AirPort Extreme first generation drops connection

The airport extreme at my brothers house is dropping Wi-Fi every 30 minutes. This is a first generation Apple extreme setup in 2007. The light stays green but the Internet is gone. That is, the Wi-Fi from the Apple extreme is gone. I unplug the electricity plug from the back of the extreme, wait a few seconds, plug it back in to the plug on the extreme and it works for another 30 minutes.

What is going on? This is not a Comcast problem it seems.

Regards,

Steve