How to Make LED Flasher Circuit Using BD139 Transistor ,How to make led flasher,  how to make led flasher circuit


Hello friend,

Today I am going to make a circuit of LED Flasher  by using BD139 Transistor.

Let's get started,

Stept : Take All Components As Shown in Below

Components required-

  1. Transistor-BD139x1
  2. Capacitor-16v200ufx1
  3. Capacitor-50v4.7ufx1
  4. Resistor-1Kx1
  5. Led - 3vx1
  6. Power supply- 12v Dc

Step 2: Circuit Diagram


  • This is a circuit diagram of the project
  • Connect all these components according to the circuit diagram

Step 3: Connect 4.7uf Capacitor


  • Solder +ve pin of capacitor to the Base pin of transistor and then solder -ve pin of capacitor to the  emmiter pin of the transistor as solder in the picture below.


Step 4: Connect 2200uf Capacitor

  • Next we have to solder +ve pin of 2200uf capacitor to  the emmiter pin of the transistor as you can see in the picture below.

Step 5: Connect LED to the Circuit


Then now will   solder +ve leg of LED to the  Collector pin of the  transistor and

solder -ve pin of LED to -ve of the  2200uf capacitor as you can see in the picture below. 

Step 6: Connect 1K Resistor


  • Now  will the solder 1K resistor to -ve pin of 2200uf capacitor/-ve leg of LED as solder in the picture below.

Step 7: Connect Power Supply Wire


  • Now will connect the supply 

Our circuit is completed.

So Now we have to connect input power supply wire to the circuit.

Connect postive clip to the  Emmiter pin of Transistor and

Connect negative clip to the  1K resistor as you can see in the picture below 

NOTE : We have to give 12V DC Input Power supply to this circuit.

Now LED will be flashing.

Thank you us .

https://youtu.be/zmJlA9_8wmQ