We decided to address the first four issues in our virtual lab. These were addressed by providing a visual environment in which the students could create a spaghetti circuit, elements whose values varied at random from the "marked value" and a breadboard in which a number of holes would automatically present bad connections. With these three elements of a real lab captured we provided power supplies to set and turn-on along with instruments to
connect in order to debug a circuit. Of course, to provide the students with actual values for their circuit we needed to perform a simulation. The simulation is accomplished by sending a file to SPICE based on the circuit element values, breadboard connections and instrument settings. The connection of the simulation to the instrument settings provides one more way in which the students experience potential real-world problems in the virtual environment.
Students normally have pre-lab assignments in which they design and analyze the circuits they will be building. Often the analysis is done using computer-based simulation
programs. Our tool - the Virtual Circuits Laboratory, (VCL)