Error in my 555 timer circuit?

Question

i have everything hooked up the led goes on but it doesnt flash any help?( it runs on a 9v battery )

http://i136.photobucket.com/albums/q187/v1p3r1337/timercircuit.jpg

Answer 1

Be nice to see the circuit and the values you used, but one resistor connected to pin 6 and 7 must be less than 1/2 than the one connected from Vcc to pin 7 to possibly trigger the output.

What type of circuit are you using?  Monostable, astable, what?

Ron

Answer 2

I think you may be working to the wrong circuit. What you want is an astable such as this..

<>http://www.doctronics.co.uk/555.htm#asta...

don't ignore the extra capacitors, they have a purpose. Decoupling and stabilization components are quite often required to make circuits work.

The resistor you have used is 22 Ohms which is way too low.

Make R1 = 1k Ohm. For a capacitor in mfd and R2 in MegOhms the frequency will be in seconds.

Answer 3

I see only 1 resistor.  Typically, there are two: one to charge the timing capacitor, one to discharge the timing capacitor.

the timing cap is usually between ground and pin 2.  Pin 2 is usually jumpered to pin 6, and one resistor goes from 6 to 7, the other from 7 to +Vcc.

8 & 4 are usually +Vcc.

1 should be grounded, and lastly, you'll need a current limiting resistor between pins 3 and the LED anode.  use 330 for 5 V supply, 1k for 12 V supply.  LED cathode goes to ground.

Sometimes, pin 5 is connected to ground through a small cap.

Answer 4

You may have a unidirectional capacitor installed in the wrong direction.  Try reversing it.