Abstract: An electronic key and lock system. The key unit is plugged in the unit and electrically interconnected therewith only through the leads. Each unit is fitted with a contact strip matrix provided with slots which allow access to the points of intersection of the contact strips from the external face of the unit, the user being provided with conductor pins that can be inserted in the slots so as to set up different combinations. Each unit contains electronic circuits designed to generate (in the case of both the key and the lock) and to detect (in the case of the lock only) a signal in which at least one parameter varies as a function of the established combination, the lock incorporating an electrical power supply for the electronic circuits of both units.

Abstract: An alarm system for automobiles, which is actuated when an unauthorized person tampers with the automobile. An inductive coupling is made with the automobile electrical system so that a variation in current flow in the system activates the alarm. An actuating switch of the reed type is made operative by the driver utilizing a magnet. A deenergizing switch, of the reed type, located remotely from the actuating switch is used to make the system inactive at the driver's option. An auxiliary reed type switch is located adjacent the deenergizing switch and activates the alarm if an unauthorized person attempts to use the deenergizing switch.