[pip08456]

Originally Posted by foddy

Don't forget that interference may not be Wifi related - some cordless phones, bluetooth, wireless video senders, etc. all use the same frequencies.

It is possible to get little USB devices (spectrum analysers) to check for interference, but it may just be easier to try different channels. Don't forget that the channels overlap.

Is it worth £80-£100 though?

Also, it may not be interference. In the past I've had problems on a laptop where disabling the "allow this device to be put to sleep when not in use" (or whatever it's called) checkbox has cured a similar problem.

If you need a stand-alone wifi access point, I can't recommend the Apple airport extreme enough, although it is a little on the expensive side.