Abstract: An apparatus for determining when a door connected to a wall has opened. The apparatus includes a mechanism for transmitting an optical signal from a first point to a second point. The apparatus includes a mechanism for interrupting the signal from reaching the second point from the first point when the door is open. The interrupting mechanism contacting the transmitting means. A method for determining when a door has opened. An apparatus for interrupting an optical signal transmitted from a first point to a second point through a first fiber and at least a second fiber when a door is opened.

Abstract: An apparatus for determining when a door connected to a wall has opened. The apparatus includes a mechanism for transmitting an optical signal from a first point to a second point. The apparatus includes a mechanism for interrupting the signal from reaching the second point from the first point when the door is open. The interrupting mechanism contacting the transmitting means. A method for determining when a door has opened. An apparatus for interrupting an optical signal transmitted from a first point to a second point through a first fiber and at least a second fiber when a door is opened.

Abstract: Any attempt to remove the first element or the second element from the protected item will cause the ends of the sensor cable second element to pull out of the channels of the third element, or if the sensor cable is cut, a general failure to communicate signals between the various sensor cables will occur and this failure to communicate can be sensed by an alarm system thus causing an alarm condition.

Abstract: An apparatus for linking a cable to an object comprising a first element having a first channel passing therethrough which receives a connector that fixedly links the first element to the object. The first element also has a second channel passing therethrough which intersects the first channel and through which the cable extends. In addition, the apparatus is comprised of a blocker disposed in the first channel for preventing the connector from being removed. In a preferred embodiment, the apparatus includes a second element having a chamber, and a third channel passing therethrough and intersecting the chamber such that the chamber can receive the first element, and the second channel and third channel align so the cable can extend through the first element and the second element by way of the second channel and third channel.

Abstract: A security system for monitoring comprising an optical source for producing optical signals. The security system is also comprised of a detector in optical communication with the optical source which receives the optical signals produced by the optical source. The security system additionally is comprised of an electrical circuit in communication with the optical source and the detector, which is either in a first state or a second state. The circuit controls the optical source and determines whether the optical signal received by the detector is such that the circuit is in the first state or the second state. The circuit also indicates when the optical signal received by the detector is such that a transition from the first state to the second state is imminent to occur. The presence of this imminent transition is otherwise called the pre-alarm condition.

Abstract: An apparatus for linking a cable to an object comprising a first element having a first channel passing therethrough which receives a connector that fixedly links the first element to the object. The first element also has a second channel passing therethrough which intersects the first channel and through which the cable extends. In addition, the apparatus is comprised of a blocker disposed in the first channel for preventing the connector from being removed. In a preferred embodiment, the apparatus includes a second element having a chamber, and a third channel passing therethrough and intersecting the chamber such that the chamber can receive the first element, and the second channel and third channel align so the cable can extend through the first element and the second element by way of the second channel and third channel.

Abstract: A lock for preventing the removal of an object having a first portion with a smaller cross-sectional area than the cross-sectional area of a second portion or the cross-sectional area of a third portion between which the first portion is disposed comprised of a housing having an opening and a removable member. The removable member is disposed in the opening such that when the member is removed at least the second portion or the third portion of the object can fit through the opening in the housing, but when the member is disposed in the opening, only the first portion of the object can fit therethrough. The lock is also comprised of a cable which extends through the housing. The lock can additionally include a device for determining when the cable no longer extends through the housing. The determining device is in communication with the cable.