Nicolas putting together a trial of the circuit.
Used AA Batteries to power LED + transistor. Needed a multimeter to test voltage output by the diode amplified by the transistor.
We were aiming to get a big jump in the number on the multimeter when we cut the beam between the LED and the Diode. At first when we cut the light between the LED and the diode there was only a small difference, so Nicolas added in a transistor to amplify and the difference between that and when the beam was broken was much greater.