Have you ever used EL wire, or felt that it'd be nice to have a wire that lights up, instead of expensive LED strings? How about some that pulse with music? That's what this is for, the EL wire color organ. EL wire is composed of three wires. One big center wire surrounded by a phosporous coating. Two smaller wires are wrapped around it, and connected at the end of the wire. One end is left open, the other connected to the power supply. When about 120VAC at a few kHz is run through it, the phosphorous glows. This is a problem for traditional color organs, as they use either low voltage DC for LEDs, or low frequency AC for incandescent lights. This project accomplishes the music reaction, high frequency, and high voltage issues with a small device. I used it for a tron-style holloween costume that reacts to music.
Step 1: Materials
Most of the parts for this are avaliable from Radioshack.
you will need:
2 x 2n3904 transistors
2 x 2n3906 transistors
2 x 555 timer ICs
1 x 2n339 quad comparator ICs
2 x 10K resistors
3 x 470 ohm resistors
1 x 1K ohm resistors
2 x 150K-500K potentiometers
1 x 1uf capacitor
2 x 0.22uf capacitors
1 x 0.1uf capacitor
1 x 100uf capacitor
2 x transformer 120V primary, 5V-12V secondary (any value between 5V and 12V will work, 5V will be brightest, 12V will be dimmest.)
1 x 9V battery (rechargable or not), and battery clip
1 x male 3.5mm audio jack
1 x female 3.5mm audio jack
1 x box
Everything here is avaliable from radioshack. It should be about $20 total.
Step 2: The EL Wire
You will also need EL wire, or another electroluminescent thing. Lightnwire.com has a good selection of size, length, brightness, color, and even some connectors and such. Go to http://lightnwire.com/raw.html
for the wire itself. Sparkfun.com also has a good color selection, though less options (only 3M, standard brightness). However, they have EL tape and pannels, which are flat, but still flexible and driven the same way.
edit: I just noticed that Radioshack also carries a similar selection to sparkfun. Now this can all be bought at once. Any of them will work. https://www.sparkfun.com/search/results?term=EL+&what=products
Note that lightpipe (the bottom few results) are NOT EL wire. They are more like fiber optic cable, and WILL NOT WORK. Most other lightwire vendors will work too.
If you wire already has connectors, then you will need the complementary connectors. Lightnwire EL wire comes with connectors already soldered on, and they sell connectors at the bottom of the page. If it does not have a connector, follow ladyada and Becky Sterns's tutorial on how to solder on a connector (for a TRON bag project) here: http://www.youtube.com/watch?v=PNvBM9JSeN0&playnext=1&list=PLE0E840B89D097604&feature=results_video
I am not affiliated with any manufacturer of anything.
Step 3: The Circuit
Now to building! The first picture is the schematic. The transformers should be reversed, so the normal "output" (secondary) is the primary (connected to the 2n3904s), and the normal input (120V, primary) is the secondary (connected to the EL wire). The side connected to the circuit will almost always have a lower resistance than the side connected to the EL wire. In the circuit, the EL wire is depicted as a capacitor. This is because it is. EL wire lights up only when the charge changes, and stores a tiny ammount of that charge for a tiny ammount of time. It glows as long as it holds a charge, which is why high-frequency AC is needed.
Note: make sure to check the pinout of the LM339, as I forgot to label pins. Also, the potentiometers are connected between the + input on each comparator, + rail (+9V). In case you are unfamiliar, the arrow pointing up is +9V, pointing down and filled in is 0V, and the three lines above each other are NOT 0V! That is the - audio input, and if connected to audio - will short the audio input. It is only connected between audio -, and the - input on the 2 comparators. Connect the - parts of the male and female 3.5mm jacks, but connect one channel from the male to the circuit, and the other side to both the left and right channels of the female jack. This is to avoid interference caused by the circuit.
Step 4: Testin'
To test the circuit, disconnect one lead of each transformer, and connect an LED with a 470 ohm resistor in its place. Then connect a 9V battery, and audio input device, such as an ipod. You should see the LEDs blink in time with the music. Adjust the potentiometers until neither LED stays on for more than one second at a time, or you may damage one of the transistors.
Once you have tuned it, then reconnect the transformers, making sure the output leads are not shorted. If it doesn't fry, then connect your lightwire. If all is well, it should light up. If not, check your wiring, and your transformers.
Safety notices: dont test transformers by plugging them in with the circuit attached. That will fry everything.
NEVER touch the output leads, they WILL shock you if they're working. They shouldn't have enough current to kill you, but you REALLY don't want to take the chance.
Step 5: Fire It Up
Put it in a box of some kind to make it sturdier, and then play some sick beats to jam out to. (I'm groovy man...). Maybe put the lightwire into a costume for holloween, (think TRON, or maybe dubstep?). I used this twice as my halloween costume, this year, however, I put it with my room's sound system. Anyway, tell me in the comments what you will use it/used it for.