Take your exploration of transistors the next step beyond the TouchPad with this board that uses a a photo-transistor coupled with an NPN transistor to create a light activated circuit.
Nitelight is Available as a soldering kit or pre-assembled.
The NiteLight circuit further explores how to use a transistor in a logic gate to create a circuit that turns the LED on when it gets dark. This useful circuit can be embedded into any application where you need a light sensitive circuit (wearables, night lights, jack-o-lanterns...). Students can even swap out the NPN transistor with a PNP transistor (not provided) to reverse the circuit and build a circuit that turns ON when in presence of light (i.e. cabinet light or refrigerator alarm).
Each kit comes with a NiteLight PCB board, battery holder, battery, on/off switch, NPN Transistor, Phototransistor, resistor and LED.