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led flasher circuit problem

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New Member
Ok so i found this led flasher circuit online ---> Simple LED flasher circuits

And i built it in eagle cad --->

But the thing is when I built the circuit all it does is light up the two leds and not flash them. Can some one help me with this circuit? I think their is a short circuit between the two transistors and the capacitor shown in the diagram but i figured thats their on purpose


Well-Known Member
Most Helpful Member
You show the pcb layout.
Post the schematic with part numbers instead.


New Member
Well the parts are just two 2n3904 transistors
2x 10uf 16v caps
2x leds
2x 330 ohm resistor "the ones on the left and right"
2x 100k ohm resistor "the two middle ones"

and it does not use any micro chips


Well-Known Member
It will not work.
It looks that both Q basis are connected together.


Good I'm glad it works.

Just a suggestion: you can get rid of the wire link by routing across the resistors.

I always try to avoid bridges because it saves soldering.:D
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