Instructables

Why wont this led flasher circuit work?

I recently made an led flasher circuit using a 555 timer on a breadboard. The instructable I used was this: http://www.instructables.com/id/How_to_use_555_timers/

When I made the whole thing on the breadboard, it worked. (I used a reed relay instead of a switch for the power, so i could use a magnet to turn it on and off and it worked). Then I took the circuit and transferred it to a circuit board. I made the first part, with the one led that just lights up, and when I tested it, it didnt work. I checked and made sure power went through all of the objects, and it did. The breadboard circuit I used a 5+ power supply, on the circuit board I used a battery holder (That holds 4 1.5 batteries) to get 6 volts. (I used 6 volts with the breadboard circuit, too) I used all the same pieces, tested the led and it worked, but it just doesnt work. Here is the circuit drawn on paint (As it is on the circuit board):

Picture of Why wont this led flasher circuit work?
wccolvin5 years ago
Forgive me if I am wrong,but I don't see a 555 Timer in the Circuit.There also is no Capacitor to Charge and Discharge to cause a flash.
travis7s5 years ago
You could skip the regulator if you want, just adjust the resistor appropriately.
101yummYYummy101 (author) 5 years ago
No, I only did the first half of it that the light turns on when power goes through, and turns off when power goes out. But Im trying to use a 9 volt battery now, gotta change resistor first.
frollard5 years ago
Weird - I can't reply to the 'best answer'... anyhoo - Circuit is good as Andy says - but, if I'm looking at this right, it wont...flash...:) is that intentional?
AndyGadget5 years ago
Your circuit wiring is fine, but the problem is that the regulator (I assume you're using a 7805) needs more than 8V at the input to get it working. This should run OK off a 9V battery.