My house has a few antennas on its roof. We act as a repeater station for some other customers running 802.11b in the valley below the house. I get my internet via another repeater tower a few miles away.

Our ISP reported some intermittent interference that he had trouble tracing. At first he thought it was our 2ghz cordless phone, but we couldn't reproduce the interference problem each time we turned on the phone.

I arrived one day to find larger antennas on the poles on our roof, and I haven't heard him complain about interference since.

He has a lot of experience with this. Are there any specific questions you'd like me to forward to him?