I have a Pi 4 on my boat in France. It sends back monitoring information like battery voltages while I'm not on the boat.
Currently it connects via a TP-Link MR200 4G router which has a free.fr SIM in it. This has worked OK for many years but I think the damp must have finally got to it because last time I was on the boat (in March) it was very flakey, I had to keep restarting the router or even power cycling it.
I'm going out to the boat again in a few days time and I'm looking for a quick and easy (and cheap) way to restore the connection while I test to find out whether it's the SIM is faulty or the MR200 router.
So can anyone recommend a 4G dongle that is known to work well in a Pi
4? Then I can put the free.fr SIM in that to see if the SIM is OK (and there's a Free shop nearby if I need to replace it). If the SIM is OK then I'll know the problem is with the MR200 router and I can replace that.