What is this component? I recieved it for free from China but I can’t identify it.

Thread Starter

martonbaksa

Joined Apr 16, 2018
8
Hi all,
I recieved a package from China and inside the box there was “a free gift of 250grams of random electronics”. I recognized most of the things inside as they were resistors, capacitors etc, but this one unmarked component stumped me. It didn’t read any capacitance, the resistance fluctuated from 3m ohms to 111k ohms. In general this left me stumped. Here’s a photo of the component:
https://ibb.co/ki0zzT

Thanks for your help,
martonbaksa

Ps. The scale is in cm. if that helps.
 

bertus

Joined Apr 5, 2008
22,270
Hello,

I cropped the parts from the huge picture:

Marton Unknown Component.png

I think they could be IR leds, like the ones used for remote control.

Bertus
 

bertus

Joined Apr 5, 2008
22,270
Hello,

It depends on the current and voltage range of the diode test of your meter.
An IR led should have a forward voltage of about 1.1-1.4 volts.

Bertus
 

Thread Starter

martonbaksa

Joined Apr 16, 2018
8
Hello,

It depends on the current and voltage range of the diode test of your meter.
An IR led should have a forward voltage of about 1.1-1.4 volts.

Bertus
Ok. Thanks for the help. I have no way to test a diode with that forward voltage as I have no receiver for the led. When I have such a means of testing I will confirm what these components actually are. Thanks everyone for your help.
Sincerely,
martonbaksa
 

AlbertHall

Joined Jun 4, 2014
12,345
If you have a 9V battery and a 1kΩ resistor then connect them in series with a 'mystery' device and measure the voltage across the device. Try this with the device both ways round. If you get 9V one way and 1.5V to 4V the other way then it is likely they IR LEDs or just possibly phototransistors.
 

MrChips

Joined Oct 2, 2009
30,720
If you have a 9V battery and a 1kΩ resistor then connect them in series with a 'mystery' device and measure the voltage across the device. Try this with the device both ways round. If you get 9V one way and 1.5V to 4V the other way then it is likely they IR LEDs or just possibly phototransistors.
... and view the object with a digital camera. If it is IR emitter it will be visible with a digital camera.
 

Thread Starter

martonbaksa

Joined Apr 16, 2018
8
... and view the object with a digital camera. If it is IR emitter it will be visible with a digital camera.
Oh yeah. I forgot about the fact that digital cameras can see the IR Spectrum with a digital camera. I’m going to get around to this either later today or tomorrow and see the results. Thanks all for your help.
martonbaksa
 
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