The ones i got are matched (according to rapid). They are most likely a "junk pair" though.

When i was testing the room was fairly dark. The LED did light up when i shon a lamp into the PT but without a bright light it stayed off until i shon the emitter into it.

Rapid dont sell the ones you mentioned but they do have some that say "Demodulated output signal can directly be decoded by a microprocessor". Is there such thing as an emitter that modulates itself or will i need to find another IO pin for that.

This is my first time dealing with IR and it seems i dont know much about it. When i was at school a teacher said i could use it in the same way as an LED and an LDR. Nobody said anything about modulating it.

Lets just make sure i understand how this works. The emitter is modulated at a set frequency. For a 3 pin PT that has a demodulated output does that mean that even though the beam is modulated i will see a steady output?

Would this emitter be suitable with this PT (55-0902)? The emitter looks relatively powerfull and the PT has a demodulated output, IR filter, "High immunity against ambient light" and is highly sensitive etc.

Both sides will be set about 7cm into holes which should stop any external light getting into the sensor. They will be just over a meter apart but i want this to work over 2M to make sure its reliable.