Arduino emits signal A (infrared) but another Arduino receives everything but A (IR-LED problem)
Sorry not enough rep to comment. Had to answer instead.

So if your schematic is correct then you just fried your LED. You need a series resistor between vcc and the LED.

If it's not accurate and you have the resistor in place, I'd check the LED anyway, it could be a dud. Apply voltage with a resistor and look at it with your cell/mobile phone digital camera, you should see it through the camera glow dimly.

If all is good then it might be the wavelength of the LED, which is 850nm. Most IR LED's I've used are 950nm, actually they all were. 

Now I don't know what the specs of your receiver are but it might be out of its sensing (is that a word?) range, also it only has a 20° viewing angle, so check the alignment of transmitter and receiver.

I'm also confused by your statement that your getting signals that don't look like IR. This makes me wonder if your sensor is hooked up properly. It could be background IR or from another source. Look around the room or test elsewhere.