Range on my Macbook is poor

Hi, I bought my Macbook in 2006 (the 1.83ghz version with OSX Tiger), and have had no problems until a few months ago - when using airport, my wireless range has suddenly become very limited. I know it is not a problem with the router, as other computers work fine with it, and I have tried my Macbook on many other routers and still get the same problem. I have all the latest software updates installed, have reset safari etc numerous times, completely formatted the computer, upgraded the RAM, checked the connections to the Airport card (for fraying etc) and tried changing settings/channels etc on my router - all of which failed. I've even taken it to a mac ''genius'', who couldn't seem to understand that when the router was nearby (as in the shop) the connection is fine.

Does anyone have any suggestions? All I can think of doing is replacing the Airport card, has this worked for anyone? Thanks

It could be the airport card is beginning to fail but it could also be the antenna within your MacBook. Sometimes swapping out the display on a MacBook or MacBook Pro will dislodge the antenna from its original position and cause weak or limited range reception.

If you haven't ever opened up your MacBook or had it worked on, then an antenna problem is unlikely. It's probably the airport card. Here's a link to the ifixit web site where they sell replacement airport cards for your machine and also have instructions on how to replace it yourself. Link

Regards.