Infrared system Basic version
The SF4/5 Infrared System is the base version of the detection of the rotating ball. This Infrared System is most used and the least expensive version. A constant infrared beam is present between the diode and the photocell which is interrupted when the ball passes. Each full rotation of the ball causes two interruptions which are converted into two electrical pulses.
More information about the Infrared System can be found in the SF4/5 Infrared 360º click system.