed to save a calibration, but screenshots "fail".
Each failed screenshot save resulted (as seen from Windows) in a file
written by the chosen name - but with zero size. Tried a brand new 2GB
card, no go. Read somewhere advice to format the card using the official
SD-formatter program from the SD conglomerate. I have a very old version
of that on my Windows XP PC. Tried that. It formatted it FAT (not
FAT32). The nanoVNA accepted that and successfully wrote a BMP screenshot
file. That's been my experience. YMMV.
- Moshe N1OVN
