How to Make VU Meter Using Transistor

Hii friend,

Today I am going to make a VU Meter circuit using only one transistor.In this VU Meter I will use 2N2222A Transistor.This VU Meter is not good as compare to 3915 IC VU Meter.

Let's get stated,

Step 1: Take All Components As Shown Below

Components required -

(1.) Transistor - 2N2222A x1

(2.) LED - 3V x6 (Any color)

(3.) Resistor - 1K x6

(4.) aux cable x1

(5.) Zero PCB

(6.) Battery - 9V

(7.) Battery clipper

Step 2: Transistor - 2N2222A

This is the pinout of this transistor.

Pin-1 is Emmiter,

Pin-2 is Base and

Pin-3 of this transistor is Collector.

Step 3: Connect All LEDs

Put all LEDs on the Zero PCB and Solder it's legs in series.

Step 4: Connect LEDs in Series

Solder +ve leg of one LED to -ve leg of another LED as solder in the picture.

Step 5: Connect 1K Resistors

Next we have to connect 1K resistors to +ve legs of all LEDs as you can see in the picture.

Step 6: Connect Other Side of Resistors

Solder all out wires of 1K Resistors to each other. {Connect all pins of other side of 1K Resistors} as you can see in the picture.

Step 7: Put Transistor

Next we have to connect the transistor to the PCB.

Connect Collector pin of transistor to the -ve legs of all LEDs as solder in the picture.

Step 8: Connect Aux Cable Wire

Next we have to connect aux cable wire to the circuit.

Solder +ve wire {Left/Right} of aux cable to the Base pin of Transistor and

Connect -ve wire {GND} of aux cable to emmiter pin of the transistor.

Step 9: Connect Battery Clipper Wire

Now we have to connect battery clipper to the circuit.

Connect +ve wire of battery clipper to Out {Other side of 1K Resistor} Side of the 1K Resistor and

-ve wire of battery clipper to Emmiter pin of the transistor as you can see in the picture.

Step 10: How to Use VU Meter

VU Meter Shows the audio level of the music.

Connect 9V Battery to the Battery clipper and Plug-in aux cable to the phone/laptop/tab..... and play songs.

Now As music will play like that LEDs will glow.

This type we can make Only One Transistor to VU Meter circuit.

Thank you