Introduction: Oh No Another Knight Rider
Yes I do know that there is lot's of instructables on this circuit, and that is easy to program one on lets say arduino then to build one from scrap using analog electronics.
I made this last night so I wanted to share it with you.The circuit is based on NE555 oscillation circuit that feeds IC 4017, the output pin 3 on the NE555 is connected to clock pin (14) on the 4017.
The oscillation circuit creates oscillation, the frequencies of the oscillation depends on the resistors and capacitors that are in the circuit with NE555:
f=1,44/(R1+2R2)*C
4017 uses this waves to activate outputs from 0-9.The speed of LED-s on/of depends on the wave that comes from NE555.
There are many circuits online but they are working on same principle, it is easy to program a PIC to make a same effect but I already did this using arduino and PIC16f877 but a wanted to see al the magic using analog electronic and reuse materials predicted to go in garbage.
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For this circuit I used:
-3x LED
-1x NE555
-1x capacitor 3.3uF or 2.2uF
-2x resistors 1k and 10 k
-1x IC 4017
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