Signal transmitters emit acoustic and optical signals to warn, inform, or alert. Flashing lamps can be found in alarm systems in residences, jeweller shops, and office buildings. Equipped with the appropriate acoustic signal transmitters, their attracts attention to any break-in attempt. Signal towers indicate a change, such as when an error in a production chain or a new process occurs. Among the acoustic signal transmitters are sirens and horns, speakers, and microphones.