How do I turn off Wi-Fi on my Apple Airport Time Capsule or Airport Extreme?

In AirPort Utility, you can disable a base station offering Wi-Fi service.

1. Launch Applications > Utilities > AirPort Utility.
2. Select your base station and click the Edit button.
3. Enter the base station’s administrative password, if prompted.
4. Click the Wireless tab.
5. From the Network Mode pop-up menu, select Off.

Click Update, and the base station will restart and load the new settings.