The two integrated circuits used in this configuration can still be found. The frequencies of the effects are determined by the capacitors, which may have their values changed.
This circuit was obtained in a documentation of the 80s, using operational of the time. The...
In the figure we have a third fast adder that we found in an 80's Electronic Engineering. The circuit can...
We found this simple music box circuit that can also be used in a musical bell in a 1991...