Today I am going to make a circuit of LED Flasher using BD139 Transistor.
Let's get started,
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.
Step 1: Take All Components As Shown Below
Step 2: Circuit Diagram
This is the circuit diagram of this project.
Connect all components according to this circuit diagram.
Step 3: Connect 4.7uf Capacitor
Solder +ve pin of capacitor to Base pin of transistor
and solder -ve pin of capacitor to emmiter pin of the transistor as solder in the picture.
Step 4: Connect 2200uf Capacitor
Next we have to solder +ve pin of 2200uf capacitor to emmiter pin of the transistor as you can see in the picture.
Step 5: Connect LED to the Circuit
Next we have to solder +ve leg of LED to Collector pin of transistor and
solder -ve pin of LED to -ve of 2200uf capacitor as you can see in the picture.
Step 6: Connect 1K Resistor
Next solder 1K resistor to -ve pin of 2200uf capacitor/-ve leg of LED as solder in the picture.
Step 7: Connect Power Supply Wire
Our circuit is completed.
So Now we have to connect input power supply wire to the circuit.
Connect +ve clip to Emmiter pin of Transistor and
Connect -ve clip to 1K resistor as you can see in the picture.
NOTE : We have to give 12V DC Input Power supply to this circuit.
Now LED will be flashing.