9 ELECTRONIC DISPLAY MONITORS, LARGE SCREEN PROJECTORS CAPABLE OF PROJECTING AN ELECTRONIC SIGNAL FROM A GENERATED SOURCE AND ACCESSORIES, NAMELY, VIDEO DECODERS, SIGNAL SOURCE SWITCHERS, SCAN DOUBLERS, SCAN CONVERTERS, LENSES, MECHANICAL MOUNTING RACKS, BRACKETS THEREFOR, AND RELATED INTERFACE MODULES, NAMELY, SIGNAL INTERFACE BOARDS