The simplest #radio to build #diy - a spark gap radio. #physics #science #physicsdemo #macgyver

3-Second Blueprint (English)

1. Rapidly interrupting current through a wire coil inductor induces high-voltage flyback spikes (V = -L dI/dt) that ionize a spark gap.
2. An iron-nail electromagnet pulls a flexible contact wire open whenever energized, creating a self-oscillating electromechanical buzzer.
3. Continuous high-voltage arcing across the contact gap generates damped broadband electromagnetic waves detectable by nearby radios.