How did Tektronix find out about the problem?
Tektronix discovered the potential hazard after a customer instrument with a damaged power supply circuit was received for repair. In that particular case, the user had caused the defect by inserting a longer than specified screw or other thin metal object into the grounding post. Following a diligent analysis by Tektronix safety engineers, it was determined that this form of improper usage could have exposed the user to line-level voltage if the instrument had not been properly grounded.
