If you are lucky enough to have a big house, a large garden, and small children, this project just might interest you. It’s actually a telephone ringer capable of making any mains-powered device work ...

Using modulated rectangular waves of different time periods, the circuit presented here produces ringing tones similar to those produced by a telephone. The circuit requires four astable ...

We may receive a commission on purchases made from links. Cellphones are great! They have totally revolutionized the way we live, work and play. You can take a phone call atop a mountain, on the train ...