Blinking an LED with three resistors and a capacitor. Ok, ok… one of the resistors is a light-dependent resistor, but still. In reality, this is a classic relaxation oscillator. The capacitor ...

It is focusing the beam on a light dependent resistor to the right which looks almost like a red LED due to the intensity of the light. The simplicity of this circuit is fascinating. On the ...

A push-to-break switch is used to activate a fridge light - when the door is closed the switch contact is open, breaking the current flow. When the fridge door is opened the switch contact is ...