The circuit provides a simple illustration of a door phone intercom system having a two-way communication using the features of LM386 amplifier. Intercom – short for intercommunication, is an ...

When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Since the introduction of the first analog intercom systems 40 years ago, it would be easy to ...

Forbes contributors publish independent expert analyses and insights. I am an investigative attorney and physical security specialist. Many buildings, including apartment and condo complexes, are ...

Ever since vehicles were first invented around 3500 BC by the Babylonians, the problem of vehicle theft has been a constant reminder of the vicissitudes of ownership and property protection. Since the ...