(unrelated to librem mini)
I removed the antenna wires from the wifi module inside my mini pc (acemagician) in order to airgap it (no internet or network access) Somehow I was able to connect to my router via 5G. How was this possible? The module is fused onto the keyboard. Isn’t it enough to remove the antenna wires? Is there another part that allows the mini PC to connect to the router? Maybe the antenna is embedded inside the motherboard?
side question: Does the Librem mini have this issue? I am considering a Librem mini but I want to airgap it. I want it to be completely unable to connect to internet.
You may have to remove the card entirely. I have a WiFi card in my desktop with an external antenna. If I remove the antenna, I can still connect to WiFi with it, although I have to be very close to the modem. So I don’t think you removed the antenna per se, but rather its “extension.”
In my opinion, if you want to airgap something then don’t even put a WiFi module in it. As it happens, the WiFi module in the Librem Mini is optional so save a few dollars and order it without the WiFi module.
If you ever really have to make the network available to something that is airgapped then
a) you are probably better off using ethernet rather than WiFi, and
b) if you insist on WiFi then you can use a suitable USB WiFi dongle.