# Light 40 Leds With a Dead Battery!!!

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## Introduction: Light 40 Leds With a Dead Battery!!!

Hey there! this is my another new instructable on
HOW TO LIGHT 40 LEDS WITH A DEAD 'AA BATTERY'.

Please support me by liking it :-)

The working of the circuit is based on the legendry 'joule-thief' circuit.

### Teacher Notes

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## Step 1: Materials Needed

You need the following

Transistor 2n2222

Resistor 1 kilo ohms

A ferrite torroid (circular metal disc-like thing YOU CAN FIND THIS IN OLD CFL LAMPS)

Led's (i used 40 of them!!!)

wires

## Step 2: Start Winding the Torroid.

To begin with the coil remember that it is the most important thing in the circuit.

●STEP 1 - ( SEE THE IMAGES )Take your torroid and start winding it with a single round of copper coil or coated wire.

●STEP 2 - Twist the '2 ends' of the wire so that you don't get confused.

●STEP 3 - Again repeat the winding of the coil as in step 1

●STEP 4 - Twist the '2 ends' of the wire so that you don't get confused.

REMOVE THE THIN COATING OR ENAMEL FROM THE COIL BY BURNING ITS ENDS OR SIMPLY RUBBING THEM WITH A SANDPAPER.

## Step 4: Lets Begin With the Wiring.

Bread-board the circuit to get a basic idea of its working

## Step 5: Wiring Connections

CAREFULY WIRE THE CIRCUIT AS GIVEN

●STEP 1- Solder the base of the transistor to the 1 kilo-ohm resistor.

●STEP 2- Solder the other end of the resistor to any end of the the torroid

●STEP 3- ( AS IN THE CIRCUIT DIAGRAM ) Join the 2 different ends of the torroid together
and solder the possitive terminal of the dead battery to it.

●STEP 4- Solder the possitive terminal of the led to the collector of the transistor.

●STEP 5- Solder the negative terminal of the led to the emmiter of the transistor.

●STEP 6- Solder the left-out wire of the torroid coil to the emmiter of the transistor.

●STEP 7- Solder the negative terminal of the battery to the
collector of the transistor.

## Step 6: Now See the Circuit Play

THIS CIRCUIT CAN LIGHT 40 LEDS USING 0.3 VOLTS ONLY.

Each led used above requires 3 volts

40 × 3 = 120 volts!!!

But i am only supplying 0.3 volts to it.

THE CIRCUIT MAKES 0.3 VOLTS INPUT DO A JOB REQUIRING 120 VOLTS!!!

## Step 8: ALSO IT CAN POWER ALL YOUR HALLOWEEN STUFF TOO !!

MY NEXT INSTRUCTABLE WOULD BE ON LIFE HACKS OR A BLOODY PAINTING PROP.

STAY TUNED!!!

HAVE A NICE DAY

Participated in the
Circuits Contest 2016

Participated in the
LED Contest

## Recommendations

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## 5 Discussions

It's cool that you are learning about this stuff and sharing what you learn! A couple things to help you on your journey: It looks like you have all the LEDs connected in parallel, that means you still only need the voltage it would take to turn on one of them to turn on all of them, but the current will get split between them. I'm quite sure your battery hasn't been drained to .3 volts since that isn't enough to turn on the transistor. This circuit is known as a Joule thief and doesn't really work below .6-.7 volts input, although there is a version which uses a MOSFET which can go lower. Keep building stuff!

Thank you I'll keep this in mind next time

can light all 40 leds? i done by 1 led plzz reply ro me

you can give the multimeter reading for the voltage in battery

BUT A GOOD ONE!!!!!!!!!