555 timer

[simo]

Main Question or Discussion Point

Can you tell me what is wrong with my timer. I want it to make a relay open and shut periodically. For some reason it's not working.

 

[berkeman]

Can you tell me what is wrong with my timer. I want it to make a relay open and shut periodically. For some reason it's not working.

You show your output directly shorted to ground. Is that correct, or a typo?

 

[simo]

You show your output directly shorted to ground. Is that correct, or a typo?

Nope, that's how I made it.

If I disconnect the output/diode junction from ground, would it sink the current?

 

[dlgoff]

If you do the calculation from the numbers you give, the sink current would be about 11ma, so the 555 should be able to sink that.