Traffic Light Project

Hii friend,

Today I am going to make a circuit of traffic light.This circuit I will make using BC547 Transistors.

Let's get started,

Components required -

(1.) Transistor - BC547 x3

(2.) Resistor - 1K x3

(3.) Resistor - 100K x2

(4.) Resistor - 33K x1

(5.) Red LED - 3V x2

(6.) Yellow LED - 3V x2

(7.) Green LED - 3V x2

(8.) Capacitor - 25V 470uf x2

(9.) Capacitor - 25V 100uf x1

(10.) Battery - 9V x1

(11.) Battery clipper x1

As pins are folded in the picture like that we have to fold.

Solder +ve legs of Both Red LED to Collector pin of a Transistor.

Solder +ve legs of Both Green LEDs to Collector pin of 2nd Transistor.

Solder +ve legs of Both Yellow LED to Collector pin of 3rd Transistor as solder in the picture.

Next we have to connect emmiter pins of all transistors and -ve legs of all LEDs (Red, Green and Yellow) to each other as you can see in the picture.

Next Connect 1K resistors to the Collector pins of all transistors as solder in the picture.

Next solder 100K resistors to the Base pin of Green and Red LED Transistor as you can see in the picture.

Solder 33K resistor to the Base pin of Yellow LED Transistor as solder in picture.

Next we have to solder Out wires of all Resistors as you can see in the picture.

Next solder +ve pin of 100uf capacitor to Base pin of Yellow LED Transistor and Solder -ve pin to Collector pin of Red LED Transistor as you can see in the picture.

[Capacitor 1] - Next connect +ve pin of 470uf capacitor to Base pin of Green LED and solder -ve pin to Collector pin of Yellow LED as solder in the picture.

[Capacitor 2] - Solder -ve pin of 2nd 470uf capacitor to Collector pin of Green LED Transistor.

Solder +ve pin of 2nd 470uf Capacitor to Base Pin of Red LED Transistor using a wire as you can see in the picture.

Solder +ve wire of battery clipper to Out wires of all resistors and -ve wire to common emmiter pins of transistors and -ve legs of LEDs as connected in the picture.

Now circuit is completed so connect Battery to battery clipper and see the Traffic Light how it is glowing.

NOTE : We can Increase/Decrease the timing of Red,Green and Yellow wire glowing by changing the values of capacitors.

Glowing of Traffic light I tried to show in the above pictures.

Thank you