1. Make sure you have set the correct country code using raspi configuration.
sudo raspi-config
[[File:Raspi-config-wifi-1.png]]
[[File:Raspi-config-wifi-3.png]]
[[File:Raspi-config-wifi-3.png]]
2. Use the 'iwlist channel' command to view the currently allowed frequency bands to be connected. These values are different for different countries.