The board is from an old coffee machine.
The optical sensor is used to detect the presence of a linear ram.
I am just trying to understand the circuit, and figure out what that 3 pin black component is.
Can anyone give me some clues please.
I don't have access to the machine at the minute, but I do know tha pin 1 is 12V with respect to pin 3.
Here is the circuit diagram as I see it, and a photo of the actual board, with a couple of scribbles showing the optical sensor orientaion.
Is there a way to determine what diodes they are?
I get the 680 ohm resistor for the LED and the decoupling capacitor, but that's all.