Holiday Season is coming. Christmas decorations are everywhere. One of the gadgets that can be found everywhere are led tea light candles that really flicker. They are cheap, clean and not as dangerous as real candles.
But how do they work?
I read somewhere that the flickering was obtained by a sound generating chip hidden inside. I tried and tried to find the original article back, but I did not succeed. So I went shopping and made this instructable. This is not my invention and all credits should go to the person who first couldn't control his curiousity, just like me...
Important: I am not responsable if your experiments go wrong and you ruin your equipment, your Christmas or both. So be careful...
Step 1: Gather Materials
What you'll need is:
1) battery operated led tea light (less than 1 euro)
2) either one of following items:
- (computer) speaker
- mp3 player headphones
- audio cable
3) optional: little pieces of metal wire or a soldering iron in order to make the connections
Step 2: Open the Tea Light
In my case I had to do the following:
Remove the battery compartment cover.
With a small screwdriver open the bottom of the tea light.
Gently remove the electronics, it will be necessary to pull out the led from the silicone 'flame'. You'll see the led attached to a printed circuit board (PCB) and the PCB attached to the switch and the batteries.
Step 3: Connect to a Speaker
Connect the two leads from the led to the leads from a speaker. Be careful not to make a short circuit. If you want, you can remove the led and solder the wires directly to the PCB.
I don't think polarity is an issue in this case, so you can connect the two cables either way.
Now comes the moment of truth: switch on the tea light (at least the remains of it) and listen...
Step 4: Alternatives
1) Connect to mp3 player headphones
Connect the leads from the led to your headphones.
If you do not want to damage your headphones by cutting the cable, attach wires to the jack. Use the connections 3 (ground) and either connection 1 (right) or 2 (left). I found it more convenient to use connection 1 because of the little notch avoiding the cable to slip off.
2) Connect to your computer, amplifier etc.
Use an audio cable to hook up the tea light to a computer or amplifier. Connect to the line-in plug. I recorded the sound with my computer using audacity.
If you tried this instructable, led me know what sounds you found and enjoy the warmth of the tea lights or their music!