Here is a collection of various alarm circuits which are very useful for engineering students and as well as in our real life also. Nowadays many engineering students are searching for various alarm ...

It beeps if the fridge door is left open for too long or hasn’t closed properly, to stop food from spoiling. There are lots of other uses as well. A refrigerator or freezer door that is left open or ...

Adding an intruder-alarm system to an existing house or apartment used to mean tedious installation of a network of fragile and often unsightly wires. The wiring problem has been neatly solved by a ...