This is the second version of my homemade oscillator synth box thingy. It uses a 555 chip like the last one and a 556 like in Forrest Mims III’s “sound synthesizer” AKA the Atari Punk Console.
Top right, there is a toggle switch to power up a repeating rhythmic pulse or a push button that only plays when its pressed down.
At the top are two flashing LED arms linked to two of the oscillators’ outputs. In the center is a photoresistor linked to the pitch control.
The knobs control the rate, pitch, and range.
The “keyboard” has four tunable buttons that can control either the pitch or the range.
On the right are two switches that exchange capacitor values jumping the pitch up or just changing the timbre depending on the other settings.
And below that are three switches that route the 555 back into various pins on the 556 for a variety of lively tonal effects reminiscent of the harp or a piano.
So there it is! Fun to play and look at. If I can find some decent enclosures, I may try to build some more of these.
Here are the two Schatz boxes in tandem:
