21 RADIO AND TELEVISION ANTENNAS AND RELATED SYSTEM COMPONENTS AND ACCESSORIES-NAMELY, AMPLIFIERS, ATTENUATION PADS, COUPLERS, CABLE CONNECTORS, CHANNEL TRAPS, LINE SPLITTERS, LINE TAP-OFFS, MATCHING TRANSFORMERS, OUTLETS, PLUGS, PRE-AMPLIFIERS, RECEPTACLES, SOCKETS, AND WALL PLATE COVERS