We don't do very many 'techtip' type of posts here, but we thought this might help some of you if you have been getting wi-fi issues with the iPad, plus it is weird!
If you are having problems connecting to your wi-fi network, take a moment and check your brightness level. Is it all the way to the left? This might be your problem.
Apparently, a number of people have been having issues when the screen is dimmed, especially if you are trying to use the iPad in a darkened room without waking/disturbing your partner, as did Scott from the PadCast show, which is a great podcast all about the iPad, and also where this tip comes from (Episode 12 at 48:21).
Scott recalls that his old Newton MessagePad 2000 would make an audible hum when used with a dimmed screen, and it seems that a similar thing might be happening with the iPad when the screen is dimmed. It is this electrical hum that is creating interference and preventing a good wi-fi connection.
It sounds a bit strange, but Scott says in the podcast that he and others have seen an immediate improvement in signal strength on the iPad as soon as they turned the brightness back up.
Apple have even cited this as one of the reasons that you may experience wi-fi issues in their support article, so it is official.
We hope this helps someone (plus it gave us a chance to include a picture of the classic Newton and plug a good iPad podcast). However, we cannot be held responsible for the consequences of flood-lighting your darkened bedroom while your other-half is trying to sleep, you're on your own with that one!