The document outlines a lab exercise for building a dusk-to-dawn light circuit using a photocell and a bipolar junction transistor (BJT) to control an LED's operation based on ambient light levels. It includes detailed instructions for measuring voltages, performing calculations, and demonstrating the circuit's functionality to a teaching assistant. Additionally, it covers the principles of dependent sources in the context of MOSFETs, discussing their operational characteristics and providing procedures for conducting an experiment with voltage-controlled current sources.