I have used inSSIDer to select the best channel for my home, have unplugged every electrical item that may be causing a problem and I don't get any improvement on my wireless speed.
All inSSIDer sees is routers.
A lot of the times the routers are all using a channel, usually higher such as channel 11.
Often lower channels are jam packed with cordless doorbells, baby monitors, wireless home alarm systems, some (not most) cordless phones, microwave ovens, wireless TV transmitters, bluetooth keyboards, bluetooth mouses etc etc.
Sometimes the busiest channel on inSSIDer can be the best channel to use. Routers on the same channel doesn't cause to much of an issue, they can co-exist quite well. As wireless doorbells etc are not as regulated / digital, being on a channel these use can cause so many more issues (and the worst part, you have no idea they're there).
Commonly these devices use channels 1 - 6, but a lot of devices are using the higher channels too.
Also it's important to note channel overlap. So really only channels 1 6 and 11 are free. If somebody goes on channel 4 it messes up the whole spectrum.
Most devices default to channel 1 6 or 11. A device on channel 6 will overlap from channel 4 to channel 8. So if you see a device on channel 6 and choose channel 5 or channel 4, you're still getting interference from the device on 6. If you choose channel 2 or 3 you'll be interfering with a device on channel 1.
See here for the overlapping on channels
http://en.wikipedia.org/wiki/File:2.4_GHz_Wi-Fi_chan...
Edited by ukhardy07 (Tue 30-Jul-13 14:41:26)