Abstract: An end-of-branch (EOB) module system for an audio signal distribution system having a wired trunk and a plurality of wired branches extending communicatively from such trunk, the EOB module system including: a plurality of EOB modules including one EOB module electronically coupled at each distal end of each branch and trunk of the audio signal distribution system, where each EOB module of the plurality of EOB modules has a unique address together forming a plurality of unique addresses; a test system able to send a test carrier signal encoded with any one unique address of the plurality of unique addresses at a time onto the trunk; and a switch within each EOB module, responsive to its unique address to place an end-of-line (EOL) load on its respective branch or trunk, and where power for operation of each EOB module is provided by rectification of the test signal.

Abstract: An end-of-branch (EOB) module system for an audio signal distribution system having a wired trunk and a plurality of wired branches extending communicatively from such trunk, the EOB module system including: a plurality of EOB modules including one EOB module electronically coupled at each distal end of each branch and trunk of the audio signal distribution system, where each EOB module of the plurality of EOB modules has a unique address together forming a plurality of unique addresses; a test system able to send a test carrier signal encoded with any one unique address of the plurality of unique addresses at a time onto the trunk; and a switch within each EOB module, responsive to its unique address to place an end-of-line (EOL) load on its respective branch or trunk, and where power for operation of each EOB module is provided by rectification of the test signal.

Abstract: An upstanding support affixed to the floor of a plant adjacent an electric-arc furnace and having a truss member rotatably attached thereto. The truss member at its free end has a vertical support member rotatably attached thereto and upstanding therefrom. The vertical support at its upper end has affixed thereto a radius arm member. The radius arm has the same radius of curvature as the roof lining of the electric-arc furnace. A refractory spraying unit is attached to, and is movable back and forth along the length of, the radius arm. When the roof of the electric-arc furnace is swung outwardly of the furnace between heats, the truss is swung about the upstanding support to carry the vertical support and radius arm directly beneath the furnace roof. Rotation of the radius arm and movement of the spraying unit along the length of the radius arm causes the roof lining to be coated with refractory.