The students constructed a simple AM radio over several weeks using components for tuning, demodulation, and amplification circuits. They tested the radio and were able to receive signals from two local radio stations. An experiment demonstrated how an AM transmission works by using a function generator to generate a signal that was modulated and picked up by a receiver, with the signals shown on an oscilloscope. AM transmission encodes an audio signal into a carrier wave by varying the amplitude of the carrier wave. The receiver then demodulates the signal to separate the audio and amplifies it to be played on a speaker.