Here is an ultra simple automatic light switch circuit for bedrooms. After construction, connect the input terminals of this circuit in parallel to the internal buzzer terminals of a Quartz-Alarm ...

Discover how to build a simple wireless power transfer system at home using readily available components like enameled copper wire, an LED, a 2N2222A transistor, and a 9V battery. This step-by-step ...

General purpose hobby circuit of a simple light fence security beeper is presented here. This circuit can be used as a door alarm, gate alarm, pathway alarm, etc. Any 12 Volt dc power supply can power ...