555 timer trouble

[Ohmeister25]

Hi i'm new to this forum and i have limited knowledge on electronics but i am having a particular trouble with a 555 timer ic.

I'm trying to make a simple LED pulser circuit (which could make a relay turn on and off) but when i turn it on the LED is constantly on but there is no overheating from the ic itself (which is odd). I'm not sure if my resistor values are or capacitor values are wrong. I have a 100uf electrolytic and a 0.1uf ceramic capacitors plus a 1k and 10k resistors with a 1M ohm potentiometer.I am using 6v to power this circuit. Please help.

Thanks
Ohmeister25

[nicholasdark]

Hi Ohmeister,
Are you able to post a schematic of it, or link to a dropbox link etc. with the schematic in?

Even if it's just hand drawn on an envelope it would be a good start

Nick

[Ohmeister25]

I don't exactly remember the shecmatic but it is similar to this one ( the potentiometer isn't needed i remembered).
Thanks for the response.
Ohmeister25

[Pauldf]

If it is wired as above it ought to work, a small resistor around 200 ohms is required in series with the LED in a 6v supply. For the supply are you using a battery or some sort of PSU? Astable 555 circuits don't like unsmoothed PSUs.

When you come to install the relay it is probably a good idea to use some sort of transistor such as a BFY51 to drive it.

[Ohmeister25]

I'm going to use a 6V battery pack to power this and i will consider getting a relay and transistor as you suggest to maybe have a smoothed PSU. If i was going to get a Smoothed PSU where should i look? Also what is the difference between smoothed and unsmoothed?
Thanks
Ohmeister25

[Pauldf]

A smoothed power supply has capacitors in it to ensure the output is a constant voltage, similar to the supply a battery will deliver.
As our mains is AC deriving DC from it without any smoothing will look like a series of hump back bridges, the voltage going from +v to 0, one hundred times per second = too fast for the eye to see but electronics don't like it.