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 ...

This is an automatic quiz buzzer system in which if more than one team presses the buzzer, the accurate delay time is taken into account and the number is displayed. Here is the simple circuit diagram ...