Abstract: An optical device and system and method for monitoring a fault condition in an optical device. A loop-back path couples a portion of an optical signal from a first transmission path to a second transmission path as a loop-back signal. The loop-back path includes at least one optical attenuator configured to attenuate the loop-back signal in response to at least one detected condition. The loop-back signal may be detected by line monitoring equipment, where the attenuation imparted by the attenuator is interpreted as corresponding to the detected condition.

Abstract: An optical device and system and method for monitoring a fault condition in an optical device. A loop-back path couples a portion of an optical signal from a first transmission path to a second transmission path as a loop-back signal. The loop-back path includes at least one optical attenuator configured to attenuate the loop-back signal in response to at least one detected condition. The loop-back signal may be detected by line monitoring equipment, where the attenuation imparted by the attenuator is interpreted as corresponding to the detected condition.

Abstract: An EMC sealed joint is used within electronic equipment to provide compliance with electromagnetic compatibility (EMC) standards. In one example, EMC sealed joints are used with faceplates mounted to printed wiring boards stacked side by side in an electronic equipment rack, for example, to seal the adjacent faceplates against one another and to seal the faceplates to the shelf edge portions in the rack. One type of EMC sealed joint is formed by a concave groove in a side portion of the faceplate, which receives an EMC gasket located on an adjacent faceplate. Another type of EMC sealed joint is formed by protrusions on a back surface of the front portion of the faceplate, which engage a flat surface on a shelf edge portion in the electronic equipment rack.

Abstract: A heat sink used in an electronic assembly includes mounting surfaces on a first side of a base portion and extended heat dissipating surfaces (e.g., fins) extending from a second side of the base portion. One or more electronic component boards, such as printed wiring boards (PWBs), are mounted to the mounting surfaces on the heat sink at one or more levels. Some of the mounting surfaces can be formed on mounting ridges, which define channels. Ventilation apertures located between the fins extend through the base portion such that air is drawn through the channels and up through the apertures creating a “chimney” effect. The heat sink is also grounded to at least one of the PWBS and electrically isolated from the chassis. Isolator bushings can be mounted in one or more of the fins for receiving pins extending from the chassis to insure mechanical support and isolation/dampening and to insure electrical isolation from the chassis.