Turning Off Wi-Fi for Personal ComputersMost computers and wireless If your router does not support a built-in feature to turn off Wi-Fi, you have only a few options as explained below.
Removing Wi-Fi Adapters and AntennasIf your computer's Wi-Fi adapter is connected by cable or inserted into a card slot, you can detach (remove) it to guarantee the Wi-Fi radios are disabled. Follow the recommended procedures for your operating system when removing network adapters, as improper removal can cause you to lose data
Some wireless routers feature external, detachable antennas. Removing these will affect the ability of the router to use Wi-Fi but will not turn off Wi-Fi.