This circuit was designed to produce an audible alarm when the mains power is interrupted. Such an alarm is essential for anyone whose livelihood depends on keeping perishable foodstuffs in cold ...

The Internet of Things is fast approaching, and although no one can tell us what that actually is, we do know it has something to do with being able to control appliances and lights or something.

Whenever AC mains supply fails, this circuit alerts you by sounding an alarm. It also provides a backup light to help you find your way to the torch or the generator key in the dark. The circuit is ...