This circuit that generates a special sound was found in a Popular Electronics from the 90s. The base is the 555 and the transistors admit equivalents, and a power stage can be added.
This circuit was found in the March 1980 issue of Radio Electronics magazine. It is based on the...
We found this circuit in a 2005 Linear Technology manual. The resistor is calculated for the...
Here we have a signal injector for the medium wave range, which uses only one transistor. This...