Image Number 2 for United States Patent #4284983.
New and unique circuitry suitable for being located in electrical appliances, and which protects such appliances from theft and unauthorized movement. More particularly, the invention discloses circuitry for providing an alarm when the appliance is both disconnected and moved. The circuitry monitors both power input and movement of the appliance, and provides a pulsating signal suitable for sounding and audible alarm until the appliance is either reconnected or the alarm interrupted by a key switch. According to one particular embodiment, a mercury interrupter is uniquely arranged to operate as both the motion sensor and the oscillator for providing pulsating power to the audible alarm.