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LED Flasher


This LED flasher is based on 555 timer. One can use this flasher circuit either on bike/cycle or in police car!. The operating voltage of the circuit is 9v, but you can also use it at 6v. 

Two sets of six LEDs are used here, but you can extend it to 40 each set. Flash cycle is determine by the RC time constant. However by using the pot you can set the flash rate of your choice.

Transistor are used; to provide the additional current for leds and to switch the LEDs set at a time. Rest of the circuit is simple, no need to explain it; i guess. Now come to the circuit schematic.
Schematic:
LED Flasher
Components Required:
R1----------------------------4.7k ohm
R3, R4-----------------------220 ohm
R2 (VR1)---------------------150k or 220k pot
R5-R10-----------------------100 ohm
C1-----------------------------100nF Ceramic
C2-----------------------------1uF/25v Electrolyte
Q1-----------------------------BC547
Q2----------------------------BC557
D2-D7------------------------Blue LEDs
D8-D13-----------------------Red LEDs
U1------------------------------555 Timer


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