555 Timer Astable Mode

Alright, first of all: Ground MUST be grounded. Second of all. After lowering adding a ground connection to the 10uF cap and to ground. You would get voltages too low to trigger the 555. So lower R1 to 14k and R2 to 10k for a minimal voltage to trigger the 555.

Also you should have a 10nF cap grounded from CTRL(pin 5) to ground.

Heres a link to what I did. http://everycircuit.com/circuit/6730933167456256

After analysing your voltage divider, it gives you 5v BUT with an impedance of 50uA which gives a power of 0.003 Watts

Voltage dividers as such can drift when supplying the pulses, a zener reference is recommended, http://everycircuit.com/circuit/5556664668520448

sshsslfun I know there was supposed to be a ground. I deleted it when I saw that it changed the voltage out of the voltage divider. I just want to know why the voltage drops so dramatically when you add a circuit to it. It doesn't make any sense. I used the formula for the voltage divider and it worked but as soon as I used the output voltage, it drops significantly.

Additionally, if I bring up the voltage to 100v it works. Highly unrealistic. I think there is something wrong with this simulator. I am going to try this on a bread board and I'll post the results. I do like the zener diode idea but I don't have any of those at the moment.

What BillyT said is a great and cheap way to do this. Ground has to be present or the circuit will not turn on. Ground indicates that the connecting node leads to the negative terminal of the voltage source. Try lighting an Led without a connection from the negative terminal to the VCC's negative terminal. It wont light up. Thats why you need a ground. In your case of removing ground, the 555 wasn't on and made the illusion of having a higher voltage and amperage.

I do know about the ground. That is obvious but why would a 555 timer drop my 5v source to only 69.2mV?

Hopefully this might help: http://everycircuit.com/circuit/5574601794125824

Ok lets do some math. You have to know how much power is going into the IC. To find P(Power) you must do V x I(impendance). In this case I = 0.00005 and V = 5. 5 times 0.00005 gives you 0.00025 Watts of power. So P = 0.00025. So now, you are getting 0.253 mV and 0.0000839 amps. So whats the power now? It is 0.0000225929 Watts. Why isn't the power the same as it was before? That's a bit tricky and more for another day. To finish this, just switch both resistors to 1k to get a 5V input with the recommended Amperage on the datasheet.(6 mA)

I talked to an engineer from my work and he says there is internal resistance inside the 555 timer and it would then make it parallel to my voltage divider making it smaller or some variation of that. He says the Zener Diode method would be the best bet for this circuit but there are other ways of doing it.

M_C there are other ways of doing it, but remember the 555 requires a certain amount of current to work, if the supply voltage has to come through too much resistance, it won't get that current the zener circuit, as shown ensues that it does. The desired zener current for EC is 13.6 mA.

I tried the original circuit on a bread board and it did not work at all. I don't have a meter yet because mine broke. The 555 timer circuit works but to power the LED, it was better when I turned up my power supply to 9v.

@Master_Crafter ... Whichever method you choose, be sure to keep input resistors low value enough to allow plenty current to pass for the setup to work...That is the main point that is being stressed here by the guys above. Your original setup divider resistors could not work even if the ratio was correct, due to the low current availability with those high value resistors. Likewise, your 1k resistor for the zener will not allow enough current to pass...see how the lower value of the BillyT resistor allows enough current, as he described. Your op-amp in this latest alteration here would be better set to default gain and a + max output of whatever your board is going to input to it ...eg 12v or 5v according to where you connect it. You also need to highlight any part and look at the time setting on the EC scope...it needs to be set at 1s for the LED flash rate to be meaningful.

Also when you bread board a circuit using a battery or bench power supply, the negative power supply lead is considered the earth.