Features: -

• An LED to show the status of the output, this eases the installation of the optical switch.        
  
• This board can be used for an optical limit/home switch by placing the photo transmitter at the end of an axis travel.
  
• Easily reads a pulse from the spindle enabling you use it as a tachometer or to control threading.
  
• Easy connections.  Simply connect a 5v Power supply, the supplied optical switch and the output to your parallel port.

Mounting the optical switch as a timing disk/rev counter.
Mounting the optical switch as a home/limit switch.