JCM Part No . 960 - 000076R _ Rev . 1 © 2007, JCM - American Corporation B - 2 Appendix B World Bill Acceptor (WBA® - 1x/2x - SS & SS2) P P 14 Photo - coupler isolation – an LED and photo sensor combination utilized to isolate electrical                                                    signals . 15 Pictographs – small internationally recognized safety and attention symbols placed to the                                 left of Notes, Cautions and Warnings throughout the manual . 16 Pusher Mechanism – a device used to stack received bills into the Cash Box . R 17 RS - 232C Communication – a common serial data communication standard protocol . S 18 Sensor – a photo sensitive device and LED combination designed to detect timing and                       movement events . 19 Solenoid – an electro - magnetically retracting piston that mechanically moves a lever arm or                          other actuator within the UBA T 20 Timing Belts – rubber belts used to transport notes (bills) inside the Validator . W 21 WBA – acronym for World Bill Acceptor .