I have just bought a R Pi 3B+, on which I am running the latest NOOBS.

I bought it to run some specific software, which I have now managed to
get set up and working on a 32Gb card. The only other suitably large
card I have is a 16Gb, onto which I would like to write a backup copy.

I have tried to use Win32DiskImager, but that complains that is cannot
copy from the 32 to 16Gb.

I also have an old usb mobile dongle, which has a built in SD Card
slot. That just seems to want to install its mobile software - without
access to the 16Gb card.

What to try next please?

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