Dragon Tamer
Member
The transmitter and receiver don't need to be any kind of a coded signal, you can just have an IR LED and an IR NPN photo-transistor. Just connect them to your voltage supply and have the current flowing into them limited appropriately. If you're having problems with your photo-transistors picking up a lot of stray IR from sunlight and what not, color your receiver red, and put it into a tube (a paper one is good enough, as long as it's black inside) and make the tube about 1" long.