Using an integrated circuit that was available at the time, this circuit produces animal sounds such as mooing, rooster crowing, etc. The circuit is from a March 1997 Electronics Now magazine.
The circuit shown is from an old European publication. In it we have the way to activate a relay...
We found this circuit in a European publication from the 1990s. Transistors are still common types...
This circuit was found in an American documentation and can be added to common amplifiers of any...