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I'm an electronics noob. I've been working through the book Make Electronics.

Experiment 16 is a 555 circuit. I'm trying to simulate it to see the pulses. However, my simulations all wind up steady state (DC output; no pulses from the 555 output).

The example 555 circuit at shows a nice sequence of output pulses. I'm trying to get that kind of result.

My circuit:

Screenshots from the book's PDF:

Schematic:

Components:

Why can't I see pulses on my output? Is my circuit set up correctly? Am I configuring the simulation settings correctly?

Many thanks.

@linuxlizard,

Welcome to CL.

Your circuit has several errors in the wiring.

Don't worry though: you can't blow up a simulation.

Your errors are failry typical newbie mistakes: we've all made them and they're easy enough to fix.

The best way to fix it is to have a careful read through this:

http://en.wikipedia.org/wiki/555_timer_IC

with particular attention to the Astable section.

Also take a bit of time to compare your circuit with:

https://www.circuitlab.com/circuit/e38756/555-timer-as-astable-multivibrator-oscillator/

https://www.circuitlab.com/circuit/kg6m5q/555-timer-astable/

to see how to make a working simulation of a 555 astable (which is what your circuit is trying to be).

It should all click into place then.

Good luck.

:)

Thanks! Looking at the simpler 555 circuits has helped me better understand the 555.

I did build the circuit from the book and it didn't blow up. Didn't work as expected (required a fairly large C4 to get the LED to light) but eventually did work.

So much to learn... O_o