WiFi Connection failures with Pi 3 and Pi Zero #47682
I've been working through an obscure issue with my WiFi connections.
Suddenly, for no obvious reason, The Pi Zero and Pi 3B that I use with my scope stopped connecting to my home WiFi network.
It was strange, they could both see and connect to other networks, just not my home WiFi. I could sometimes force it by using raspi-config but it wouldn't stay connected through a reboot.
Finally found something, a mention that WiFi channels 12 and 13 were not enabled in the Pi Zero and Pi 3. Apparently they are only available in some regions, setting the country code in raspi-config is supposed to resolve this but doesn't seem to, at least not permamently.
My WiFi was on channel 13 and when I set this to a lower channel the Pis started working again.
It appears that what needs to be done is edit the /etc/default/crda file:
'sudo nano /etc/default/crda'
change the REGDOMAIN= line by adding your country code - in my case GB
Save and reboot.
Useful commands are:
'iwlist wlan0 channels' gives a list of channels, before I had 1 to 11, and after 1 to 13.
'iw reg get' returns the country code
'sud0 iw reg set AA' will set the code but not permamently.
There's quite a lot on this available, but you seems to need to know that the channel number is involved to find it.