Found in an English publication from the 1980s, this circuit can be built with equivalent transistors such as the BC549. The signal must be applied to an external amplifier.
This circuit was found in an old GE SCR manual. The SCR must be in accordance with the relay and...
Found in an Electronics Now from the 90s this mixer has several inputs. The integrated circuit can...
In the figure we have a piezoelectric transducer drive circuit that can be used in conjunction with the...