You have the router at defaults, broadcast a simple SSID and use WPA?
I've been helping my dad's workplace to set up a wireless network and I've come across a problem. We recently installed a 15 dbi antenna to a linksys wrt54gs to boost the signal to the surrounding buildings but the connection keeps disappearing. The connections close to the antenna never lose connection but connections further out will drop it and lose it anywhere from a minute to several hours. However, regardless of proximity of the computers all of them experience speed fluctuation anywhere from 36mbps to 2mbps. We've had this problem with two different network providers, I've changed the wifi channels, changed the encryption and the router's firmware is completely up to date. Can anyone tell me what might be going on? Is the router dying, not getting enough power to the antenna, what? Thanks.