Gui for Monitering Signal Strenght

[Circlenaut]

I've just finished setting up a Mint 9 x64 desktop for my parents. They connect to the Internet via a WISP (In Rio de Janeiro, horrible customer service put decent connection). I'm worried that if they need to change providers they'll also need to reposition the antenna. I used airodump-ng's deciBel output to find the sweet spot, but that's way beyond their ability. Is there another gui program that gives an output in decebels (the percentage bar is not very useful)?