Last year I went out with my Macbook Pro armed with iStumbler that I had downloaded after the last lecture and found a square area on "Mayflower Street" and from 4 points took readings for wifi signals and them put them onto a map using Photoshop overlapping the wifi signals where I estimated the signals to be judging by the signal strength at the 4 different points.
The wifi signals are also shown by their channel number as shown in the key on the left. And the Protected wifi signals (passwords) are shown with a tremelo line pattern across, again see key on the left of the image.
This year me and two of my newly acquired first years headed down to our spot (...not like that) by the 'dance academy' on Union Street.
Using my iPhone we looked for WiFi networks along the stretch of road out the front of the building.
This is little Jon's interpretation of the networks.
Green circles indicate a health WiFi signal strength, red, not so healthy. And the circles indicate the estimated area covered.