Lab Day 3

Dusk-to-Dawn Light Lab

In this lab, we created a light-sensitive lighting system. A photocell was used to sense the ambient light level. A BJT was used a a switch to turn on a LED when the ambient light level becomes low.

 1. These are the calculated values of Vb for photocell resistances 5K and 20K ohms that was done during the pre-lab.

 2. This is a picture showing our circuit.

3. These are the measured values of Vb for photocell resistances of 5K and 20K ohms.The measured values are lower than the calculated values. 

4. This is a video of the operating circuit.