On/Off vs 101 Circuits

Light every circuit, one carefully planned tap at a time. Tap a tile to flip it and its neighboring lights. The rules take seconds to learn, but finding the perfect solution requires logic, planning, and pattern recognition. Play 150 handcrafted puzzles, solve a fresh daily challenge, earn three-star solutions, and use optional hints whenever you need a nudge. There are no timers, no accounts, and no pressure just satisfying logic puzzles you can play anywhere.

earn electronics by building circuits and seeing how they work. In 101 Circuits, connect components, inspect signals on the oscilloscope, and adjust your wiring to match a target waveform. Begin with batteries, resistors, and simple connections, then explore filters, transistors, amplifiers, logic circuits, and oscillators. See how a capacitor smooths a signal, how a transistor switches current, and how connected components shape a waveform. Each exercise has a clear goal: produce the required output signals. Different circuit designs can satisfy the same requirements, giving you room to experiment and understand the result. The built-in Learn library explains component symbols, circuit behavior, and connections through diagrams, formulas, and practical examples. Circuit guides help you understand the principles behind each exercise. Use Sandbox to create and save your own circuits. Change resistance, capacitance, supply voltages, and signal settings, then inspect their effects. Add LEDs, explore different connections, and put what you have learned into practice. Zoom into waveforms, inspect voltage and current, and use Undo and Redo to revise your circuit. Saved progress lets you return to your work and continue at your own pace.