Clap the light up!! A bracelet that lights up when you clap.

Step 1: Components Needed

Mic (I took it from one of non working earphones)
Potentiometer 10K
Resistance 1k
Colored LEDS – 8
Transparent plastic pipe. (Diameter approx 1 cm)
NPN transistors – 2
3v lithium cell
Battery cap

Few wires, soldering iron, and a small piece of GPB and there you go!

Step 2: Basic Circuit & Working

Working :

We will use two transistors in cascade to provide amplification of current. Using two transistors will be enough to light up 7-8 leds using just 3v supply.

According to our circuit, the LEDs will glow only when Q2 turns ON, thus providing a ground path to LEDS. Q2 will turn on when Q1 does not conduct. So, we have to set the potentiometer in such a way that when you clap, only at that time the Q1 goes off. This value usually comes in between 4-4.5 k.

Note: Be careful about checking out positive and negative terminals of mic before soldering. Otherwise you may not get the output.

Step 3: Let’s Get Started:

Mount the above circuit on a small piece of GPB. Since we are making a wearable, we will try our best to adjust it all in the smallest size possible. (Image:1)

Cut out the unused portion of the board.

Next, solder the MIC and the battery cap.

And then connect LEDs in parallel.(Image:2)

After connecting it to the circuit, set the potentiometer.

Done?

Place it inside the tube.(Image:3)

We have covered the circuit with a thread. A hole is made in the pipe and ribbon has been taken out from it. A similar hole on the other end, and there you go!!