Astable, in which the circuit is not stable in either state it continually switches from one state to the other. It does not require an input such as a clock pulse.  This circuit operates 3v Dc. When apply 9v Dc add in series Resistor 470E value =220 ohms or add 2 LED’s each sides if you want..

Astable animation Monostable, in which one of the states is stable, but the other state is unstable (transient). A trigger causes the circuit to enter the unstable state. After entering the unstable state, the circuit will return to the stable state after a set time. Such a circuit is useful for creating a timing period of fixed duration in response to some external event. This circuit is also known as a one shot. Bistable, in which the circuit is stable in either state. The circuit can be flipped from one state to the other by an external event or trigger.

The Astable Multivibrator circuit using 1 Red colour and Green LED, two NPN small transistor BC148 for switching.  The Supply voltage is +6V or if you want to supply a larger volt then add a required resistor series connected with  2 LED’s. I recommend to use +6V for best result. +3.7V you can use a battery of  mobile phone.  
 When Change the Transistor SL100 or 2N2222 the resistor value 10k=1k, 68k=5k, the capacitor value may be changed to your time (100 mfd to 220 mfd).

About the Author


Hello! My Dear Friends. I am Subramanian. I am writing posts on androiderode about Electronics testing and equipments.

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