Hello, I am new to programing and miniature computers. My idea is to have either one or two sensors places on posts across from each other. These would be about 6 feet apart. I would want them to activate a speaker when they are interrupted. I do not know if I am in the right place or not, but I would be very grateful if I had some guidance. I do not know which components or computer would work best for this. I also don't know how to program it, maybe there is a tutorial similar to this idea I can follow? I have a small sketch attached. Thank You.