# VU Meter Using 3915 IC

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Hii friend,

Today I am going to make a VU Meter Meter circuit that will show the level of audio in the LED.In this VU Meter I will use 10 LED.

Let's get started,

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## Step 1: Components Required

(1.) IC - 3915 x1

(2.) IC base - 18 Pin x1

(3.) Battery - 9V x1

(4.) Battery clipper x1

(5.) Resistor - 1K x1

(6.) Preset - 10K x1

(7.) LED - 3V x10 {Any color}

(8.) Zero PCB

## Step 2: Circuit Diagram

This is the circuit diagram of this VU Meter.

Connect all components according to this circuit diagram.

## Step 3: Connect LEDs

Firstly we have to Put all LEDs to the PCB as you want color of LEDs.

+ve legs of LEDs should be upper side and -ve legs should be in the downward side.

## Step 4: Put IC Base

Next we have to put IC Base to the PCB as you can see in the picture.

## Step 5: Solder Pins of IC Base and LEDs

Next solder +ve legs of all LEDs to each other and

Solder All Pins of IC Base and -ve legs as you can see in the picture.

## Step 6: Connect -ve Legs of LEDs

Next Connect -ve Legs of LEDs to the IC base as given in the circuit diagram.

Solder -ve leg of LED-1 to Pin-1 of the IC,

Solder -ve leg of LED-2 to Pin-18 of the IC,

Solder -ve leg of LED-3 to Pin-17 of the IC,

Solder -ve leg of LED-4 to Pin-16 of the IC,

Solder -ve leg of LED-5 to Pin-15 of the IC,

Solder -ve leg of LED-6 to Pin-14 of the IC,

Solder -ve leg of LED-7 to Pin-13 of the IC,

Solder -ve leg of LED-8 to Pin-12 of the IC,

Solder -ve leg of LED-9 to Pin-11 of the IC and

Solder -ve leg of LED-10 to Pin-10 of the IC as you can see in the picture.

## Step 8: Connect 1K Resistor

Next connect 1K Resistor to the circuit.

Solder 1K Resistor Between Pin-7 to Pin-8 of the IC as you can see in the picture.

## Step 10: Sort Pin-2 and Pin4

Solder Pin-2 to Pin-4 and with 10K Preset as given in the circuit diagram.

## Step 11: Short Pin-3 and Pin-9

Next short pin-3 and Pin-9 and solder a wire from Pin-9 to +ve of LEDs as solder in the picture.

## Step 12: Connect Battery Clipper Wire

Next solder battery clipper wire to the PCB.

Solder +ve wire of battery clipper to +ve Pin of LEDs/Pin-3,9 of IC and -ve wire to Pin-2 of the IC as given in the circuit diagram.

## Step 13: Connect Aux Cable Wires

Now we can give audio input using amplifier/aux cable... to this circuit.

{Here I an giving with the aux cable}

Solder +ve wire of aux cable to the Pin-5 of the IC and -ve wire to the Pin-2,4 of the IC as you can see in the circuit diagram.

## Step 14: How to Use This VU Meter

Connect Battery to the circuit and Plug-in aux cable to Mobile phone and play songs.

As audio level will be of the song like that LEDs will glow.

Thank you

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