Check the transmission power level. You may need to set it a notch higher.
Any other WiFi networks in the area? You may have a conflict with some. Check if you can use another channel.
Make sure that the devices and the router are set to use the same encription and protocols.
Make sure that the passwords and encryption keys are valid. If you are not sure, suppress the actual keys and generate new ones. You may need to use an USB key to transfert the encription keys: They can be quite long and use non-printable characters.
As long as you use the same router, changing the broadband modem is realy plug and play.
If you change the router, you'll need to configure it the same way as the previous one.
It's always good to have at least one device that is normaly connected by whire. If one of your computers is usualy used in a given location and is rarely if ever moved around, have that one whired.
This will give you a reliable connection and reduce the need WiFi bandwidth.
DON'T EVER suppress the beacon. Doing so will force any connected devices to broadcast it's credentials UNENCRYPTED and in PLAIN TEXT every 10 to 20 seconds. They will do that ALL the time no mather where you are. This makes it realy easy to aomeone to "impersonate" your network or pretend to be one of the allowed device to your network.
On Windows 7, DON'T use homegroup as you have an eterogenous environment, it only work if ALL devices are computers running Windows 7. It's goal seems to be to lock you into using only Windows 7.
Electro
June 2012