Zetex Semiconductors have a siren driver IC Type ZSD100 available that is suitable for use in alarm systems for cars and model craft. With the addition of only a few components as shown in the diagram ...

This burglar alarm system circuit is using a infrared proximity detector that triggers an alarm when the rays falling on its sensor are interrupted. It is different from others burglar alarm systems ...

Back in eighth grade, a classmate of mine named Bruce brought in a transistor-circuit siren made by his older brother, which was installed in a transistor radio case. Immediately enchanted, I went to ...