LED Running circuit - Astable Multivibrator

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Astable Multivibrator is also called 'Free Running relaxation oscillator' and is commonly used to create square wave generation. As a hobby circuit, it is used as LED running circuit.  


Components Required

Light Emitting Diodes : 2 
Resistors: 470 - 2 and 47K - 2
Capacitor: 10µf  - 2
Battery: 9V
Transisitor: BC548 - 2

Figure shows circuit diagram of a Astable Multivibrator.
Astable Multivibrator with LED | LED Running circuit | Fancy LED circuit
Astable Multivibrator with LED | LED Running circuit | Fancy LED circuit
The Resistors used in the above circuit are very common in the market.  

Capacitor values are not mentioned in the above circuit because you can use any amount of capacitors (both should be same value). As capacitance changes, the delay between ON and OFF of LED's also be changed. Use capacitors of 10 µf  for standard delay.

The working principle behind the Astable Multivibrator is, turning ON and OFF of transistors, ie, when transistor Q1 is ON, the Q2 will be in OFF condition. The delay between ON and OFF of transistors are determined by the capacitors. 

Need any Assistance? Have any doubts/comments on the construction or working? Feel free to add it as comment below. 
Thanks for reading and sharing :)