Abstract: A circuit and a method for controlling the dimming of incandescent lights using a pair of antiparallel connected SCRs which are fired at the same frequency as the frequency of the AC line power to achieve phase control of the power supplied to the light. Only one SCR of the pair is utilized in the 0% to 50% brightness range while both SCRs are utilized in the 51% to 100% brightness range.

Abstract: A dimmer module including a dimmer circuit for use in controlling lighting used in theatrical and architectural operations. The module features a low cost, compact, thermally efficient design incorporating circuit breakers, a power device including solid state switches, and toroidal chokes, all components being interconnected using with prefabricated tooled interconnections eliminating conventional wiring in a housing adapted to make all external connections on a plug in basis. The housing structure incorporates a built-in handle and a plurality of parallel air flow paths to maximize cooling efficiency.

Abstract: A self-contained portable unit for use with theater and television dimming systems and, in particular, with one control console of a microprocessor-based lighting control system having a data display device such as a CRT. The unit includes a digitizer tablet, a stylus and an overlay to be placed on the tablet. The keyboard of the console is reproduced in the overlay in the form of keys replicating indicia printed or silk-screened on the overlay. An area is also provided on the overlay for placement of the designer's lighting pattern layout. Lighting pattern information and lighting levels are entered into the system by the unit by touching the stylus to specific points in the layout and to specific key indicia selected by the user. Initially, each symbol on the lighting pattern layout is defined by using the unit or the console to enter the channel, the light level in each channel, cueing instructions, or other information which the symbol represents into the system.