This musical light alarm circuit is very simple, uses only 7 components, a LDR and a 3.6 V battery or 3 x 1.2 volts rechargeable batteries. The well-known UM66 is used as the sound generator and will ...

Two lamps connected in series with an open switch and a cell The circuit diagram shows a circuit with two lamps connected in series. If one lamp breaks, the other lamp will not light. The current is ...