I am a field tech for a local cable company, i have ran into several customers that have been having issues connecting to the **** tg862g router, here is a work around that has fixed many of them.
using a computer or other device with a browser and in the web address type in the router address. for us the address is 192.168.0.1 but it varies with different cable companies. you will be asked to log in the default password is password.
once in go to your wireless settings change the channel from auto to 1, (if at the end of this process it still doesnt work try changing the 1 to a 6)
change your ssid to something simple that you can remember example: myrouter
disable the wireless encryption
disable broadcast ssid
note: disabling the encyption will leave your router wide open for any one to use, by disabling the broadcast only those who know the name of the router can connect. all other devices will have to have the ssid manually entered in order to use the wireless. this will help protect your router from unwanted connections. hope this helps :)