Hey experts! I've designed an infrared detection circuit to drive a motor, but I need the circuit and my math checked. I tried 5Spice, but I can't get my head around it. Circuit image attached. Do you know about how far I would be able to detect someone crossing in front of the light? I need 10-20 feet. Even farther would be great! Edit: I should also mention that the TIP41C transistors are the correct components, but I am only using what Eagle had in its library for the other components, so they are not necessarily to spec.