Reboot your computer and do not connect your adapter to it yet.

Once logged in, monitor the kernel messages using the tail command:

Insert the adapter, and you should see something that resembles the following screenshot. This shows the default regulatory settings applied to your card:

Let's assume that you are based in the US. To change your regulatory domain to the US, we issue the command iw reg set US in a new terminal:

If the command is successful, we get an output such as the one in the following screenshot in the terminal where we monitoring /var/log/messages:

Now try changing the card to channel 11; it will work. But, when you try changing it to channel 12, you get an error. This is because channel 12, cannot be used in the US.

The same applies for power levels. The US only allows a maximum of 27 dBm (500 milliwatts); thus even though my adapter has an advertised power of 1 Watt (30 dBm), we cannot set...