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Tutorials & Projects

The Three Fives Kit: A Discrete 555 Timer /EMS 555

£34.50 £28.75 ex. VAT
9 in stock

Re-create one of the most classic, popular, and all-around useful chips of all time!

The "Three Fives" Discrete 555 Timer kit from Evil Mad Scientist Laboratories is a faithful and functional transistor-scale replica of the classic NE555 timer integrated circuit, one of the most classic, popular, and all-around useful chips of all time.

Designed by Eric Schlaepfer, in collaboration with Evil Mad Scientist Laboratories, to resemble an (overgrown) integrated circuit, based around an extra-thick matte-finish printed circuit board. It comes complete with a beautiful aluminum display stand that gives the circuit board eight legs in the shape of DIP-packaged integrated circuit pins.

The Three Fives circuit is a direct implementation of the "equivalent circuit" from the NE555 datasheet, built up using resistors and individual 2N3904 and 2N3906 transistors.

It comes with terminal posts and solder points so that you can actually connect to it and build up classic 555 timer and oscillator circuits. Using those terminal posts and solder points, you can hook up with with bare wires, lugs, alligator clips, and/or solder joints-- however you see fit.

And unlike the chip version, you can even hook up probes to monitor what goes on inside the circuit.

While the Three Fives kit will work without modification in the majority of example circuits, some performance characteristics are different than those of 555 integrated circuits; please refer to the Absolute Maximum Ratings and Electrical Characteristics in the datasheet for additional details.

Downloads and additional resources

  • Additional specifications are given in the kit's datasheet(2.7 MB PDF file).
  • Kit assembly instructions (1.4 MB PDF file).Printed instructions are included with the kit.
  • Evil Mad Scientist have written a detailed educational supplement for this kit, which goes into detail about how the circuit works: "Principles of Operation" (1.1 MB PDF)
  • The central documentation page for the kit is found here on the documentation wiki.