MAS.863 How to make (almost) anything.
Assignment October 13, 1999: Electronics and PCB
Stefan Marti and Kimiko Ryokai

Make something that blinks or makes sound.

This assignment is intended to make us play around with breadboards. And that's how ours looked like after playing:

The Metronome

First, we tried something very simple: a metronome, based on a 555 chip. The plan we got from a Radio Shack book. With a screwdriver, one can adjust the frequency of the clicks. That's it. The sound is made audible with a piezo loudspeaker. (Actually, the very first thing we did was a circuit that tests a 555 chip, but that was not doing a lot beside blinking if the chip is ok.)

And that's how it sounds: Metronome

The Sound Effect Generator

Then, we really wanted to do something more "expressive." We found a schematic for a simple sound FX generator in a similar Radio Shack booklet: "Enginer's Notebook: Integrated Circuit Apllications, 1980" (pretty advanced, synthesizers at this time...) It is based on a 556 chip. The three adjustable resistors influence the volume as well as the frequencies of the two built in timers.

Here's the schematic:

And that's the breadboard. It actually looks not much more complicated than the metronome, but the complexity is much higher due to the two 555 chips in the 556:

And that's how it sounds: Sound FX generator (To me personally, this sounds VERY much like a small R/C airplane... or the very cheap sound FX of VERY early video games! Viva Commodere 64! :-)