[GraemeJ]

A SIM card is not required to set up a WLAN hotspot. It's only required to access the internet.

I learn something new every day.  The only times I have ever used a hotspot is via my phone, in order to get TV when the internet goes down (not totally uncommon where I live).  Obviously, that does require internet access and I made the (unwarranted) assumption that a SIM was a necessary part of the mix.

Just out of curiosity and using a very old Android tablet (running 4.4) I found I could set up a hotspot.  Now I need to discover whether I actually need it  .