Carolina® AM Crystal Radio Kit
Students will construct and then evaluate separate components of a crystal radio, relating the electromagnetic structure of parts to the function of the component and then engineer the components into a complete, working crystal radio.
Using kit materials, students construct a working AM crystal radio, popular in the early days of broadcasting, to tune into local stations. They build circuit components from aluminum foil, copper wire, and cardboard tubes. Students learn how modern communication systems transmit information using electromagnetic radiation to encode a signal.
A battery-powered speaker (with internal rechargeable battery) is included to amplify the radio signal for testing and listening.
During the activity, students observe energy conversion between different forms (e.g., electrical energy to mechanical energy) and build upon their knowledge of wave properties by learning:
- How transducers convert the signal's electrical energy into a mechanical sound wave.
- The relationships between inductance, capacitance, and resonance in tuning to a radio station and building the classic LC (inductor-capacitor) tank circuit.
Designed for a class of 30 students