This circuit was obtained from an American documentation from the 90's. The components can be changed, and a power step can be added for greater sound volume.
We found this circuit in the July 1994 issue of Electronics Now magazine. The circuit can use...
The transistors in this 80's documentation project may be BC548, the most modern equivalents of...
This circuit was found in an Electronic World of 1968. The circuit uses power transistors of the...