Abstract: A renewable energy flashlight comprises a housing and a barrel located within the housing. A wire coil wraps around the barrel, between the barrel and the housing. A magnet oscillates within the barrel when the flashlight is shaken, generating an alternating current in the coil. Two springs at either end of the barrel cause the magnet to recoil when the magnet strikes the springs. As an alternative, rebound magnets oriented to repel the charging magnet may be installed within the barrel at either end, to cause the magnet to recoil from the ends. An electronics assembly within the housing includes a capacitor for storing charge, a rectifier connected to the capacitor, and means for conducting current flowing in the coil to the rectifier, to charge the capacitor. An LED is connected to the capacitor by means of a switch, and lights up when the switch is switched on.

Abstract: A renewable energy flashlight comprises a housing and a barrel located within the housing. The barrel has a wire coil wrapped around it, between the barrel and the housing. A magnet disposed within the barrel oscillates within the barrel when the barrel is shaken, generating an alternating current in the coil. Two springs at either end of the barrel cause the magnet to recoil when the magnet strikes the springs. An electronics assembly located within the housing includes a capacitor for storing charge, a rectifier connected to the capacitor, and means for conducting current flowing in the coil to the rectifier, to provide rectified current to the capacitor and charge the capacitor. A light emitting diode (LED) is connected to the capacitor by means of a switch, so the LED lights up when the switch is switched on.

Abstract: An electronic article surveillance system capable of reliable operation at high frequencies such as about 8 MHz, has an arrangement of transmitter and receiver antennas each lying in a flat, horizontal plane in substantial alignment with each other, with the receiver antenna positioned at the floor of a passageway at an interrogation zone and the transmitter antenna positioned overhead. Each antenna takes the form of a pair of parallel-connected, coplanar loops with the transmitter-connected loops being positioned such that electrical current flows around each loop in parallel in the same direction (a ++ configuration) and in the receiver antenna electrical current flows around each loop in parallel in mutually opposite directions (a +- configuration). The antennas are approximately of the same size and overall configuration, and they are positioned in substantial alignment so that the currents induced in the receiver antenna by the field from the transmitter antenna will effectively cancel.