A Quarter Acceptor that rejects penny's, nickles and dimes. If the coin inserted is smaller than a quarter it will fall into the coin return. A larger coin will not fit. If a Quarter is inserted it will slide down a shoot and block the IR light from hitting the IR detector causing a pulse to be sent to the microprocessor. Connect an IR LED and detector to send a pulse to your favorite microprocessor such as an Arduino or Raspberry Pi.
I will also be designing a coin box and vending device for this soon.
Example Video:
https://youtu.be/7oyIWBql5Mk