50 pairs 5mm 940nm Infrared Diode LED Emission and IR Receiver

Using these as sensors with my model railroad to determine when a train is passing a specific point. These are used to trigger electronic circuits to control actions like crossing signals and gates. The transmitter (clear) and receiver (black) work best when placed on opposite sides of the track. They can also be placed under the tracks pointing up, and angled slightly toward each other. When the train breaks the beam, the circuit turns on a small small relay that controls the signals. Can also be used to control lights on a control panel to indicate when hidden tracks are occupied. Only complaint - on the photo sensor (black) it wasn’t clear which side is cathode / anode. After experimentation, it appears to be the opposite of standard protocol for LEDs. In other words, long leg is connectedto minus; short leg to +

These worked perfect for what I wanted. Less than 5 stars because the data said I could expect 18 to 20 meters range, which is extremely optimistic. I would say 18 to 20 cm is more like it. Hint: plan to put the spec'ed 100 ma thru the transmitter to get any kind of range. Also, the receiver may have a 45 degree FOV, but the transmitter needs to be pointed nearly directly at it. And to correct an answer to a question, the receiver is a photo diode, and the longer lead is the anode on both - but the receiver needs to be reverse biased. I used 41 ohms between the LED and 5V, and 620 ohms on the receiver.

This product work as I wished to control a linear actuator. The one trick was that the I.R. receiver's (the black component) anode is the short lead. This is the opposite from the normal configuration of a diode. The reason is that the receiver is not a diode, but a transistor.

That seem ok don’t know why I ordered them they didn’t work at 3 volts

Misleading product description. It states 2.7~5.5V but that is only for the receiver. The emitters are only 1.2-1.5V, so be careful. Be sure to read the entire description and not only the little tagline under the title!

It comes as pair and low cost looking for small version of the revive led ?

No worky, at all. Maybe I'm doing something wrong, but dammit...It's just two leads.

Works exactly as they are supposed to

Came quickly and works well.

There are errors in comments made by some customers. First, the IR receiver is not wired backward. To have a photo-diode act as a receiver it must be reversed biased. Hence why some people have commented it is wired backward, not so. Second, the receiver is not a photo-transistor, it is a photo-diode, as advertised. A transistor has three pins! Concerning the distance range between emitter and receptor, a quick test gives me ~12cm. The 45 deg. angle of reception is ~ correct. In short you get a combo of emitters and receivers for basic use at a descent price.

The emitters have a Vf of around 1.2V (was able to pass 10mA at that easily). 20-30mA at around 1.3V to 1.4V.The receiver is a photo diode. When it detects IR it will conduct from the short leg (positive) to the longer leg (negative). With 30mA in the emitter I found a Vf of the receiver of about 260mV.My "longruner TC1" parts tester didn't know what to make of the receiver (even with a constant DC light source) but a basic digital multimeter showed the directionality and Vf of the receiver.

The package isn't marked. But the clear units are IR emitters, and the black are receivers.When used as the high leg of a voltage divider, with a 10KΩ resistor to ground, a receiver passes just about full voltage from an IR LED and about 15% with a bog standard red LED.

Les noir ne sont pas ir juste récepteurs