K1003 Joule of the Night – Darkness-Activated LED Circuit Kit Introduce your students to energy-efficient circuitry with the K1003 Joule of the Night kit. Based on a “joule thief” design, this project can power up to 12 LEDs in parallel using just a single 1.5V AA battery. A built-in Light Dependent Resistor (LDR) and transistor function as a darkness sensor, automatically switching the LEDs on when the lights go out. Essentially, it’s a battery-saving, light-activated LED driverIdeal for STEM learning, the kit demonstrates core principles of electronics, energy conversion, and sensor-based automation. Students can explore practical applications such as night lights, backlights, or even a visual hour indicator for clocks. The terminal block mounts for the LDR and LEDs offer flexibility, allowing easy repositioning of components anywhere on a model or enclosure.Perfect for classroom demonstrations or hands-on learning projects.Shows energy conservation and transfer (magnetic → electrical).Demonstrates switching circuits and how transistors work.Makes a practical link to sustainable design: using nearly-flat batteries instead of throwing them away.Encourages experimentation — students can change the LED, add different inductors, or try different zener values to see how output changes. SKU: K1003 Category: Kits
