My Oklahome State University History: While studing Electrcal Engineering at OSU, I (Jon Miller) was asked to desigm an electronic diming system for the University Auditorium. The Silicon Contolled Rectifier (SCR), a solid state device CIRCA 1964 was incorpated in the design. Shown in the photo is the system being tested in a workspace in the power generation lab at the university. My sponsors were Dr. Bristow and Dr. Davis. The unit was installed and operational unil the University Auditorium was replaced. The system provided 30 circuits 1200 watts each. The console shown in the photo provided three banks of control. I think this was the first system soon to the the state of the art.