I am very new to electric engineering, so bear with me ;) Before building the circuit IRL, I wanted to try to build a simple 555 timer with a simulator following Ben eater's tutorial on it. Here are the schematics of the circuit...


If you want to see the tinkercad project... Now, even though I seem to have copied the exact same circuit as shown in the video (or at last so I think) - the first seconds of YT video - the 2uf capacitor doesn't seem to discharge trough Pin 7 when I simulate the circuit. What could be the problem here? I am 100% sure I am missing something very obvious but I have tried, and tried and tried to no avail. So I hope you guys could explain this to me :)

Thanks in advance!

  • \$\begingroup\$ Why do you have a wire joining pin-8 to pin-7? \$\endgroup\$
    – brhans
    Sep 24, 2019 at 20:21
  • \$\begingroup\$ How do you know the capacitor doesnt discharge? If the LED is not blinking, the cause may be the LED is connected incorrectly (swap its pins) \$\endgroup\$
    – Huisman
    Sep 24, 2019 at 20:22
  • 1
    \$\begingroup\$ What you've posted is a wiring diagram for a breadboard whereas we like to work with a schematic which is a diagram showing device symbols and, for integrated circuits such as your 555, the pin numbers and functions. That way we can see the scheme of the circuit. With such a simple circuit someone will be able to help you out. \$\endgroup\$
    – Transistor
    Sep 24, 2019 at 20:22
  • \$\begingroup\$ Sorry, without a schematic this wiring diagram is unreadable. Here is an example of a question with a good schematic: electronics.stackexchange.com/questions/413326/… \$\endgroup\$
    – MarkU
    Sep 24, 2019 at 20:22
  • \$\begingroup\$ Like @brhans suggests, it looks like pin 7 & 8 are connected together, but zooming in, the resistor is not stuck into the breadboard. Please improve the image so it becomes clear whether those pins are connected or not. \$\endgroup\$
    – Huisman
    Sep 24, 2019 at 20:24

1 Answer 1


It looks like you have your LED pins shorted together. The way a breadboard works is every pin in that line is connected. You need to put the long LED leg in the line with the wire to pin 3 and the short leg on a new line with the resistor to ground

  • \$\begingroup\$ I am sooo dumb! Thank you sooo much! You're a life saver \$\endgroup\$
    – FireGreeks
    Sep 24, 2019 at 20:34

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