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555 Timer Tester

555 Timer Tester


This is a useful little circuit. When I first worked with 555s they were dying constantly, which becomes annoying quickly. This nifty little circuit will quickly tell you whether or not a 555 is functioning. Great for troubleshooting 555 related circuits. The LED will flash if the 555 is functional. If anything else happens the 555 has released it's magic smoke.

555 Timer Tester Schematic

The frequency is set at about 1 Hz. By using a 555 timer calculator it can be adjusted easily. The maximum frequency is around 300 - 500kHz.

Timer Tester view from aboveTimer Tester view of bottom

As you see I’ve built my tester on top of a button cell battery holder. This reduces size and leaves everything in a nice easy access package.



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Disclaimer: I do not take responsibility for any injury, death, hurt ego, or other forms of personal damage which may result from recreating these experiments. Projects are merely presented as a source of inspiration, and should only be conducted by responsible individuals, or under the supervision of responsible individuals. It is your own life, so proceed at your own risk! All projects are for noncommercial use only.


Creative Commons License This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported License.


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